diff options
Diffstat (limited to 'vendor/num-rational')
-rw-r--r-- | vendor/num-rational/.cargo-checksum.json | 1 | ||||
-rw-r--r-- | vendor/num-rational/Cargo.toml | 79 | ||||
-rw-r--r-- | vendor/num-rational/LICENSE-APACHE | 201 | ||||
-rw-r--r-- | vendor/num-rational/LICENSE-MIT | 25 | ||||
-rw-r--r-- | vendor/num-rational/README.md | 51 | ||||
-rw-r--r-- | vendor/num-rational/RELEASES.md | 160 | ||||
-rw-r--r-- | vendor/num-rational/build.rs | 8 | ||||
-rw-r--r-- | vendor/num-rational/src/lib.rs | 3106 | ||||
-rw-r--r-- | vendor/num-rational/src/pow.rs | 173 |
9 files changed, 3804 insertions, 0 deletions
diff --git a/vendor/num-rational/.cargo-checksum.json b/vendor/num-rational/.cargo-checksum.json new file mode 100644 index 0000000..3e486ca --- /dev/null +++ b/vendor/num-rational/.cargo-checksum.json @@ -0,0 +1 @@ +{"files":{"Cargo.toml":"9951a0d2a04403a009b2b07953b430ece2b2ca44c44b1c5b2b566ba162cac951","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"6485b8ed310d3f0340bf1ad1f47645069ce4069dcc6bb46c7d5c6faf41de1fdb","README.md":"61154a19b71dd682b1955273e602e687d0cfc152afcfdf9fc9ee11beb083704a","RELEASES.md":"8e4d5cb5d36225b298f1412204d342858e6b7cc4bf4d39b53b48dd1be1c5083a","build.rs":"43a2d0ec88488d561f7b367d83f8cce81ad68bdfd352a3db9c881574a734c44f","src/lib.rs":"43762876ac4587ca6f553c029e69d3228f70c611fd7a1a8f0d4ea7859d9939e1","src/pow.rs":"c38cabc61e75e99425ee4fea7ac5b0712a648baa0635a2c40a6215edd43ae4a3"},"package":"0638a1c9d0a3c0914158145bc76cff373a75a627e6ecbfb71cbe6f453a5a19b0"}
\ No newline at end of file diff --git a/vendor/num-rational/Cargo.toml b/vendor/num-rational/Cargo.toml new file mode 100644 index 0000000..b2608a9 --- /dev/null +++ b/vendor/num-rational/Cargo.toml @@ -0,0 +1,79 @@ +# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO +# +# When uploading crates to the registry Cargo will automatically +# "normalize" Cargo.toml files for maximal compatibility +# with all versions of Cargo and also rewrite `path` dependencies +# to registry (e.g., crates.io) dependencies. +# +# If you are reading this file be aware that the original Cargo.toml +# will likely look very different (and much more reasonable). +# See Cargo.toml.orig for the original contents. + +[package] +edition = "2018" +name = "num-rational" +version = "0.4.1" +authors = ["The Rust Project Developers"] +exclude = [ + "/bors.toml", + "/ci/*", + "/.github/*", +] +description = "Rational numbers implementation for Rust" +homepage = "https://github.com/rust-num/num-rational" +documentation = "https://docs.rs/num-rational" +readme = "README.md" +keywords = [ + "mathematics", + "numerics", + "fractions", +] +categories = [ + "algorithms", + "data-structures", + "science", + "no-std", +] +license = "MIT OR Apache-2.0" +repository = "https://github.com/rust-num/num-rational" + +[package.metadata.docs.rs] +features = [ + "std", + "num-bigint-std", + "serde", +] + +[dependencies.num-bigint] +version = "0.4.0" +optional = true +default-features = false + +[dependencies.num-integer] +version = "0.1.42" +features = ["i128"] +default-features = false + +[dependencies.num-traits] +version = "0.2.11" +features = ["i128"] +default-features = false + +[dependencies.serde] +version = "1.0.0" +optional = true +default-features = false + +[build-dependencies.autocfg] +version = "1.0.0" + +[features] +default = [ + "num-bigint-std", + "std", +] +num-bigint-std = ["num-bigint/std"] +std = [ + "num-integer/std", + "num-traits/std", +] diff --git a/vendor/num-rational/LICENSE-APACHE b/vendor/num-rational/LICENSE-APACHE new file mode 100644 index 0000000..16fe87b --- /dev/null +++ b/vendor/num-rational/LICENSE-APACHE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. Definitions. + + "License" shall mean the terms and conditions for use, reproduction, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. For the purposes of this definition, + "control" means (i) the power, direct or indirect, to cause the + direction or management of such entity, whether by contract or + otherwise, or (ii) ownership of fifty percent (50%) or more of the + outstanding shares, or (iii) beneficial ownership of such entity. + + "You" (or "Your") shall mean an individual or Legal Entity + exercising permissions granted by this License. + + "Source" form shall mean the preferred form for making modifications, + including but not limited to software source code, documentation + source, and configuration files. + + "Object" form shall mean any form resulting from mechanical + transformation or translation of a Source form, including but + not limited to compiled object code, generated documentation, + and conversions to other media types. + + "Work" shall mean the work of authorship, whether in Source or + Object form, made available under the License, as indicated by a + copyright notice that is included in or attached to the work + (an example is provided in the Appendix below). + + "Derivative Works" shall mean any work, whether in Source or Object + form, that is based on (or derived from) the Work and for which the + editorial revisions, annotations, elaborations, or other modifications + represent, as a whole, an original work of authorship. For the purposes + of this License, Derivative Works shall not include works that remain + separable from, or merely link (or bind by name) to the interfaces of, + the Work and Derivative Works thereof. + + "Contribution" shall mean any work of authorship, including + the original version of the Work and any modifications or additions + to that Work or Derivative Works thereof, that is intentionally + submitted to Licensor for inclusion in the Work by the copyright owner + or by an individual or Legal Entity authorized to submit on behalf of + the copyright owner. For the purposes of this definition, "submitted" + means any form of electronic, verbal, or written communication sent + to the Licensor or its representatives, including but not limited to + communication on electronic mailing lists, source code control systems, + and issue tracking systems that are managed by, or on behalf of, the + Licensor for the purpose of discussing and improving the Work, but + excluding communication that is conspicuously marked or otherwise + designated in writing by the copyright owner as "Not a Contribution." + + "Contributor" shall mean Licensor and any individual or Legal Entity + on behalf of whom a Contribution has been received by Licensor and + subsequently incorporated within the Work. + +2. Grant of Copyright License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + copyright license to reproduce, prepare Derivative Works of, + publicly display, publicly perform, sublicense, and distribute the + Work and such Derivative Works in Source or Object form. + +3. Grant of Patent License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + (except as stated in this section) patent license to make, have made, + use, offer to sell, sell, import, and otherwise transfer the Work, + where such license applies only to those patent claims licensable + by such Contributor that are necessarily infringed by their + Contribution(s) alone or by combination of their Contribution(s) + with the Work to which such Contribution(s) was submitted. If You + institute patent litigation against any entity (including a + cross-claim or counterclaim in a lawsuit) alleging that the Work + or a Contribution incorporated within the Work constitutes direct + or contributory patent infringement, then any patent licenses + granted to You under this License for that Work shall terminate + as of the date such litigation is filed. + +4. Redistribution. You may reproduce and distribute copies of the + Work or Derivative Works thereof in any medium, with or without + modifications, and in Source or Object form, provided that You + meet the following conditions: + + (a) You must give any other recipients of the Work or + Derivative Works a copy of this License; and + + (b) You must cause any modified files to carry prominent notices + stating that You changed the files; and + + (c) You must retain, in the Source form of any Derivative Works + that You distribute, all copyright, patent, trademark, and + attribution notices from the Source form of the Work, + excluding those notices that do not pertain to any part of + the Derivative Works; and + + (d) If the Work includes a "NOTICE" text file as part of its + distribution, then any Derivative Works that You distribute must + include a readable copy of the attribution notices contained + within such NOTICE file, excluding those notices that do not + pertain to any part of the Derivative Works, in at least one + of the following places: within a NOTICE text file distributed + as part of the Derivative Works; within the Source form or + documentation, if provided along with the Derivative Works; or, + within a display generated by the Derivative Works, if and + wherever such third-party notices normally appear. The contents + of the NOTICE file are for informational purposes only and + do not modify the License. You may add Your own attribution + notices within Derivative Works that You distribute, alongside + or as an addendum to the NOTICE text from the Work, provided + that such additional attribution notices cannot be construed + as modifying the License. + + You may add Your own copyright statement to Your modifications and + may provide additional or different license terms and conditions + for use, reproduction, or distribution of Your modifications, or + for any such Derivative Works as a whole, provided Your use, + reproduction, and distribution of the Work otherwise complies with + the conditions stated in this License. + +5. Submission of Contributions. Unless You explicitly state otherwise, + any Contribution intentionally submitted for inclusion in the Work + by You to the Licensor shall be under the terms and conditions of + this License, without any additional terms or conditions. + Notwithstanding the above, nothing herein shall supersede or modify + the terms of any separate license agreement you may have executed + with Licensor regarding such Contributions. + +6. Trademarks. This License does not grant permission to use the trade + names, trademarks, service marks, or product names of the Licensor, + except as required for reasonable and customary use in describing the + origin of the Work and reproducing the content of the NOTICE file. + +7. Disclaimer of Warranty. Unless required by applicable law or + agreed to in writing, Licensor provides the Work (and each + Contributor provides its Contributions) on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or + implied, including, without limitation, any warranties or conditions + of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A + PARTICULAR PURPOSE. You are solely responsible for determining the + appropriateness of using or redistributing the Work and assume any + risks associated with Your exercise of permissions under this License. + +8. Limitation of Liability. In no event and under no legal theory, + whether in tort (including negligence), contract, or otherwise, + unless required by applicable law (such as deliberate and grossly + negligent acts) or agreed to in writing, shall any Contributor be + liable to You for damages, including any direct, indirect, special, + incidental, or consequential damages of any character arising as a + result of this License or out of the use or inability to use the + Work (including but not limited to damages for loss of goodwill, + work stoppage, computer failure or malfunction, or any and all + other commercial damages or losses), even if such Contributor + has been advised of the possibility of such damages. + +9. Accepting Warranty or Additional Liability. While redistributing + the Work or Derivative Works thereof, You may choose to offer, + and charge a fee for, acceptance of support, warranty, indemnity, + or other liability obligations and/or rights consistent with this + License. However, in accepting such obligations, You may act only + on Your own behalf and on Your sole responsibility, not on behalf + of any other Contributor, and only if You agree to indemnify, + defend, and hold each Contributor harmless for any liability + incurred by, or claims asserted against, such Contributor by reason + of your accepting any such warranty or additional liability. + +END OF TERMS AND CONDITIONS + +APPENDIX: How to apply the Apache License to your work. + + To apply the Apache License to your work, attach the following + boilerplate notice, with the fields enclosed by brackets "[]" + replaced with your own identifying information. (Don't include + the brackets!) The text should be enclosed in the appropriate + comment syntax for the file format. We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + +Copyright [yyyy] [name of copyright owner] + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. diff --git a/vendor/num-rational/LICENSE-MIT b/vendor/num-rational/LICENSE-MIT new file mode 100644 index 0000000..39d4bdb --- /dev/null +++ b/vendor/num-rational/LICENSE-MIT @@ -0,0 +1,25 @@ +Copyright (c) 2014 The Rust Project Developers + +Permission is hereby granted, free of charge, to any +person obtaining a copy of this software and associated +documentation files (the "Software"), to deal in the +Software without restriction, including without +limitation the rights to use, copy, modify, merge, +publish, distribute, sublicense, and/or sell copies of +the Software, and to permit persons to whom the Software +is furnished to do so, subject to the following +conditions: + +The above copyright notice and this permission notice +shall be included in all copies or substantial portions +of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF +ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED +TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A +PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/vendor/num-rational/README.md b/vendor/num-rational/README.md new file mode 100644 index 0000000..7fc445c --- /dev/null +++ b/vendor/num-rational/README.md @@ -0,0 +1,51 @@ +# num-rational + +[![crate](https://img.shields.io/crates/v/num-rational.svg)](https://crates.io/crates/num-rational) +[![documentation](https://docs.rs/num-rational/badge.svg)](https://docs.rs/num-rational) +[![minimum rustc 1.31](https://img.shields.io/badge/rustc-1.31+-red.svg)](https://rust-lang.github.io/rfcs/2495-min-rust-version.html) +[![build status](https://github.com/rust-num/num-rational/workflows/master/badge.svg)](https://github.com/rust-num/num-rational/actions) + +Generic `Rational` numbers (aka fractions) for Rust. + +## Usage + +Add this to your `Cargo.toml`: + +```toml +[dependencies] +num-rational = "0.4" +``` + +## Features + +This crate can be used without the standard library (`#![no_std]`) by disabling +the default `std` feature. Use this in `Cargo.toml`: + +```toml +[dependencies.num-rational] +version = "0.4" +default-features = false +``` + +## Releases + +Release notes are available in [RELEASES.md](RELEASES.md). + +## Compatibility + +The `num-rational` crate is tested for rustc 1.31 and greater. + +## License + +Licensed under either of + + * [Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0) + * [MIT license](http://opensource.org/licenses/MIT) + +at your option. + +### Contribution + +Unless you explicitly state otherwise, any contribution intentionally submitted +for inclusion in the work by you, as defined in the Apache-2.0 license, shall be +dual licensed as above, without any additional terms or conditions. diff --git a/vendor/num-rational/RELEASES.md b/vendor/num-rational/RELEASES.md new file mode 100644 index 0000000..9fa163c --- /dev/null +++ b/vendor/num-rational/RELEASES.md @@ -0,0 +1,160 @@ +# Release 0.4.1 (2022-06-23) + +- [Fewer `clone` calls are used when reducing a new `Ratio<T>`][98]. +- [Conversions to floating point are better at avoiding underflow][104]. +- [`Ratio<T>` now implements `Default`][105], returning a zero value. + +**Contributors**: @cuviper, @lemmih, @MattX + +[98]: https://github.com/rust-num/num-rational/pull/98 +[104]: https://github.com/rust-num/num-rational/pull/104 +[105]: https://github.com/rust-num/num-rational/pull/105 + +# Release 0.4.0 (2021-03-05) + +- The optional `num-bigint` dependency is now 0.4. +- [The `Rational` alias for `Ratio<usize>` is now deprecated][92]. It is + recommended to use specific type sizes for numeric computation, like + `Rational32` and `Rational64`. + +**Contributors**: @cuviper, @vks + +[92]: https://github.com/rust-num/num-rational/pull/92 + +# Release 0.3.2 (2020-11-06) + +- [Fix always rebuilding with --remap-path-prefix][88] + +**Contributors**: @Nemo157 + +[88]: https://github.com/rust-num/num-rational/pull/88 + +# Release 0.3.1 (2020-10-29) + +- [Handle to_f64() with raw division by zero][83]. +- [Better document panic behaviour][84]. +- Clarify the license specification as "MIT OR Apache-2.0". + +**Contributors**: @cuviper, @zetok + +[83]: https://github.com/rust-num/num-rational/pull/83 +[84]: https://github.com/rust-num/num-rational/pull/84 + +# Release 0.3.0 (2020-06-13) + +### Enhancements + +- [`Ratio` now implements `ToPrimitive`][52]. +- [`Ratio` now implements additional formatting traits][56]: + - `Binary`, `Octal`, `LowerHex`, `UpperHex`, `LowerExp`, `UpperExp` +- [The `Pow` implementations have been expanded][70]. + - `Pow<BigInt>` and `Pow<BigUint>` are now implemented. + - `Pow<_> for &Ratio<T>` now uses `&T: Pow`. + - The inherent `pow` method now uses `&T: Pow`. + +### Breaking Changes + +- [`num-rational` now requires Rust 1.31 or greater][66]. + - The "i128" opt-in feature was removed, now always available. +- [The "num-bigint-std" feature replaces "bigint" with `std` enabled][80]. + - The "num-bigint" feature without `std` uses `alloc` on Rust 1.36+. + +**Contributors**: @cuviper, @MattX, @maxbla + +[52]: https://github.com/rust-num/num-rational/pull/52 +[56]: https://github.com/rust-num/num-rational/pull/56 +[66]: https://github.com/rust-num/num-rational/pull/66 +[70]: https://github.com/rust-num/num-rational/pull/70 +[80]: https://github.com/rust-num/num-rational/pull/80 + +# Release 0.2.4 (2020-03-17) + +- [Fixed `CheckedDiv` when both dividend and divisor are 0][74]. +- [Fixed `CheckedDiv` with `min_value()` numerators][76]. + +[74]: https://github.com/rust-num/num-rational/pull/74 +[76]: https://github.com/rust-num/num-rational/pull/76 + +# Release 0.2.3 (2020-01-09) + +- [`Ratio` now performs earlier reductions to avoid overflow with `+-*/%` operators][42]. +- [`Ratio::{new_raw, numer, denom}` are now `const fn` for Rust 1.31 and later][48]. +- [Updated the `autocfg` build dependency to 1.0][63]. + +**Contributors**: @cuviper, @dingelish, @jimbo1qaz, @maxbla + +[42]: https://github.com/rust-num/num-rational/pull/42 +[48]: https://github.com/rust-num/num-rational/pull/48 +[63]: https://github.com/rust-num/num-rational/pull/63 + +# Release 0.2.2 (2019-06-10) + +- [`Ratio` now implements `Zero::set_zero` and `One::set_one`][47]. + +**Contributors**: @cuviper, @ignatenkobrain, @vks + +[47]: https://github.com/rust-num/num-rational/pull/47 + +# Release 0.2.1 (2018-06-22) + +- Maintenance release to fix `html_root_url`. + +# Release 0.2.0 (2018-06-19) + +### Enhancements + +- [`Ratio` now implements `One::is_one` and the `Inv` trait][19]. +- [`Ratio` now implements `Sum` and `Product`][25]. +- [`Ratio` now supports `i128` and `u128` components][29] with Rust 1.26+. +- [`Ratio` now implements the `Pow` trait][21]. + +### Breaking Changes + +- [`num-rational` now requires rustc 1.15 or greater][18]. +- [There is now a `std` feature][23], enabled by default, along with the + implication that building *without* this feature makes this a `#![no_std]` + crate. A few methods now require `FloatCore` instead of `Float`. +- [The `serde` dependency has been updated to 1.0][24], and `rustc-serialize` + is no longer supported by `num-rational`. +- The optional `num-bigint` dependency has been updated to 0.2, and should be + enabled using the `bigint-std` feature. In the future, it may be possible + to use the `bigint` feature with `no_std`. + +**Contributors**: @clarcharr, @cuviper, @Emerentius, @robomancer-or, @vks + +[18]: https://github.com/rust-num/num-rational/pull/18 +[19]: https://github.com/rust-num/num-rational/pull/19 +[21]: https://github.com/rust-num/num-rational/pull/21 +[23]: https://github.com/rust-num/num-rational/pull/23 +[24]: https://github.com/rust-num/num-rational/pull/24 +[25]: https://github.com/rust-num/num-rational/pull/25 +[29]: https://github.com/rust-num/num-rational/pull/29 + + +# Release 0.1.42 (2018-02-08) + +- Maintenance release to update dependencies. + + +# Release 0.1.41 (2018-01-26) + +- [num-rational now has its own source repository][num-356] at [rust-num/num-rational][home]. +- [`Ratio` now implements `CheckedAdd`, `CheckedSub`, `CheckedMul`, and `CheckedDiv`][11]. +- [`Ratio` now implements `AddAssign`, `SubAssign`, `MulAssign`, `DivAssign`, and `RemAssign`][12] + with either `Ratio` or an integer on the right side. The non-assignment operators now also + accept integers as an operand. +- [`Ratio` operators now make fewer `clone()` calls][14]. + +Thanks to @c410-f3r, @cuviper, and @psimonyi for their contributions! + +[home]: https://github.com/rust-num/num-rational +[num-356]: https://github.com/rust-num/num/pull/356 +[11]: https://github.com/rust-num/num-rational/pull/11 +[12]: https://github.com/rust-num/num-rational/pull/12 +[14]: https://github.com/rust-num/num-rational/pull/14 + + +# Prior releases + +No prior release notes were kept. Thanks all the same to the many +contributors that have made this crate what it is! diff --git a/vendor/num-rational/build.rs b/vendor/num-rational/build.rs new file mode 100644 index 0000000..df5e310 --- /dev/null +++ b/vendor/num-rational/build.rs @@ -0,0 +1,8 @@ +fn main() { + let ac = autocfg::new(); + if ac.probe_expression("format!(\"{:e}\", 0_isize)") { + println!("cargo:rustc-cfg=has_int_exp_fmt"); + } + + autocfg::rerun_path("build.rs"); +} diff --git a/vendor/num-rational/src/lib.rs b/vendor/num-rational/src/lib.rs new file mode 100644 index 0000000..bf209ad --- /dev/null +++ b/vendor/num-rational/src/lib.rs @@ -0,0 +1,3106 @@ +// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Rational numbers +//! +//! ## Compatibility +//! +//! The `num-rational` crate is tested for rustc 1.31 and greater. + +#![doc(html_root_url = "https://docs.rs/num-rational/0.4")] +#![no_std] +// Ratio ops often use other "suspicious" ops +#![allow(clippy::suspicious_arithmetic_impl)] +#![allow(clippy::suspicious_op_assign_impl)] + +#[cfg(feature = "std")] +#[macro_use] +extern crate std; + +use core::cmp; +use core::fmt; +use core::fmt::{Binary, Display, Formatter, LowerExp, LowerHex, Octal, UpperExp, UpperHex}; +use core::hash::{Hash, Hasher}; +use core::ops::{Add, Div, Mul, Neg, Rem, ShlAssign, Sub}; +use core::str::FromStr; +#[cfg(feature = "std")] +use std::error::Error; + +#[cfg(feature = "num-bigint")] +use num_bigint::{BigInt, BigUint, Sign, ToBigInt}; + +use num_integer::Integer; +use num_traits::float::FloatCore; +use num_traits::ToPrimitive; +use num_traits::{ + Bounded, CheckedAdd, CheckedDiv, CheckedMul, CheckedSub, FromPrimitive, Inv, Num, NumCast, One, + Pow, Signed, Zero, +}; + +mod pow; + +/// Represents the ratio between two numbers. +#[derive(Copy, Clone, Debug)] +#[allow(missing_docs)] +pub struct Ratio<T> { + /// Numerator. + numer: T, + /// Denominator. + denom: T, +} + +/// Alias for a `Ratio` of machine-sized integers. +#[deprecated( + since = "0.4.0", + note = "it's better to use a specific size, like `Rational32` or `Rational64`" +)] +pub type Rational = Ratio<isize>; +/// Alias for a `Ratio` of 32-bit-sized integers. +pub type Rational32 = Ratio<i32>; +/// Alias for a `Ratio` of 64-bit-sized integers. +pub type Rational64 = Ratio<i64>; + +#[cfg(feature = "num-bigint")] +/// Alias for arbitrary precision rationals. +pub type BigRational = Ratio<BigInt>; + +/// These method are `const` for Rust 1.31 and later. +impl<T> Ratio<T> { + /// Creates a `Ratio` without checking for `denom == 0` or reducing. + /// + /// **There are several methods that will panic if used on a `Ratio` with + /// `denom == 0`.** + #[inline] + pub const fn new_raw(numer: T, denom: T) -> Ratio<T> { + Ratio { numer, denom } + } + + /// Gets an immutable reference to the numerator. + #[inline] + pub const fn numer(&self) -> &T { + &self.numer + } + + /// Gets an immutable reference to the denominator. + #[inline] + pub const fn denom(&self) -> &T { + &self.denom + } +} + +impl<T: Clone + Integer> Ratio<T> { + /// Creates a new `Ratio`. + /// + /// **Panics if `denom` is zero.** + #[inline] + pub fn new(numer: T, denom: T) -> Ratio<T> { + let mut ret = Ratio::new_raw(numer, denom); + ret.reduce(); + ret + } + + /// Creates a `Ratio` representing the integer `t`. + #[inline] + pub fn from_integer(t: T) -> Ratio<T> { + Ratio::new_raw(t, One::one()) + } + + /// Converts to an integer, rounding towards zero. + #[inline] + pub fn to_integer(&self) -> T { + self.trunc().numer + } + + /// Returns true if the rational number is an integer (denominator is 1). + #[inline] + pub fn is_integer(&self) -> bool { + self.denom.is_one() + } + + /// Puts self into lowest terms, with `denom` > 0. + /// + /// **Panics if `denom` is zero.** + fn reduce(&mut self) { + if self.denom.is_zero() { + panic!("denominator == 0"); + } + if self.numer.is_zero() { + self.denom.set_one(); + return; + } + if self.numer == self.denom { + self.set_one(); + return; + } + let g: T = self.numer.gcd(&self.denom); + + // FIXME(#5992): assignment operator overloads + // T: Clone + Integer != T: Clone + NumAssign + + #[inline] + fn replace_with<T: Zero>(x: &mut T, f: impl FnOnce(T) -> T) { + let y = core::mem::replace(x, T::zero()); + *x = f(y); + } + + // self.numer /= g; + replace_with(&mut self.numer, |x| x / g.clone()); + + // self.denom /= g; + replace_with(&mut self.denom, |x| x / g); + + // keep denom positive! + if self.denom < T::zero() { + replace_with(&mut self.numer, |x| T::zero() - x); + replace_with(&mut self.denom, |x| T::zero() - x); + } + } + + /// Returns a reduced copy of self. + /// + /// In general, it is not necessary to use this method, as the only + /// method of procuring a non-reduced fraction is through `new_raw`. + /// + /// **Panics if `denom` is zero.** + pub fn reduced(&self) -> Ratio<T> { + let mut ret = self.clone(); + ret.reduce(); + ret + } + + /// Returns the reciprocal. + /// + /// **Panics if the `Ratio` is zero.** + #[inline] + pub fn recip(&self) -> Ratio<T> { + self.clone().into_recip() + } + + #[inline] + fn into_recip(self) -> Ratio<T> { + match self.numer.cmp(&T::zero()) { + cmp::Ordering::Equal => panic!("division by zero"), + cmp::Ordering::Greater => Ratio::new_raw(self.denom, self.numer), + cmp::Ordering::Less => Ratio::new_raw(T::zero() - self.denom, T::zero() - self.numer), + } + } + + /// Rounds towards minus infinity. + #[inline] + pub fn floor(&self) -> Ratio<T> { + if *self < Zero::zero() { + let one: T = One::one(); + Ratio::from_integer( + (self.numer.clone() - self.denom.clone() + one) / self.denom.clone(), + ) + } else { + Ratio::from_integer(self.numer.clone() / self.denom.clone()) + } + } + + /// Rounds towards plus infinity. + #[inline] + pub fn ceil(&self) -> Ratio<T> { + if *self < Zero::zero() { + Ratio::from_integer(self.numer.clone() / self.denom.clone()) + } else { + let one: T = One::one(); + Ratio::from_integer( + (self.numer.clone() + self.denom.clone() - one) / self.denom.clone(), + ) + } + } + + /// Rounds to the nearest integer. Rounds half-way cases away from zero. + #[inline] + pub fn round(&self) -> Ratio<T> { + let zero: Ratio<T> = Zero::zero(); + let one: T = One::one(); + let two: T = one.clone() + one.clone(); + + // Find unsigned fractional part of rational number + let mut fractional = self.fract(); + if fractional < zero { + fractional = zero - fractional + }; + + // The algorithm compares the unsigned fractional part with 1/2, that + // is, a/b >= 1/2, or a >= b/2. For odd denominators, we use + // a >= (b/2)+1. This avoids overflow issues. + let half_or_larger = if fractional.denom.is_even() { + fractional.numer >= fractional.denom / two + } else { + fractional.numer >= (fractional.denom / two) + one + }; + + if half_or_larger { + let one: Ratio<T> = One::one(); + if *self >= Zero::zero() { + self.trunc() + one + } else { + self.trunc() - one + } + } else { + self.trunc() + } + } + + /// Rounds towards zero. + #[inline] + pub fn trunc(&self) -> Ratio<T> { + Ratio::from_integer(self.numer.clone() / self.denom.clone()) + } + + /// Returns the fractional part of a number, with division rounded towards zero. + /// + /// Satisfies `self == self.trunc() + self.fract()`. + #[inline] + pub fn fract(&self) -> Ratio<T> { + Ratio::new_raw(self.numer.clone() % self.denom.clone(), self.denom.clone()) + } + + /// Raises the `Ratio` to the power of an exponent. + #[inline] + pub fn pow(&self, expon: i32) -> Ratio<T> + where + for<'a> &'a T: Pow<u32, Output = T>, + { + Pow::pow(self, expon) + } +} + +#[cfg(feature = "num-bigint")] +impl Ratio<BigInt> { + /// Converts a float into a rational number. + pub fn from_float<T: FloatCore>(f: T) -> Option<BigRational> { + if !f.is_finite() { + return None; + } + let (mantissa, exponent, sign) = f.integer_decode(); + let bigint_sign = if sign == 1 { Sign::Plus } else { Sign::Minus }; + if exponent < 0 { + let one: BigInt = One::one(); + let denom: BigInt = one << ((-exponent) as usize); + let numer: BigUint = FromPrimitive::from_u64(mantissa).unwrap(); + Some(Ratio::new(BigInt::from_biguint(bigint_sign, numer), denom)) + } else { + let mut numer: BigUint = FromPrimitive::from_u64(mantissa).unwrap(); + numer <<= exponent as usize; + Some(Ratio::from_integer(BigInt::from_biguint( + bigint_sign, + numer, + ))) + } + } +} + +impl<T: Clone + Integer> Default for Ratio<T> { + /// Returns zero + fn default() -> Self { + Ratio::zero() + } +} + +// From integer +impl<T> From<T> for Ratio<T> +where + T: Clone + Integer, +{ + fn from(x: T) -> Ratio<T> { + Ratio::from_integer(x) + } +} + +// From pair (through the `new` constructor) +impl<T> From<(T, T)> for Ratio<T> +where + T: Clone + Integer, +{ + fn from(pair: (T, T)) -> Ratio<T> { + Ratio::new(pair.0, pair.1) + } +} + +// Comparisons + +// Mathematically, comparing a/b and c/d is the same as comparing a*d and b*c, but it's very easy +// for those multiplications to overflow fixed-size integers, so we need to take care. + +impl<T: Clone + Integer> Ord for Ratio<T> { + #[inline] + fn cmp(&self, other: &Self) -> cmp::Ordering { + // With equal denominators, the numerators can be directly compared + if self.denom == other.denom { + let ord = self.numer.cmp(&other.numer); + return if self.denom < T::zero() { + ord.reverse() + } else { + ord + }; + } + + // With equal numerators, the denominators can be inversely compared + if self.numer == other.numer { + if self.numer.is_zero() { + return cmp::Ordering::Equal; + } + let ord = self.denom.cmp(&other.denom); + return if self.numer < T::zero() { + ord + } else { + ord.reverse() + }; + } + + // Unfortunately, we don't have CheckedMul to try. That could sometimes avoid all the + // division below, or even always avoid it for BigInt and BigUint. + // FIXME- future breaking change to add Checked* to Integer? + + // Compare as floored integers and remainders + let (self_int, self_rem) = self.numer.div_mod_floor(&self.denom); + let (other_int, other_rem) = other.numer.div_mod_floor(&other.denom); + match self_int.cmp(&other_int) { + cmp::Ordering::Greater => cmp::Ordering::Greater, + cmp::Ordering::Less => cmp::Ordering::Less, + cmp::Ordering::Equal => { + match (self_rem.is_zero(), other_rem.is_zero()) { + (true, true) => cmp::Ordering::Equal, + (true, false) => cmp::Ordering::Less, + (false, true) => cmp::Ordering::Greater, + (false, false) => { + // Compare the reciprocals of the remaining fractions in reverse + let self_recip = Ratio::new_raw(self.denom.clone(), self_rem); + let other_recip = Ratio::new_raw(other.denom.clone(), other_rem); + self_recip.cmp(&other_recip).reverse() + } + } + } + } + } +} + +impl<T: Clone + Integer> PartialOrd for Ratio<T> { + #[inline] + fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> { + Some(self.cmp(other)) + } +} + +impl<T: Clone + Integer> PartialEq for Ratio<T> { + #[inline] + fn eq(&self, other: &Self) -> bool { + self.cmp(other) == cmp::Ordering::Equal + } +} + +impl<T: Clone + Integer> Eq for Ratio<T> {} + +// NB: We can't just `#[derive(Hash)]`, because it needs to agree +// with `Eq` even for non-reduced ratios. +impl<T: Clone + Integer + Hash> Hash for Ratio<T> { + fn hash<H: Hasher>(&self, state: &mut H) { + recurse(&self.numer, &self.denom, state); + + fn recurse<T: Integer + Hash, H: Hasher>(numer: &T, denom: &T, state: &mut H) { + if !denom.is_zero() { + let (int, rem) = numer.div_mod_floor(denom); + int.hash(state); + recurse(denom, &rem, state); + } else { + denom.hash(state); + } + } + } +} + +mod iter_sum_product { + use crate::Ratio; + use core::iter::{Product, Sum}; + use num_integer::Integer; + use num_traits::{One, Zero}; + + impl<T: Integer + Clone> Sum for Ratio<T> { + fn sum<I>(iter: I) -> Self + where + I: Iterator<Item = Ratio<T>>, + { + iter.fold(Self::zero(), |sum, num| sum + num) + } + } + + impl<'a, T: Integer + Clone> Sum<&'a Ratio<T>> for Ratio<T> { + fn sum<I>(iter: I) -> Self + where + I: Iterator<Item = &'a Ratio<T>>, + { + iter.fold(Self::zero(), |sum, num| sum + num) + } + } + + impl<T: Integer + Clone> Product for Ratio<T> { + fn product<I>(iter: I) -> Self + where + I: Iterator<Item = Ratio<T>>, + { + iter.fold(Self::one(), |prod, num| prod * num) + } + } + + impl<'a, T: Integer + Clone> Product<&'a Ratio<T>> for Ratio<T> { + fn product<I>(iter: I) -> Self + where + I: Iterator<Item = &'a Ratio<T>>, + { + iter.fold(Self::one(), |prod, num| prod * num) + } + } +} + +mod opassign { + use core::ops::{AddAssign, DivAssign, MulAssign, RemAssign, SubAssign}; + + use crate::Ratio; + use num_integer::Integer; + use num_traits::NumAssign; + + impl<T: Clone + Integer + NumAssign> AddAssign for Ratio<T> { + fn add_assign(&mut self, other: Ratio<T>) { + if self.denom == other.denom { + self.numer += other.numer + } else { + let lcm = self.denom.lcm(&other.denom); + let lhs_numer = self.numer.clone() * (lcm.clone() / self.denom.clone()); + let rhs_numer = other.numer * (lcm.clone() / other.denom); + self.numer = lhs_numer + rhs_numer; + self.denom = lcm; + } + self.reduce(); + } + } + + // (a/b) / (c/d) = (a/gcd_ac)*(d/gcd_bd) / ((c/gcd_ac)*(b/gcd_bd)) + impl<T: Clone + Integer + NumAssign> DivAssign for Ratio<T> { + fn div_assign(&mut self, other: Ratio<T>) { + let gcd_ac = self.numer.gcd(&other.numer); + let gcd_bd = self.denom.gcd(&other.denom); + self.numer /= gcd_ac.clone(); + self.numer *= other.denom / gcd_bd.clone(); + self.denom /= gcd_bd; + self.denom *= other.numer / gcd_ac; + self.reduce(); // TODO: remove this line. see #8. + } + } + + // a/b * c/d = (a/gcd_ad)*(c/gcd_bc) / ((d/gcd_ad)*(b/gcd_bc)) + impl<T: Clone + Integer + NumAssign> MulAssign for Ratio<T> { + fn mul_assign(&mut self, other: Ratio<T>) { + let gcd_ad = self.numer.gcd(&other.denom); + let gcd_bc = self.denom.gcd(&other.numer); + self.numer /= gcd_ad.clone(); + self.numer *= other.numer / gcd_bc.clone(); + self.denom /= gcd_bc; + self.denom *= other.denom / gcd_ad; + self.reduce(); // TODO: remove this line. see #8. + } + } + + impl<T: Clone + Integer + NumAssign> RemAssign for Ratio<T> { + fn rem_assign(&mut self, other: Ratio<T>) { + if self.denom == other.denom { + self.numer %= other.numer + } else { + let lcm = self.denom.lcm(&other.denom); + let lhs_numer = self.numer.clone() * (lcm.clone() / self.denom.clone()); + let rhs_numer = other.numer * (lcm.clone() / other.denom); + self.numer = lhs_numer % rhs_numer; + self.denom = lcm; + } + self.reduce(); + } + } + + impl<T: Clone + Integer + NumAssign> SubAssign for Ratio<T> { + fn sub_assign(&mut self, other: Ratio<T>) { + if self.denom == other.denom { + self.numer -= other.numer + } else { + let lcm = self.denom.lcm(&other.denom); + let lhs_numer = self.numer.clone() * (lcm.clone() / self.denom.clone()); + let rhs_numer = other.numer * (lcm.clone() / other.denom); + self.numer = lhs_numer - rhs_numer; + self.denom = lcm; + } + self.reduce(); + } + } + + // a/b + c/1 = (a*1 + b*c) / (b*1) = (a + b*c) / b + impl<T: Clone + Integer + NumAssign> AddAssign<T> for Ratio<T> { + fn add_assign(&mut self, other: T) { + self.numer += self.denom.clone() * other; + self.reduce(); + } + } + + impl<T: Clone + Integer + NumAssign> DivAssign<T> for Ratio<T> { + fn div_assign(&mut self, other: T) { + let gcd = self.numer.gcd(&other); + self.numer /= gcd.clone(); + self.denom *= other / gcd; + self.reduce(); // TODO: remove this line. see #8. + } + } + + impl<T: Clone + Integer + NumAssign> MulAssign<T> for Ratio<T> { + fn mul_assign(&mut self, other: T) { + let gcd = self.denom.gcd(&other); + self.denom /= gcd.clone(); + self.numer *= other / gcd; + self.reduce(); // TODO: remove this line. see #8. + } + } + + // a/b % c/1 = (a*1 % b*c) / (b*1) = (a % b*c) / b + impl<T: Clone + Integer + NumAssign> RemAssign<T> for Ratio<T> { + fn rem_assign(&mut self, other: T) { + self.numer %= self.denom.clone() * other; + self.reduce(); + } + } + + // a/b - c/1 = (a*1 - b*c) / (b*1) = (a - b*c) / b + impl<T: Clone + Integer + NumAssign> SubAssign<T> for Ratio<T> { + fn sub_assign(&mut self, other: T) { + self.numer -= self.denom.clone() * other; + self.reduce(); + } + } + + macro_rules! forward_op_assign { + (impl $imp:ident, $method:ident) => { + impl<'a, T: Clone + Integer + NumAssign> $imp<&'a Ratio<T>> for Ratio<T> { + #[inline] + fn $method(&mut self, other: &Ratio<T>) { + self.$method(other.clone()) + } + } + impl<'a, T: Clone + Integer + NumAssign> $imp<&'a T> for Ratio<T> { + #[inline] + fn $method(&mut self, other: &T) { + self.$method(other.clone()) + } + } + }; + } + + forward_op_assign!(impl AddAssign, add_assign); + forward_op_assign!(impl DivAssign, div_assign); + forward_op_assign!(impl MulAssign, mul_assign); + forward_op_assign!(impl RemAssign, rem_assign); + forward_op_assign!(impl SubAssign, sub_assign); +} + +macro_rules! forward_ref_ref_binop { + (impl $imp:ident, $method:ident) => { + impl<'a, 'b, T: Clone + Integer> $imp<&'b Ratio<T>> for &'a Ratio<T> { + type Output = Ratio<T>; + + #[inline] + fn $method(self, other: &'b Ratio<T>) -> Ratio<T> { + self.clone().$method(other.clone()) + } + } + impl<'a, 'b, T: Clone + Integer> $imp<&'b T> for &'a Ratio<T> { + type Output = Ratio<T>; + + #[inline] + fn $method(self, other: &'b T) -> Ratio<T> { + self.clone().$method(other.clone()) + } + } + }; +} + +macro_rules! forward_ref_val_binop { + (impl $imp:ident, $method:ident) => { + impl<'a, T> $imp<Ratio<T>> for &'a Ratio<T> + where + T: Clone + Integer, + { + type Output = Ratio<T>; + + #[inline] + fn $method(self, other: Ratio<T>) -> Ratio<T> { + self.clone().$method(other) + } + } + impl<'a, T> $imp<T> for &'a Ratio<T> + where + T: Clone + Integer, + { + type Output = Ratio<T>; + + #[inline] + fn $method(self, other: T) -> Ratio<T> { + self.clone().$method(other) + } + } + }; +} + +macro_rules! forward_val_ref_binop { + (impl $imp:ident, $method:ident) => { + impl<'a, T> $imp<&'a Ratio<T>> for Ratio<T> + where + T: Clone + Integer, + { + type Output = Ratio<T>; + + #[inline] + fn $method(self, other: &Ratio<T>) -> Ratio<T> { + self.$method(other.clone()) + } + } + impl<'a, T> $imp<&'a T> for Ratio<T> + where + T: Clone + Integer, + { + type Output = Ratio<T>; + + #[inline] + fn $method(self, other: &T) -> Ratio<T> { + self.$method(other.clone()) + } + } + }; +} + +macro_rules! forward_all_binop { + (impl $imp:ident, $method:ident) => { + forward_ref_ref_binop!(impl $imp, $method); + forward_ref_val_binop!(impl $imp, $method); + forward_val_ref_binop!(impl $imp, $method); + }; +} + +// Arithmetic +forward_all_binop!(impl Mul, mul); +// a/b * c/d = (a/gcd_ad)*(c/gcd_bc) / ((d/gcd_ad)*(b/gcd_bc)) +impl<T> Mul<Ratio<T>> for Ratio<T> +where + T: Clone + Integer, +{ + type Output = Ratio<T>; + #[inline] + fn mul(self, rhs: Ratio<T>) -> Ratio<T> { + let gcd_ad = self.numer.gcd(&rhs.denom); + let gcd_bc = self.denom.gcd(&rhs.numer); + Ratio::new( + self.numer / gcd_ad.clone() * (rhs.numer / gcd_bc.clone()), + self.denom / gcd_bc * (rhs.denom / gcd_ad), + ) + } +} +// a/b * c/1 = (a*c) / (b*1) = (a*c) / b +impl<T> Mul<T> for Ratio<T> +where + T: Clone + Integer, +{ + type Output = Ratio<T>; + #[inline] + fn mul(self, rhs: T) -> Ratio<T> { + let gcd = self.denom.gcd(&rhs); + Ratio::new(self.numer * (rhs / gcd.clone()), self.denom / gcd) + } +} + +forward_all_binop!(impl Div, div); +// (a/b) / (c/d) = (a/gcd_ac)*(d/gcd_bd) / ((c/gcd_ac)*(b/gcd_bd)) +impl<T> Div<Ratio<T>> for Ratio<T> +where + T: Clone + Integer, +{ + type Output = Ratio<T>; + + #[inline] + fn div(self, rhs: Ratio<T>) -> Ratio<T> { + let gcd_ac = self.numer.gcd(&rhs.numer); + let gcd_bd = self.denom.gcd(&rhs.denom); + Ratio::new( + self.numer / gcd_ac.clone() * (rhs.denom / gcd_bd.clone()), + self.denom / gcd_bd * (rhs.numer / gcd_ac), + ) + } +} +// (a/b) / (c/1) = (a*1) / (b*c) = a / (b*c) +impl<T> Div<T> for Ratio<T> +where + T: Clone + Integer, +{ + type Output = Ratio<T>; + + #[inline] + fn div(self, rhs: T) -> Ratio<T> { + let gcd = self.numer.gcd(&rhs); + Ratio::new(self.numer / gcd.clone(), self.denom * (rhs / gcd)) + } +} + +macro_rules! arith_impl { + (impl $imp:ident, $method:ident) => { + forward_all_binop!(impl $imp, $method); + // Abstracts a/b `op` c/d = (a*lcm/b `op` c*lcm/d)/lcm where lcm = lcm(b,d) + impl<T: Clone + Integer> $imp<Ratio<T>> for Ratio<T> { + type Output = Ratio<T>; + #[inline] + fn $method(self, rhs: Ratio<T>) -> Ratio<T> { + if self.denom == rhs.denom { + return Ratio::new(self.numer.$method(rhs.numer), rhs.denom); + } + let lcm = self.denom.lcm(&rhs.denom); + let lhs_numer = self.numer * (lcm.clone() / self.denom); + let rhs_numer = rhs.numer * (lcm.clone() / rhs.denom); + Ratio::new(lhs_numer.$method(rhs_numer), lcm) + } + } + // Abstracts the a/b `op` c/1 = (a*1 `op` b*c) / (b*1) = (a `op` b*c) / b pattern + impl<T: Clone + Integer> $imp<T> for Ratio<T> { + type Output = Ratio<T>; + #[inline] + fn $method(self, rhs: T) -> Ratio<T> { + Ratio::new(self.numer.$method(self.denom.clone() * rhs), self.denom) + } + } + }; +} + +arith_impl!(impl Add, add); +arith_impl!(impl Sub, sub); +arith_impl!(impl Rem, rem); + +// a/b * c/d = (a*c)/(b*d) +impl<T> CheckedMul for Ratio<T> +where + T: Clone + Integer + CheckedMul, +{ + #[inline] + fn checked_mul(&self, rhs: &Ratio<T>) -> Option<Ratio<T>> { + let gcd_ad = self.numer.gcd(&rhs.denom); + let gcd_bc = self.denom.gcd(&rhs.numer); + Some(Ratio::new( + (self.numer.clone() / gcd_ad.clone()) + .checked_mul(&(rhs.numer.clone() / gcd_bc.clone()))?, + (self.denom.clone() / gcd_bc).checked_mul(&(rhs.denom.clone() / gcd_ad))?, + )) + } +} + +// (a/b) / (c/d) = (a*d)/(b*c) +impl<T> CheckedDiv for Ratio<T> +where + T: Clone + Integer + CheckedMul, +{ + #[inline] + fn checked_div(&self, rhs: &Ratio<T>) -> Option<Ratio<T>> { + if rhs.is_zero() { + return None; + } + let (numer, denom) = if self.denom == rhs.denom { + (self.numer.clone(), rhs.numer.clone()) + } else if self.numer == rhs.numer { + (rhs.denom.clone(), self.denom.clone()) + } else { + let gcd_ac = self.numer.gcd(&rhs.numer); + let gcd_bd = self.denom.gcd(&rhs.denom); + ( + (self.numer.clone() / gcd_ac.clone()) + .checked_mul(&(rhs.denom.clone() / gcd_bd.clone()))?, + (self.denom.clone() / gcd_bd).checked_mul(&(rhs.numer.clone() / gcd_ac))?, + ) + }; + // Manual `reduce()`, avoiding sharp edges + if denom.is_zero() { + None + } else if numer.is_zero() { + Some(Self::zero()) + } else if numer == denom { + Some(Self::one()) + } else { + let g = numer.gcd(&denom); + let numer = numer / g.clone(); + let denom = denom / g; + let raw = if denom < T::zero() { + // We need to keep denom positive, but 2's-complement MIN may + // overflow negation -- instead we can check multiplying -1. + let n1 = T::zero() - T::one(); + Ratio::new_raw(numer.checked_mul(&n1)?, denom.checked_mul(&n1)?) + } else { + Ratio::new_raw(numer, denom) + }; + Some(raw) + } + } +} + +// As arith_impl! but for Checked{Add,Sub} traits +macro_rules! checked_arith_impl { + (impl $imp:ident, $method:ident) => { + impl<T: Clone + Integer + CheckedMul + $imp> $imp for Ratio<T> { + #[inline] + fn $method(&self, rhs: &Ratio<T>) -> Option<Ratio<T>> { + let gcd = self.denom.clone().gcd(&rhs.denom); + let lcm = (self.denom.clone() / gcd.clone()).checked_mul(&rhs.denom)?; + let lhs_numer = (lcm.clone() / self.denom.clone()).checked_mul(&self.numer)?; + let rhs_numer = (lcm.clone() / rhs.denom.clone()).checked_mul(&rhs.numer)?; + Some(Ratio::new(lhs_numer.$method(&rhs_numer)?, lcm)) + } + } + }; +} + +// a/b + c/d = (lcm/b*a + lcm/d*c)/lcm, where lcm = lcm(b,d) +checked_arith_impl!(impl CheckedAdd, checked_add); + +// a/b - c/d = (lcm/b*a - lcm/d*c)/lcm, where lcm = lcm(b,d) +checked_arith_impl!(impl CheckedSub, checked_sub); + +impl<T> Neg for Ratio<T> +where + T: Clone + Integer + Neg<Output = T>, +{ + type Output = Ratio<T>; + + #[inline] + fn neg(self) -> Ratio<T> { + Ratio::new_raw(-self.numer, self.denom) + } +} + +impl<'a, T> Neg for &'a Ratio<T> +where + T: Clone + Integer + Neg<Output = T>, +{ + type Output = Ratio<T>; + + #[inline] + fn neg(self) -> Ratio<T> { + -self.clone() + } +} + +impl<T> Inv for Ratio<T> +where + T: Clone + Integer, +{ + type Output = Ratio<T>; + + #[inline] + fn inv(self) -> Ratio<T> { + self.recip() + } +} + +impl<'a, T> Inv for &'a Ratio<T> +where + T: Clone + Integer, +{ + type Output = Ratio<T>; + + #[inline] + fn inv(self) -> Ratio<T> { + self.recip() + } +} + +// Constants +impl<T: Clone + Integer> Zero for Ratio<T> { + #[inline] + fn zero() -> Ratio<T> { + Ratio::new_raw(Zero::zero(), One::one()) + } + + #[inline] + fn is_zero(&self) -> bool { + self.numer.is_zero() + } + + #[inline] + fn set_zero(&mut self) { + self.numer.set_zero(); + self.denom.set_one(); + } +} + +impl<T: Clone + Integer> One for Ratio<T> { + #[inline] + fn one() -> Ratio<T> { + Ratio::new_raw(One::one(), One::one()) + } + + #[inline] + fn is_one(&self) -> bool { + self.numer == self.denom + } + + #[inline] + fn set_one(&mut self) { + self.numer.set_one(); + self.denom.set_one(); + } +} + +impl<T: Clone + Integer> Num for Ratio<T> { + type FromStrRadixErr = ParseRatioError; + + /// Parses `numer/denom` where the numbers are in base `radix`. + fn from_str_radix(s: &str, radix: u32) -> Result<Ratio<T>, ParseRatioError> { + if s.splitn(2, '/').count() == 2 { + let mut parts = s.splitn(2, '/').map(|ss| { + T::from_str_radix(ss, radix).map_err(|_| ParseRatioError { + kind: RatioErrorKind::ParseError, + }) + }); + let numer: T = parts.next().unwrap()?; + let denom: T = parts.next().unwrap()?; + if denom.is_zero() { + Err(ParseRatioError { + kind: RatioErrorKind::ZeroDenominator, + }) + } else { + Ok(Ratio::new(numer, denom)) + } + } else { + Err(ParseRatioError { + kind: RatioErrorKind::ParseError, + }) + } + } +} + +impl<T: Clone + Integer + Signed> Signed for Ratio<T> { + #[inline] + fn abs(&self) -> Ratio<T> { + if self.is_negative() { + -self.clone() + } else { + self.clone() + } + } + + #[inline] + fn abs_sub(&self, other: &Ratio<T>) -> Ratio<T> { + if *self <= *other { + Zero::zero() + } else { + self - other + } + } + + #[inline] + fn signum(&self) -> Ratio<T> { + if self.is_positive() { + Self::one() + } else if self.is_zero() { + Self::zero() + } else { + -Self::one() + } + } + + #[inline] + fn is_positive(&self) -> bool { + (self.numer.is_positive() && self.denom.is_positive()) + || (self.numer.is_negative() && self.denom.is_negative()) + } + + #[inline] + fn is_negative(&self) -> bool { + (self.numer.is_negative() && self.denom.is_positive()) + || (self.numer.is_positive() && self.denom.is_negative()) + } +} + +// String conversions +macro_rules! impl_formatting { + ($fmt_trait:ident, $prefix:expr, $fmt_str:expr, $fmt_alt:expr) => { + impl<T: $fmt_trait + Clone + Integer> $fmt_trait for Ratio<T> { + #[cfg(feature = "std")] + fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result { + let pre_pad = if self.denom.is_one() { + format!($fmt_str, self.numer) + } else { + if f.alternate() { + format!(concat!($fmt_str, "/", $fmt_alt), self.numer, self.denom) + } else { + format!(concat!($fmt_str, "/", $fmt_str), self.numer, self.denom) + } + }; + // TODO: replace with strip_prefix, when stabalized + let (pre_pad, non_negative) = { + if pre_pad.starts_with("-") { + (&pre_pad[1..], false) + } else { + (&pre_pad[..], true) + } + }; + f.pad_integral(non_negative, $prefix, pre_pad) + } + #[cfg(not(feature = "std"))] + fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result { + let plus = if f.sign_plus() && self.numer >= T::zero() { + "+" + } else { + "" + }; + if self.denom.is_one() { + if f.alternate() { + write!(f, concat!("{}", $fmt_alt), plus, self.numer) + } else { + write!(f, concat!("{}", $fmt_str), plus, self.numer) + } + } else { + if f.alternate() { + write!( + f, + concat!("{}", $fmt_alt, "/", $fmt_alt), + plus, self.numer, self.denom + ) + } else { + write!( + f, + concat!("{}", $fmt_str, "/", $fmt_str), + plus, self.numer, self.denom + ) + } + } + } + } + }; +} + +impl_formatting!(Display, "", "{}", "{:#}"); +impl_formatting!(Octal, "0o", "{:o}", "{:#o}"); +impl_formatting!(Binary, "0b", "{:b}", "{:#b}"); +impl_formatting!(LowerHex, "0x", "{:x}", "{:#x}"); +impl_formatting!(UpperHex, "0x", "{:X}", "{:#X}"); +impl_formatting!(LowerExp, "", "{:e}", "{:#e}"); +impl_formatting!(UpperExp, "", "{:E}", "{:#E}"); + +impl<T: FromStr + Clone + Integer> FromStr for Ratio<T> { + type Err = ParseRatioError; + + /// Parses `numer/denom` or just `numer`. + fn from_str(s: &str) -> Result<Ratio<T>, ParseRatioError> { + let mut split = s.splitn(2, '/'); + + let n = split.next().ok_or(ParseRatioError { + kind: RatioErrorKind::ParseError, + })?; + let num = FromStr::from_str(n).map_err(|_| ParseRatioError { + kind: RatioErrorKind::ParseError, + })?; + + let d = split.next().unwrap_or("1"); + let den = FromStr::from_str(d).map_err(|_| ParseRatioError { + kind: RatioErrorKind::ParseError, + })?; + + if Zero::is_zero(&den) { + Err(ParseRatioError { + kind: RatioErrorKind::ZeroDenominator, + }) + } else { + Ok(Ratio::new(num, den)) + } + } +} + +impl<T> Into<(T, T)> for Ratio<T> { + fn into(self) -> (T, T) { + (self.numer, self.denom) + } +} + +#[cfg(feature = "serde")] +impl<T> serde::Serialize for Ratio<T> +where + T: serde::Serialize + Clone + Integer + PartialOrd, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: serde::Serializer, + { + (self.numer(), self.denom()).serialize(serializer) + } +} + +#[cfg(feature = "serde")] +impl<'de, T> serde::Deserialize<'de> for Ratio<T> +where + T: serde::Deserialize<'de> + Clone + Integer + PartialOrd, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: serde::Deserializer<'de>, + { + use serde::de::Error; + use serde::de::Unexpected; + let (numer, denom): (T, T) = serde::Deserialize::deserialize(deserializer)?; + if denom.is_zero() { + Err(Error::invalid_value( + Unexpected::Signed(0), + &"a ratio with non-zero denominator", + )) + } else { + Ok(Ratio::new_raw(numer, denom)) + } + } +} + +// FIXME: Bubble up specific errors +#[derive(Copy, Clone, Debug, PartialEq)] +pub struct ParseRatioError { + kind: RatioErrorKind, +} + +#[derive(Copy, Clone, Debug, PartialEq)] +enum RatioErrorKind { + ParseError, + ZeroDenominator, +} + +impl fmt::Display for ParseRatioError { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.kind.description().fmt(f) + } +} + +#[cfg(feature = "std")] +impl Error for ParseRatioError { + #[allow(deprecated)] + fn description(&self) -> &str { + self.kind.description() + } +} + +impl RatioErrorKind { + fn description(&self) -> &'static str { + match *self { + RatioErrorKind::ParseError => "failed to parse integer", + RatioErrorKind::ZeroDenominator => "zero value denominator", + } + } +} + +#[cfg(feature = "num-bigint")] +impl FromPrimitive for Ratio<BigInt> { + fn from_i64(n: i64) -> Option<Self> { + Some(Ratio::from_integer(n.into())) + } + + fn from_i128(n: i128) -> Option<Self> { + Some(Ratio::from_integer(n.into())) + } + + fn from_u64(n: u64) -> Option<Self> { + Some(Ratio::from_integer(n.into())) + } + + fn from_u128(n: u128) -> Option<Self> { + Some(Ratio::from_integer(n.into())) + } + + fn from_f32(n: f32) -> Option<Self> { + Ratio::from_float(n) + } + + fn from_f64(n: f64) -> Option<Self> { + Ratio::from_float(n) + } +} + +macro_rules! from_primitive_integer { + ($typ:ty, $approx:ident) => { + impl FromPrimitive for Ratio<$typ> { + fn from_i64(n: i64) -> Option<Self> { + <$typ as FromPrimitive>::from_i64(n).map(Ratio::from_integer) + } + + fn from_i128(n: i128) -> Option<Self> { + <$typ as FromPrimitive>::from_i128(n).map(Ratio::from_integer) + } + + fn from_u64(n: u64) -> Option<Self> { + <$typ as FromPrimitive>::from_u64(n).map(Ratio::from_integer) + } + + fn from_u128(n: u128) -> Option<Self> { + <$typ as FromPrimitive>::from_u128(n).map(Ratio::from_integer) + } + + fn from_f32(n: f32) -> Option<Self> { + $approx(n, 10e-20, 30) + } + + fn from_f64(n: f64) -> Option<Self> { + $approx(n, 10e-20, 30) + } + } + }; +} + +from_primitive_integer!(i8, approximate_float); +from_primitive_integer!(i16, approximate_float); +from_primitive_integer!(i32, approximate_float); +from_primitive_integer!(i64, approximate_float); +from_primitive_integer!(i128, approximate_float); +from_primitive_integer!(isize, approximate_float); + +from_primitive_integer!(u8, approximate_float_unsigned); +from_primitive_integer!(u16, approximate_float_unsigned); +from_primitive_integer!(u32, approximate_float_unsigned); +from_primitive_integer!(u64, approximate_float_unsigned); +from_primitive_integer!(u128, approximate_float_unsigned); +from_primitive_integer!(usize, approximate_float_unsigned); + +impl<T: Integer + Signed + Bounded + NumCast + Clone> Ratio<T> { + pub fn approximate_float<F: FloatCore + NumCast>(f: F) -> Option<Ratio<T>> { + // 1/10e-20 < 1/2**32 which seems like a good default, and 30 seems + // to work well. Might want to choose something based on the types in the future, e.g. + // T::max().recip() and T::bits() or something similar. + let epsilon = <F as NumCast>::from(10e-20).expect("Can't convert 10e-20"); + approximate_float(f, epsilon, 30) + } +} + +fn approximate_float<T, F>(val: F, max_error: F, max_iterations: usize) -> Option<Ratio<T>> +where + T: Integer + Signed + Bounded + NumCast + Clone, + F: FloatCore + NumCast, +{ + let negative = val.is_sign_negative(); + let abs_val = val.abs(); + + let r = approximate_float_unsigned(abs_val, max_error, max_iterations)?; + + // Make negative again if needed + Some(if negative { r.neg() } else { r }) +} + +// No Unsigned constraint because this also works on positive integers and is called +// like that, see above +fn approximate_float_unsigned<T, F>(val: F, max_error: F, max_iterations: usize) -> Option<Ratio<T>> +where + T: Integer + Bounded + NumCast + Clone, + F: FloatCore + NumCast, +{ + // Continued fractions algorithm + // http://mathforum.org/dr.math/faq/faq.fractions.html#decfrac + + if val < F::zero() || val.is_nan() { + return None; + } + + let mut q = val; + let mut n0 = T::zero(); + let mut d0 = T::one(); + let mut n1 = T::one(); + let mut d1 = T::zero(); + + let t_max = T::max_value(); + let t_max_f = <F as NumCast>::from(t_max.clone())?; + + // 1/epsilon > T::MAX + let epsilon = t_max_f.recip(); + + // Overflow + if q > t_max_f { + return None; + } + + for _ in 0..max_iterations { + let a = match <T as NumCast>::from(q) { + None => break, + Some(a) => a, + }; + + let a_f = match <F as NumCast>::from(a.clone()) { + None => break, + Some(a_f) => a_f, + }; + let f = q - a_f; + + // Prevent overflow + if !a.is_zero() + && (n1 > t_max.clone() / a.clone() + || d1 > t_max.clone() / a.clone() + || a.clone() * n1.clone() > t_max.clone() - n0.clone() + || a.clone() * d1.clone() > t_max.clone() - d0.clone()) + { + break; + } + + let n = a.clone() * n1.clone() + n0.clone(); + let d = a.clone() * d1.clone() + d0.clone(); + + n0 = n1; + d0 = d1; + n1 = n.clone(); + d1 = d.clone(); + + // Simplify fraction. Doing so here instead of at the end + // allows us to get closer to the target value without overflows + let g = Integer::gcd(&n1, &d1); + if !g.is_zero() { + n1 = n1 / g.clone(); + d1 = d1 / g.clone(); + } + + // Close enough? + let (n_f, d_f) = match (<F as NumCast>::from(n), <F as NumCast>::from(d)) { + (Some(n_f), Some(d_f)) => (n_f, d_f), + _ => break, + }; + if (n_f / d_f - val).abs() < max_error { + break; + } + + // Prevent division by ~0 + if f < epsilon { + break; + } + q = f.recip(); + } + + // Overflow + if d1.is_zero() { + return None; + } + + Some(Ratio::new(n1, d1)) +} + +#[cfg(not(feature = "num-bigint"))] +macro_rules! to_primitive_small { + ($($type_name:ty)*) => ($( + impl ToPrimitive for Ratio<$type_name> { + fn to_i64(&self) -> Option<i64> { + self.to_integer().to_i64() + } + + fn to_i128(&self) -> Option<i128> { + self.to_integer().to_i128() + } + + fn to_u64(&self) -> Option<u64> { + self.to_integer().to_u64() + } + + fn to_u128(&self) -> Option<u128> { + self.to_integer().to_u128() + } + + fn to_f64(&self) -> Option<f64> { + let float = self.numer.to_f64().unwrap() / self.denom.to_f64().unwrap(); + if float.is_nan() { + None + } else { + Some(float) + } + } + } + )*) +} + +#[cfg(not(feature = "num-bigint"))] +to_primitive_small!(u8 i8 u16 i16 u32 i32); + +#[cfg(all(target_pointer_width = "32", not(feature = "num-bigint")))] +to_primitive_small!(usize isize); + +#[cfg(not(feature = "num-bigint"))] +macro_rules! to_primitive_64 { + ($($type_name:ty)*) => ($( + impl ToPrimitive for Ratio<$type_name> { + fn to_i64(&self) -> Option<i64> { + self.to_integer().to_i64() + } + + fn to_i128(&self) -> Option<i128> { + self.to_integer().to_i128() + } + + fn to_u64(&self) -> Option<u64> { + self.to_integer().to_u64() + } + + fn to_u128(&self) -> Option<u128> { + self.to_integer().to_u128() + } + + fn to_f64(&self) -> Option<f64> { + let float = ratio_to_f64( + self.numer as i128, + self.denom as i128 + ); + if float.is_nan() { + None + } else { + Some(float) + } + } + } + )*) +} + +#[cfg(not(feature = "num-bigint"))] +to_primitive_64!(u64 i64); + +#[cfg(all(target_pointer_width = "64", not(feature = "num-bigint")))] +to_primitive_64!(usize isize); + +#[cfg(feature = "num-bigint")] +impl<T: Clone + Integer + ToPrimitive + ToBigInt> ToPrimitive for Ratio<T> { + fn to_i64(&self) -> Option<i64> { + self.to_integer().to_i64() + } + + fn to_i128(&self) -> Option<i128> { + self.to_integer().to_i128() + } + + fn to_u64(&self) -> Option<u64> { + self.to_integer().to_u64() + } + + fn to_u128(&self) -> Option<u128> { + self.to_integer().to_u128() + } + + fn to_f64(&self) -> Option<f64> { + let float = match (self.numer.to_i64(), self.denom.to_i64()) { + (Some(numer), Some(denom)) => ratio_to_f64( + <i128 as From<_>>::from(numer), + <i128 as From<_>>::from(denom), + ), + _ => { + let numer: BigInt = self.numer.to_bigint()?; + let denom: BigInt = self.denom.to_bigint()?; + ratio_to_f64(numer, denom) + } + }; + if float.is_nan() { + None + } else { + Some(float) + } + } +} + +trait Bits { + fn bits(&self) -> u64; +} + +#[cfg(feature = "num-bigint")] +impl Bits for BigInt { + fn bits(&self) -> u64 { + self.bits() + } +} + +impl Bits for i128 { + fn bits(&self) -> u64 { + (128 - self.wrapping_abs().leading_zeros()).into() + } +} + +/// Converts a ratio of `T` to an f64. +/// +/// In addition to stated trait bounds, `T` must be able to hold numbers 56 bits larger than +/// the largest of `numer` and `denom`. This is automatically true if `T` is `BigInt`. +fn ratio_to_f64<T: Bits + Clone + Integer + Signed + ShlAssign<usize> + ToPrimitive>( + numer: T, + denom: T, +) -> f64 { + use core::f64::{INFINITY, MANTISSA_DIGITS, MAX_EXP, MIN_EXP, RADIX}; + + assert_eq!( + RADIX, 2, + "only floating point implementations with radix 2 are supported" + ); + + // Inclusive upper and lower bounds to the range of exactly-representable ints in an f64. + const MAX_EXACT_INT: i64 = 1i64 << MANTISSA_DIGITS; + const MIN_EXACT_INT: i64 = -MAX_EXACT_INT; + + let flo_sign = numer.signum().to_f64().unwrap() / denom.signum().to_f64().unwrap(); + if !flo_sign.is_normal() { + return flo_sign; + } + + // Fast track: both sides can losslessly be converted to f64s. In this case, letting the + // FPU do the job is faster and easier. In any other case, converting to f64s may lead + // to an inexact result: https://stackoverflow.com/questions/56641441/. + if let (Some(n), Some(d)) = (numer.to_i64(), denom.to_i64()) { + if MIN_EXACT_INT <= n && n <= MAX_EXACT_INT && MIN_EXACT_INT <= d && d <= MAX_EXACT_INT { + return n.to_f64().unwrap() / d.to_f64().unwrap(); + } + } + + // Otherwise, the goal is to obtain a quotient with at least 55 bits. 53 of these bits will + // be used as the mantissa of the resulting float, and the remaining two are for rounding. + // There's an error of up to 1 on the number of resulting bits, so we may get either 55 or + // 56 bits. + let mut numer = numer.abs(); + let mut denom = denom.abs(); + let (is_diff_positive, absolute_diff) = match numer.bits().checked_sub(denom.bits()) { + Some(diff) => (true, diff), + None => (false, denom.bits() - numer.bits()), + }; + + // Filter out overflows and underflows. After this step, the signed difference fits in an + // isize. + if is_diff_positive && absolute_diff > MAX_EXP as u64 { + return INFINITY * flo_sign; + } + if !is_diff_positive && absolute_diff > -MIN_EXP as u64 + MANTISSA_DIGITS as u64 + 1 { + return 0.0 * flo_sign; + } + let diff = if is_diff_positive { + absolute_diff.to_isize().unwrap() + } else { + -absolute_diff.to_isize().unwrap() + }; + + // Shift is chosen so that the quotient will have 55 or 56 bits. The exception is if the + // quotient is going to be subnormal, in which case it may have fewer bits. + let shift: isize = diff.max(MIN_EXP as isize) - MANTISSA_DIGITS as isize - 2; + if shift >= 0 { + denom <<= shift as usize + } else { + numer <<= -shift as usize + }; + + let (quotient, remainder) = numer.div_rem(&denom); + + // This is guaranteed to fit since we've set up quotient to be at most 56 bits. + let mut quotient = quotient.to_u64().unwrap(); + let n_rounding_bits = { + let quotient_bits = 64 - quotient.leading_zeros() as isize; + let subnormal_bits = MIN_EXP as isize - shift; + quotient_bits.max(subnormal_bits) - MANTISSA_DIGITS as isize + } as usize; + debug_assert!(n_rounding_bits == 2 || n_rounding_bits == 3); + let rounding_bit_mask = (1u64 << n_rounding_bits) - 1; + + // Round to 53 bits with round-to-even. For rounding, we need to take into account both + // our rounding bits and the division's remainder. + let ls_bit = quotient & (1u64 << n_rounding_bits) != 0; + let ms_rounding_bit = quotient & (1u64 << (n_rounding_bits - 1)) != 0; + let ls_rounding_bits = quotient & (rounding_bit_mask >> 1) != 0; + if ms_rounding_bit && (ls_bit || ls_rounding_bits || !remainder.is_zero()) { + quotient += 1u64 << n_rounding_bits; + } + quotient &= !rounding_bit_mask; + + // The quotient is guaranteed to be exactly representable as it's now 53 bits + 2 or 3 + // trailing zeros, so there is no risk of a rounding error here. + let q_float = quotient as f64 * flo_sign; + ldexp(q_float, shift as i32) +} + +/// Multiply `x` by 2 to the power of `exp`. Returns an accurate result even if `2^exp` is not +/// representable. +fn ldexp(x: f64, exp: i32) -> f64 { + use core::f64::{INFINITY, MANTISSA_DIGITS, MAX_EXP, RADIX}; + + assert_eq!( + RADIX, 2, + "only floating point implementations with radix 2 are supported" + ); + + const EXPONENT_MASK: u64 = 0x7ff << 52; + const MAX_UNSIGNED_EXPONENT: i32 = 0x7fe; + const MIN_SUBNORMAL_POWER: i32 = MANTISSA_DIGITS as i32; + + if x.is_zero() || x.is_infinite() || x.is_nan() { + return x; + } + + // Filter out obvious over / underflows to make sure the resulting exponent fits in an isize. + if exp > 3 * MAX_EXP { + return INFINITY * x.signum(); + } else if exp < -3 * MAX_EXP { + return 0.0 * x.signum(); + } + + // curr_exp is the x's *biased* exponent, and is in the [-54, MAX_UNSIGNED_EXPONENT] range. + let (bits, curr_exp) = if !x.is_normal() { + // If x is subnormal, we make it normal by multiplying by 2^53. This causes no loss of + // precision or rounding. + let normal_x = x * 2f64.powi(MIN_SUBNORMAL_POWER); + let bits = normal_x.to_bits(); + // This cast is safe because the exponent is at most 0x7fe, which fits in an i32. + ( + bits, + ((bits & EXPONENT_MASK) >> 52) as i32 - MIN_SUBNORMAL_POWER, + ) + } else { + let bits = x.to_bits(); + let curr_exp = (bits & EXPONENT_MASK) >> 52; + // This cast is safe because the exponent is at most 0x7fe, which fits in an i32. + (bits, curr_exp as i32) + }; + + // The addition can't overflow because exponent is between 0 and 0x7fe, and exp is between + // -2*MAX_EXP and 2*MAX_EXP. + let new_exp = curr_exp + exp; + + if new_exp > MAX_UNSIGNED_EXPONENT { + INFINITY * x.signum() + } else if new_exp > 0 { + // Normal case: exponent is not too large nor subnormal. + let new_bits = (bits & !EXPONENT_MASK) | ((new_exp as u64) << 52); + f64::from_bits(new_bits) + } else if new_exp >= -(MANTISSA_DIGITS as i32) { + // Result is subnormal but may not be zero. + // In this case, we increase the exponent by 54 to make it normal, then multiply the end + // result by 2^-53. This results in a single multiplication with no prior rounding error, + // so there is no risk of double rounding. + let new_exp = new_exp + MIN_SUBNORMAL_POWER; + debug_assert!(new_exp >= 0); + let new_bits = (bits & !EXPONENT_MASK) | ((new_exp as u64) << 52); + f64::from_bits(new_bits) * 2f64.powi(-MIN_SUBNORMAL_POWER) + } else { + // Result is zero. + return 0.0 * x.signum(); + } +} + +#[cfg(test)] +#[cfg(feature = "std")] +fn hash<T: Hash>(x: &T) -> u64 { + use std::collections::hash_map::RandomState; + use std::hash::BuildHasher; + let mut hasher = <RandomState as BuildHasher>::Hasher::new(); + x.hash(&mut hasher); + hasher.finish() +} + +#[cfg(test)] +mod test { + use super::ldexp; + #[cfg(all(feature = "num-bigint"))] + use super::BigInt; + #[cfg(feature = "num-bigint")] + use super::BigRational; + use super::{Ratio, Rational64}; + + use core::f64; + use core::i32; + use core::i64; + use core::str::FromStr; + use num_integer::Integer; + use num_traits::ToPrimitive; + use num_traits::{FromPrimitive, One, Pow, Signed, Zero}; + + pub const _0: Rational64 = Ratio { numer: 0, denom: 1 }; + pub const _1: Rational64 = Ratio { numer: 1, denom: 1 }; + pub const _2: Rational64 = Ratio { numer: 2, denom: 1 }; + pub const _NEG2: Rational64 = Ratio { + numer: -2, + denom: 1, + }; + pub const _8: Rational64 = Ratio { numer: 8, denom: 1 }; + pub const _15: Rational64 = Ratio { + numer: 15, + denom: 1, + }; + pub const _16: Rational64 = Ratio { + numer: 16, + denom: 1, + }; + + pub const _1_2: Rational64 = Ratio { numer: 1, denom: 2 }; + pub const _1_8: Rational64 = Ratio { numer: 1, denom: 8 }; + pub const _1_15: Rational64 = Ratio { + numer: 1, + denom: 15, + }; + pub const _1_16: Rational64 = Ratio { + numer: 1, + denom: 16, + }; + pub const _3_2: Rational64 = Ratio { numer: 3, denom: 2 }; + pub const _5_2: Rational64 = Ratio { numer: 5, denom: 2 }; + pub const _NEG1_2: Rational64 = Ratio { + numer: -1, + denom: 2, + }; + pub const _1_NEG2: Rational64 = Ratio { + numer: 1, + denom: -2, + }; + pub const _NEG1_NEG2: Rational64 = Ratio { + numer: -1, + denom: -2, + }; + pub const _1_3: Rational64 = Ratio { numer: 1, denom: 3 }; + pub const _NEG1_3: Rational64 = Ratio { + numer: -1, + denom: 3, + }; + pub const _2_3: Rational64 = Ratio { numer: 2, denom: 3 }; + pub const _NEG2_3: Rational64 = Ratio { + numer: -2, + denom: 3, + }; + pub const _MIN: Rational64 = Ratio { + numer: i64::MIN, + denom: 1, + }; + pub const _MIN_P1: Rational64 = Ratio { + numer: i64::MIN + 1, + denom: 1, + }; + pub const _MAX: Rational64 = Ratio { + numer: i64::MAX, + denom: 1, + }; + pub const _MAX_M1: Rational64 = Ratio { + numer: i64::MAX - 1, + denom: 1, + }; + pub const _BILLION: Rational64 = Ratio { + numer: 1_000_000_000, + denom: 1, + }; + + #[cfg(feature = "num-bigint")] + pub fn to_big(n: Rational64) -> BigRational { + Ratio::new( + FromPrimitive::from_i64(n.numer).unwrap(), + FromPrimitive::from_i64(n.denom).unwrap(), + ) + } + #[cfg(not(feature = "num-bigint"))] + pub fn to_big(n: Rational64) -> Rational64 { + Ratio::new( + FromPrimitive::from_i64(n.numer).unwrap(), + FromPrimitive::from_i64(n.denom).unwrap(), + ) + } + + #[test] + fn test_test_constants() { + // check our constants are what Ratio::new etc. would make. + assert_eq!(_0, Zero::zero()); + assert_eq!(_1, One::one()); + assert_eq!(_2, Ratio::from_integer(2)); + assert_eq!(_1_2, Ratio::new(1, 2)); + assert_eq!(_3_2, Ratio::new(3, 2)); + assert_eq!(_NEG1_2, Ratio::new(-1, 2)); + assert_eq!(_2, From::from(2)); + } + + #[test] + fn test_new_reduce() { + assert_eq!(Ratio::new(2, 2), One::one()); + assert_eq!(Ratio::new(0, i32::MIN), Zero::zero()); + assert_eq!(Ratio::new(i32::MIN, i32::MIN), One::one()); + } + #[test] + #[should_panic] + fn test_new_zero() { + let _a = Ratio::new(1, 0); + } + + #[test] + fn test_approximate_float() { + assert_eq!(Ratio::from_f32(0.5f32), Some(Ratio::new(1i64, 2))); + assert_eq!(Ratio::from_f64(0.5f64), Some(Ratio::new(1i32, 2))); + assert_eq!(Ratio::from_f32(5f32), Some(Ratio::new(5i64, 1))); + assert_eq!(Ratio::from_f64(5f64), Some(Ratio::new(5i32, 1))); + assert_eq!(Ratio::from_f32(29.97f32), Some(Ratio::new(2997i64, 100))); + assert_eq!(Ratio::from_f32(-29.97f32), Some(Ratio::new(-2997i64, 100))); + + assert_eq!(Ratio::<i8>::from_f32(63.5f32), Some(Ratio::new(127i8, 2))); + assert_eq!(Ratio::<i8>::from_f32(126.5f32), Some(Ratio::new(126i8, 1))); + assert_eq!(Ratio::<i8>::from_f32(127.0f32), Some(Ratio::new(127i8, 1))); + assert_eq!(Ratio::<i8>::from_f32(127.5f32), None); + assert_eq!(Ratio::<i8>::from_f32(-63.5f32), Some(Ratio::new(-127i8, 2))); + assert_eq!( + Ratio::<i8>::from_f32(-126.5f32), + Some(Ratio::new(-126i8, 1)) + ); + assert_eq!( + Ratio::<i8>::from_f32(-127.0f32), + Some(Ratio::new(-127i8, 1)) + ); + assert_eq!(Ratio::<i8>::from_f32(-127.5f32), None); + + assert_eq!(Ratio::<u8>::from_f32(-127f32), None); + assert_eq!(Ratio::<u8>::from_f32(127f32), Some(Ratio::new(127u8, 1))); + assert_eq!(Ratio::<u8>::from_f32(127.5f32), Some(Ratio::new(255u8, 2))); + assert_eq!(Ratio::<u8>::from_f32(256f32), None); + + assert_eq!(Ratio::<i64>::from_f64(-10e200), None); + assert_eq!(Ratio::<i64>::from_f64(10e200), None); + assert_eq!(Ratio::<i64>::from_f64(f64::INFINITY), None); + assert_eq!(Ratio::<i64>::from_f64(f64::NEG_INFINITY), None); + assert_eq!(Ratio::<i64>::from_f64(f64::NAN), None); + assert_eq!( + Ratio::<i64>::from_f64(f64::EPSILON), + Some(Ratio::new(1, 4503599627370496)) + ); + assert_eq!(Ratio::<i64>::from_f64(0.0), Some(Ratio::new(0, 1))); + assert_eq!(Ratio::<i64>::from_f64(-0.0), Some(Ratio::new(0, 1))); + } + + #[test] + #[allow(clippy::eq_op)] + fn test_cmp() { + assert!(_0 == _0 && _1 == _1); + assert!(_0 != _1 && _1 != _0); + assert!(_0 < _1 && !(_1 < _0)); + assert!(_1 > _0 && !(_0 > _1)); + + assert!(_0 <= _0 && _1 <= _1); + assert!(_0 <= _1 && !(_1 <= _0)); + + assert!(_0 >= _0 && _1 >= _1); + assert!(_1 >= _0 && !(_0 >= _1)); + + let _0_2: Rational64 = Ratio::new_raw(0, 2); + assert_eq!(_0, _0_2); + } + + #[test] + fn test_cmp_overflow() { + use core::cmp::Ordering; + + // issue #7 example: + let big = Ratio::new(128u8, 1); + let small = big.recip(); + assert!(big > small); + + // try a few that are closer together + // (some matching numer, some matching denom, some neither) + let ratios = [ + Ratio::new(125_i8, 127_i8), + Ratio::new(63_i8, 64_i8), + Ratio::new(124_i8, 125_i8), + Ratio::new(125_i8, 126_i8), + Ratio::new(126_i8, 127_i8), + Ratio::new(127_i8, 126_i8), + ]; + + fn check_cmp(a: Ratio<i8>, b: Ratio<i8>, ord: Ordering) { + #[cfg(feature = "std")] + println!("comparing {} and {}", a, b); + assert_eq!(a.cmp(&b), ord); + assert_eq!(b.cmp(&a), ord.reverse()); + } + + for (i, &a) in ratios.iter().enumerate() { + check_cmp(a, a, Ordering::Equal); + check_cmp(-a, a, Ordering::Less); + for &b in &ratios[i + 1..] { + check_cmp(a, b, Ordering::Less); + check_cmp(-a, -b, Ordering::Greater); + check_cmp(a.recip(), b.recip(), Ordering::Greater); + check_cmp(-a.recip(), -b.recip(), Ordering::Less); + } + } + } + + #[test] + fn test_to_integer() { + assert_eq!(_0.to_integer(), 0); + assert_eq!(_1.to_integer(), 1); + assert_eq!(_2.to_integer(), 2); + assert_eq!(_1_2.to_integer(), 0); + assert_eq!(_3_2.to_integer(), 1); + assert_eq!(_NEG1_2.to_integer(), 0); + } + + #[test] + fn test_numer() { + assert_eq!(_0.numer(), &0); + assert_eq!(_1.numer(), &1); + assert_eq!(_2.numer(), &2); + assert_eq!(_1_2.numer(), &1); + assert_eq!(_3_2.numer(), &3); + assert_eq!(_NEG1_2.numer(), &(-1)); + } + #[test] + fn test_denom() { + assert_eq!(_0.denom(), &1); + assert_eq!(_1.denom(), &1); + assert_eq!(_2.denom(), &1); + assert_eq!(_1_2.denom(), &2); + assert_eq!(_3_2.denom(), &2); + assert_eq!(_NEG1_2.denom(), &2); + } + + #[test] + fn test_is_integer() { + assert!(_0.is_integer()); + assert!(_1.is_integer()); + assert!(_2.is_integer()); + assert!(!_1_2.is_integer()); + assert!(!_3_2.is_integer()); + assert!(!_NEG1_2.is_integer()); + } + + #[cfg(not(feature = "std"))] + use core::fmt::{self, Write}; + #[cfg(not(feature = "std"))] + #[derive(Debug)] + struct NoStdTester { + cursor: usize, + buf: [u8; NoStdTester::BUF_SIZE], + } + + #[cfg(not(feature = "std"))] + impl NoStdTester { + fn new() -> NoStdTester { + NoStdTester { + buf: [0; Self::BUF_SIZE], + cursor: 0, + } + } + + fn clear(&mut self) { + self.buf = [0; Self::BUF_SIZE]; + self.cursor = 0; + } + + const WRITE_ERR: &'static str = "Formatted output too long"; + const BUF_SIZE: usize = 32; + } + + #[cfg(not(feature = "std"))] + impl Write for NoStdTester { + fn write_str(&mut self, s: &str) -> fmt::Result { + for byte in s.bytes() { + self.buf[self.cursor] = byte; + self.cursor += 1; + if self.cursor >= self.buf.len() { + return Err(fmt::Error {}); + } + } + Ok(()) + } + } + + #[cfg(not(feature = "std"))] + impl PartialEq<str> for NoStdTester { + fn eq(&self, other: &str) -> bool { + let other = other.as_bytes(); + for index in 0..self.cursor { + if self.buf.get(index) != other.get(index) { + return false; + } + } + true + } + } + + macro_rules! assert_fmt_eq { + ($fmt_args:expr, $string:expr) => { + #[cfg(not(feature = "std"))] + { + let mut tester = NoStdTester::new(); + write!(tester, "{}", $fmt_args).expect(NoStdTester::WRITE_ERR); + assert_eq!(tester, *$string); + tester.clear(); + } + #[cfg(feature = "std")] + { + assert_eq!(std::fmt::format($fmt_args), $string); + } + }; + } + + #[test] + fn test_show() { + // Test: + // :b :o :x, :X, :? + // alternate or not (#) + // positive and negative + // padding + // does not test precision (i.e. truncation) + assert_fmt_eq!(format_args!("{}", _2), "2"); + assert_fmt_eq!(format_args!("{:+}", _2), "+2"); + assert_fmt_eq!(format_args!("{:-}", _2), "2"); + assert_fmt_eq!(format_args!("{}", _1_2), "1/2"); + assert_fmt_eq!(format_args!("{}", -_1_2), "-1/2"); // test negatives + assert_fmt_eq!(format_args!("{}", _0), "0"); + assert_fmt_eq!(format_args!("{}", -_2), "-2"); + assert_fmt_eq!(format_args!("{:+}", -_2), "-2"); + assert_fmt_eq!(format_args!("{:b}", _2), "10"); + assert_fmt_eq!(format_args!("{:#b}", _2), "0b10"); + assert_fmt_eq!(format_args!("{:b}", _1_2), "1/10"); + assert_fmt_eq!(format_args!("{:+b}", _1_2), "+1/10"); + assert_fmt_eq!(format_args!("{:-b}", _1_2), "1/10"); + assert_fmt_eq!(format_args!("{:b}", _0), "0"); + assert_fmt_eq!(format_args!("{:#b}", _1_2), "0b1/0b10"); + // no std does not support padding + #[cfg(feature = "std")] + assert_eq!(&format!("{:010b}", _1_2), "0000001/10"); + #[cfg(feature = "std")] + assert_eq!(&format!("{:#010b}", _1_2), "0b001/0b10"); + let half_i8: Ratio<i8> = Ratio::new(1_i8, 2_i8); + assert_fmt_eq!(format_args!("{:b}", -half_i8), "11111111/10"); + assert_fmt_eq!(format_args!("{:#b}", -half_i8), "0b11111111/0b10"); + #[cfg(feature = "std")] + assert_eq!(&format!("{:05}", Ratio::new(-1_i8, 1_i8)), "-0001"); + + assert_fmt_eq!(format_args!("{:o}", _8), "10"); + assert_fmt_eq!(format_args!("{:o}", _1_8), "1/10"); + assert_fmt_eq!(format_args!("{:o}", _0), "0"); + assert_fmt_eq!(format_args!("{:#o}", _1_8), "0o1/0o10"); + #[cfg(feature = "std")] + assert_eq!(&format!("{:010o}", _1_8), "0000001/10"); + #[cfg(feature = "std")] + assert_eq!(&format!("{:#010o}", _1_8), "0o001/0o10"); + assert_fmt_eq!(format_args!("{:o}", -half_i8), "377/2"); + assert_fmt_eq!(format_args!("{:#o}", -half_i8), "0o377/0o2"); + + assert_fmt_eq!(format_args!("{:x}", _16), "10"); + assert_fmt_eq!(format_args!("{:x}", _15), "f"); + assert_fmt_eq!(format_args!("{:x}", _1_16), "1/10"); + assert_fmt_eq!(format_args!("{:x}", _1_15), "1/f"); + assert_fmt_eq!(format_args!("{:x}", _0), "0"); + assert_fmt_eq!(format_args!("{:#x}", _1_16), "0x1/0x10"); + #[cfg(feature = "std")] + assert_eq!(&format!("{:010x}", _1_16), "0000001/10"); + #[cfg(feature = "std")] + assert_eq!(&format!("{:#010x}", _1_16), "0x001/0x10"); + assert_fmt_eq!(format_args!("{:x}", -half_i8), "ff/2"); + assert_fmt_eq!(format_args!("{:#x}", -half_i8), "0xff/0x2"); + + assert_fmt_eq!(format_args!("{:X}", _16), "10"); + assert_fmt_eq!(format_args!("{:X}", _15), "F"); + assert_fmt_eq!(format_args!("{:X}", _1_16), "1/10"); + assert_fmt_eq!(format_args!("{:X}", _1_15), "1/F"); + assert_fmt_eq!(format_args!("{:X}", _0), "0"); + assert_fmt_eq!(format_args!("{:#X}", _1_16), "0x1/0x10"); + #[cfg(feature = "std")] + assert_eq!(format!("{:010X}", _1_16), "0000001/10"); + #[cfg(feature = "std")] + assert_eq!(format!("{:#010X}", _1_16), "0x001/0x10"); + assert_fmt_eq!(format_args!("{:X}", -half_i8), "FF/2"); + assert_fmt_eq!(format_args!("{:#X}", -half_i8), "0xFF/0x2"); + + #[cfg(has_int_exp_fmt)] + { + assert_fmt_eq!(format_args!("{:e}", -_2), "-2e0"); + assert_fmt_eq!(format_args!("{:#e}", -_2), "-2e0"); + assert_fmt_eq!(format_args!("{:+e}", -_2), "-2e0"); + assert_fmt_eq!(format_args!("{:e}", _BILLION), "1e9"); + assert_fmt_eq!(format_args!("{:+e}", _BILLION), "+1e9"); + assert_fmt_eq!(format_args!("{:e}", _BILLION.recip()), "1e0/1e9"); + assert_fmt_eq!(format_args!("{:+e}", _BILLION.recip()), "+1e0/1e9"); + + assert_fmt_eq!(format_args!("{:E}", -_2), "-2E0"); + assert_fmt_eq!(format_args!("{:#E}", -_2), "-2E0"); + assert_fmt_eq!(format_args!("{:+E}", -_2), "-2E0"); + assert_fmt_eq!(format_args!("{:E}", _BILLION), "1E9"); + assert_fmt_eq!(format_args!("{:+E}", _BILLION), "+1E9"); + assert_fmt_eq!(format_args!("{:E}", _BILLION.recip()), "1E0/1E9"); + assert_fmt_eq!(format_args!("{:+E}", _BILLION.recip()), "+1E0/1E9"); + } + } + + mod arith { + use super::super::{Ratio, Rational64}; + use super::{to_big, _0, _1, _1_2, _2, _3_2, _5_2, _MAX, _MAX_M1, _MIN, _MIN_P1, _NEG1_2}; + use core::fmt::Debug; + use num_integer::Integer; + use num_traits::{Bounded, CheckedAdd, CheckedDiv, CheckedMul, CheckedSub, NumAssign}; + + #[test] + fn test_add() { + fn test(a: Rational64, b: Rational64, c: Rational64) { + assert_eq!(a + b, c); + assert_eq!( + { + let mut x = a; + x += b; + x + }, + c + ); + assert_eq!(to_big(a) + to_big(b), to_big(c)); + assert_eq!(a.checked_add(&b), Some(c)); + assert_eq!(to_big(a).checked_add(&to_big(b)), Some(to_big(c))); + } + fn test_assign(a: Rational64, b: i64, c: Rational64) { + assert_eq!(a + b, c); + assert_eq!( + { + let mut x = a; + x += b; + x + }, + c + ); + } + + test(_1, _1_2, _3_2); + test(_1, _1, _2); + test(_1_2, _3_2, _2); + test(_1_2, _NEG1_2, _0); + test_assign(_1_2, 1, _3_2); + } + + #[test] + fn test_add_overflow() { + // compares Ratio(1, T::max_value()) + Ratio(1, T::max_value()) + // to Ratio(1+1, T::max_value()) for each integer type. + // Previously, this calculation would overflow. + fn test_add_typed_overflow<T>() + where + T: Integer + Bounded + Clone + Debug + NumAssign, + { + let _1_max = Ratio::new(T::one(), T::max_value()); + let _2_max = Ratio::new(T::one() + T::one(), T::max_value()); + assert_eq!(_1_max.clone() + _1_max.clone(), _2_max); + assert_eq!( + { + let mut tmp = _1_max.clone(); + tmp += _1_max; + tmp + }, + _2_max + ); + } + test_add_typed_overflow::<u8>(); + test_add_typed_overflow::<u16>(); + test_add_typed_overflow::<u32>(); + test_add_typed_overflow::<u64>(); + test_add_typed_overflow::<usize>(); + test_add_typed_overflow::<u128>(); + + test_add_typed_overflow::<i8>(); + test_add_typed_overflow::<i16>(); + test_add_typed_overflow::<i32>(); + test_add_typed_overflow::<i64>(); + test_add_typed_overflow::<isize>(); + test_add_typed_overflow::<i128>(); + } + + #[test] + fn test_sub() { + fn test(a: Rational64, b: Rational64, c: Rational64) { + assert_eq!(a - b, c); + assert_eq!( + { + let mut x = a; + x -= b; + x + }, + c + ); + assert_eq!(to_big(a) - to_big(b), to_big(c)); + assert_eq!(a.checked_sub(&b), Some(c)); + assert_eq!(to_big(a).checked_sub(&to_big(b)), Some(to_big(c))); + } + fn test_assign(a: Rational64, b: i64, c: Rational64) { + assert_eq!(a - b, c); + assert_eq!( + { + let mut x = a; + x -= b; + x + }, + c + ); + } + + test(_1, _1_2, _1_2); + test(_3_2, _1_2, _1); + test(_1, _NEG1_2, _3_2); + test_assign(_1_2, 1, _NEG1_2); + } + + #[test] + fn test_sub_overflow() { + // compares Ratio(1, T::max_value()) - Ratio(1, T::max_value()) to T::zero() + // for each integer type. Previously, this calculation would overflow. + fn test_sub_typed_overflow<T>() + where + T: Integer + Bounded + Clone + Debug + NumAssign, + { + let _1_max: Ratio<T> = Ratio::new(T::one(), T::max_value()); + assert!(T::is_zero(&(_1_max.clone() - _1_max.clone()).numer)); + { + let mut tmp: Ratio<T> = _1_max.clone(); + tmp -= _1_max; + assert!(T::is_zero(&tmp.numer)); + } + } + test_sub_typed_overflow::<u8>(); + test_sub_typed_overflow::<u16>(); + test_sub_typed_overflow::<u32>(); + test_sub_typed_overflow::<u64>(); + test_sub_typed_overflow::<usize>(); + test_sub_typed_overflow::<u128>(); + + test_sub_typed_overflow::<i8>(); + test_sub_typed_overflow::<i16>(); + test_sub_typed_overflow::<i32>(); + test_sub_typed_overflow::<i64>(); + test_sub_typed_overflow::<isize>(); + test_sub_typed_overflow::<i128>(); + } + + #[test] + fn test_mul() { + fn test(a: Rational64, b: Rational64, c: Rational64) { + assert_eq!(a * b, c); + assert_eq!( + { + let mut x = a; + x *= b; + x + }, + c + ); + assert_eq!(to_big(a) * to_big(b), to_big(c)); + assert_eq!(a.checked_mul(&b), Some(c)); + assert_eq!(to_big(a).checked_mul(&to_big(b)), Some(to_big(c))); + } + fn test_assign(a: Rational64, b: i64, c: Rational64) { + assert_eq!(a * b, c); + assert_eq!( + { + let mut x = a; + x *= b; + x + }, + c + ); + } + + test(_1, _1_2, _1_2); + test(_1_2, _3_2, Ratio::new(3, 4)); + test(_1_2, _NEG1_2, Ratio::new(-1, 4)); + test_assign(_1_2, 2, _1); + } + + #[test] + fn test_mul_overflow() { + fn test_mul_typed_overflow<T>() + where + T: Integer + Bounded + Clone + Debug + NumAssign + CheckedMul, + { + let two = T::one() + T::one(); + let _3 = T::one() + T::one() + T::one(); + + // 1/big * 2/3 = 1/(max/4*3), where big is max/2 + // make big = max/2, but also divisible by 2 + let big = T::max_value() / two.clone() / two.clone() * two.clone(); + let _1_big: Ratio<T> = Ratio::new(T::one(), big.clone()); + let _2_3: Ratio<T> = Ratio::new(two.clone(), _3.clone()); + assert_eq!(None, big.clone().checked_mul(&_3.clone())); + let expected = Ratio::new(T::one(), big / two.clone() * _3.clone()); + assert_eq!(expected.clone(), _1_big.clone() * _2_3.clone()); + assert_eq!( + Some(expected.clone()), + _1_big.clone().checked_mul(&_2_3.clone()) + ); + assert_eq!(expected, { + let mut tmp = _1_big; + tmp *= _2_3; + tmp + }); + + // big/3 * 3 = big/1 + // make big = max/2, but make it indivisible by 3 + let big = T::max_value() / two / _3.clone() * _3.clone() + T::one(); + assert_eq!(None, big.clone().checked_mul(&_3.clone())); + let big_3 = Ratio::new(big.clone(), _3.clone()); + let expected = Ratio::new(big, T::one()); + assert_eq!(expected, big_3.clone() * _3.clone()); + assert_eq!(expected, { + let mut tmp = big_3; + tmp *= _3; + tmp + }); + } + test_mul_typed_overflow::<u16>(); + test_mul_typed_overflow::<u8>(); + test_mul_typed_overflow::<u32>(); + test_mul_typed_overflow::<u64>(); + test_mul_typed_overflow::<usize>(); + test_mul_typed_overflow::<u128>(); + + test_mul_typed_overflow::<i8>(); + test_mul_typed_overflow::<i16>(); + test_mul_typed_overflow::<i32>(); + test_mul_typed_overflow::<i64>(); + test_mul_typed_overflow::<isize>(); + test_mul_typed_overflow::<i128>(); + } + + #[test] + fn test_div() { + fn test(a: Rational64, b: Rational64, c: Rational64) { + assert_eq!(a / b, c); + assert_eq!( + { + let mut x = a; + x /= b; + x + }, + c + ); + assert_eq!(to_big(a) / to_big(b), to_big(c)); + assert_eq!(a.checked_div(&b), Some(c)); + assert_eq!(to_big(a).checked_div(&to_big(b)), Some(to_big(c))); + } + fn test_assign(a: Rational64, b: i64, c: Rational64) { + assert_eq!(a / b, c); + assert_eq!( + { + let mut x = a; + x /= b; + x + }, + c + ); + } + + test(_1, _1_2, _2); + test(_3_2, _1_2, _1 + _2); + test(_1, _NEG1_2, _NEG1_2 + _NEG1_2 + _NEG1_2 + _NEG1_2); + test_assign(_1, 2, _1_2); + } + + #[test] + fn test_div_overflow() { + fn test_div_typed_overflow<T>() + where + T: Integer + Bounded + Clone + Debug + NumAssign + CheckedMul, + { + let two = T::one() + T::one(); + let _3 = T::one() + T::one() + T::one(); + + // 1/big / 3/2 = 1/(max/4*3), where big is max/2 + // big ~ max/2, and big is divisible by 2 + let big = T::max_value() / two.clone() / two.clone() * two.clone(); + assert_eq!(None, big.clone().checked_mul(&_3.clone())); + let _1_big: Ratio<T> = Ratio::new(T::one(), big.clone()); + let _3_two: Ratio<T> = Ratio::new(_3.clone(), two.clone()); + let expected = Ratio::new(T::one(), big / two.clone() * _3.clone()); + assert_eq!(expected.clone(), _1_big.clone() / _3_two.clone()); + assert_eq!( + Some(expected.clone()), + _1_big.clone().checked_div(&_3_two.clone()) + ); + assert_eq!(expected, { + let mut tmp = _1_big; + tmp /= _3_two; + tmp + }); + + // 3/big / 3 = 1/big where big is max/2 + // big ~ max/2, and big is not divisible by 3 + let big = T::max_value() / two / _3.clone() * _3.clone() + T::one(); + assert_eq!(None, big.clone().checked_mul(&_3.clone())); + let _3_big = Ratio::new(_3.clone(), big.clone()); + let expected = Ratio::new(T::one(), big); + assert_eq!(expected, _3_big.clone() / _3.clone()); + assert_eq!(expected, { + let mut tmp = _3_big; + tmp /= _3; + tmp + }); + } + test_div_typed_overflow::<u8>(); + test_div_typed_overflow::<u16>(); + test_div_typed_overflow::<u32>(); + test_div_typed_overflow::<u64>(); + test_div_typed_overflow::<usize>(); + test_div_typed_overflow::<u128>(); + + test_div_typed_overflow::<i8>(); + test_div_typed_overflow::<i16>(); + test_div_typed_overflow::<i32>(); + test_div_typed_overflow::<i64>(); + test_div_typed_overflow::<isize>(); + test_div_typed_overflow::<i128>(); + } + + #[test] + fn test_rem() { + fn test(a: Rational64, b: Rational64, c: Rational64) { + assert_eq!(a % b, c); + assert_eq!( + { + let mut x = a; + x %= b; + x + }, + c + ); + assert_eq!(to_big(a) % to_big(b), to_big(c)) + } + fn test_assign(a: Rational64, b: i64, c: Rational64) { + assert_eq!(a % b, c); + assert_eq!( + { + let mut x = a; + x %= b; + x + }, + c + ); + } + + test(_3_2, _1, _1_2); + test(_3_2, _1_2, _0); + test(_5_2, _3_2, _1); + test(_2, _NEG1_2, _0); + test(_1_2, _2, _1_2); + test_assign(_3_2, 1, _1_2); + } + + #[test] + fn test_rem_overflow() { + // tests that Ratio(1,2) % Ratio(1, T::max_value()) equals 0 + // for each integer type. Previously, this calculation would overflow. + fn test_rem_typed_overflow<T>() + where + T: Integer + Bounded + Clone + Debug + NumAssign, + { + let two = T::one() + T::one(); + // value near to maximum, but divisible by two + let max_div2 = T::max_value() / two.clone() * two.clone(); + let _1_max: Ratio<T> = Ratio::new(T::one(), max_div2); + let _1_two: Ratio<T> = Ratio::new(T::one(), two); + assert!(T::is_zero(&(_1_two.clone() % _1_max.clone()).numer)); + { + let mut tmp: Ratio<T> = _1_two; + tmp %= _1_max; + assert!(T::is_zero(&tmp.numer)); + } + } + test_rem_typed_overflow::<u8>(); + test_rem_typed_overflow::<u16>(); + test_rem_typed_overflow::<u32>(); + test_rem_typed_overflow::<u64>(); + test_rem_typed_overflow::<usize>(); + test_rem_typed_overflow::<u128>(); + + test_rem_typed_overflow::<i8>(); + test_rem_typed_overflow::<i16>(); + test_rem_typed_overflow::<i32>(); + test_rem_typed_overflow::<i64>(); + test_rem_typed_overflow::<isize>(); + test_rem_typed_overflow::<i128>(); + } + + #[test] + fn test_neg() { + fn test(a: Rational64, b: Rational64) { + assert_eq!(-a, b); + assert_eq!(-to_big(a), to_big(b)) + } + + test(_0, _0); + test(_1_2, _NEG1_2); + test(-_1, _1); + } + #[test] + #[allow(clippy::eq_op)] + fn test_zero() { + assert_eq!(_0 + _0, _0); + assert_eq!(_0 * _0, _0); + assert_eq!(_0 * _1, _0); + assert_eq!(_0 / _NEG1_2, _0); + assert_eq!(_0 - _0, _0); + } + #[test] + #[should_panic] + fn test_div_0() { + let _a = _1 / _0; + } + + #[test] + fn test_checked_failures() { + let big = Ratio::new(128u8, 1); + let small = Ratio::new(1, 128u8); + assert_eq!(big.checked_add(&big), None); + assert_eq!(small.checked_sub(&big), None); + assert_eq!(big.checked_mul(&big), None); + assert_eq!(small.checked_div(&big), None); + assert_eq!(_1.checked_div(&_0), None); + } + + #[test] + fn test_checked_zeros() { + assert_eq!(_0.checked_add(&_0), Some(_0)); + assert_eq!(_0.checked_sub(&_0), Some(_0)); + assert_eq!(_0.checked_mul(&_0), Some(_0)); + assert_eq!(_0.checked_div(&_0), None); + } + + #[test] + fn test_checked_min() { + assert_eq!(_MIN.checked_add(&_MIN), None); + assert_eq!(_MIN.checked_sub(&_MIN), Some(_0)); + assert_eq!(_MIN.checked_mul(&_MIN), None); + assert_eq!(_MIN.checked_div(&_MIN), Some(_1)); + assert_eq!(_0.checked_add(&_MIN), Some(_MIN)); + assert_eq!(_0.checked_sub(&_MIN), None); + assert_eq!(_0.checked_mul(&_MIN), Some(_0)); + assert_eq!(_0.checked_div(&_MIN), Some(_0)); + assert_eq!(_1.checked_add(&_MIN), Some(_MIN_P1)); + assert_eq!(_1.checked_sub(&_MIN), None); + assert_eq!(_1.checked_mul(&_MIN), Some(_MIN)); + assert_eq!(_1.checked_div(&_MIN), None); + assert_eq!(_MIN.checked_add(&_0), Some(_MIN)); + assert_eq!(_MIN.checked_sub(&_0), Some(_MIN)); + assert_eq!(_MIN.checked_mul(&_0), Some(_0)); + assert_eq!(_MIN.checked_div(&_0), None); + assert_eq!(_MIN.checked_add(&_1), Some(_MIN_P1)); + assert_eq!(_MIN.checked_sub(&_1), None); + assert_eq!(_MIN.checked_mul(&_1), Some(_MIN)); + assert_eq!(_MIN.checked_div(&_1), Some(_MIN)); + } + + #[test] + fn test_checked_max() { + assert_eq!(_MAX.checked_add(&_MAX), None); + assert_eq!(_MAX.checked_sub(&_MAX), Some(_0)); + assert_eq!(_MAX.checked_mul(&_MAX), None); + assert_eq!(_MAX.checked_div(&_MAX), Some(_1)); + assert_eq!(_0.checked_add(&_MAX), Some(_MAX)); + assert_eq!(_0.checked_sub(&_MAX), Some(_MIN_P1)); + assert_eq!(_0.checked_mul(&_MAX), Some(_0)); + assert_eq!(_0.checked_div(&_MAX), Some(_0)); + assert_eq!(_1.checked_add(&_MAX), None); + assert_eq!(_1.checked_sub(&_MAX), Some(-_MAX_M1)); + assert_eq!(_1.checked_mul(&_MAX), Some(_MAX)); + assert_eq!(_1.checked_div(&_MAX), Some(_MAX.recip())); + assert_eq!(_MAX.checked_add(&_0), Some(_MAX)); + assert_eq!(_MAX.checked_sub(&_0), Some(_MAX)); + assert_eq!(_MAX.checked_mul(&_0), Some(_0)); + assert_eq!(_MAX.checked_div(&_0), None); + assert_eq!(_MAX.checked_add(&_1), None); + assert_eq!(_MAX.checked_sub(&_1), Some(_MAX_M1)); + assert_eq!(_MAX.checked_mul(&_1), Some(_MAX)); + assert_eq!(_MAX.checked_div(&_1), Some(_MAX)); + } + + #[test] + fn test_checked_min_max() { + assert_eq!(_MIN.checked_add(&_MAX), Some(-_1)); + assert_eq!(_MIN.checked_sub(&_MAX), None); + assert_eq!(_MIN.checked_mul(&_MAX), None); + assert_eq!( + _MIN.checked_div(&_MAX), + Some(Ratio::new(_MIN.numer, _MAX.numer)) + ); + assert_eq!(_MAX.checked_add(&_MIN), Some(-_1)); + assert_eq!(_MAX.checked_sub(&_MIN), None); + assert_eq!(_MAX.checked_mul(&_MIN), None); + assert_eq!(_MAX.checked_div(&_MIN), None); + } + } + + #[test] + fn test_round() { + assert_eq!(_1_3.ceil(), _1); + assert_eq!(_1_3.floor(), _0); + assert_eq!(_1_3.round(), _0); + assert_eq!(_1_3.trunc(), _0); + + assert_eq!(_NEG1_3.ceil(), _0); + assert_eq!(_NEG1_3.floor(), -_1); + assert_eq!(_NEG1_3.round(), _0); + assert_eq!(_NEG1_3.trunc(), _0); + + assert_eq!(_2_3.ceil(), _1); + assert_eq!(_2_3.floor(), _0); + assert_eq!(_2_3.round(), _1); + assert_eq!(_2_3.trunc(), _0); + + assert_eq!(_NEG2_3.ceil(), _0); + assert_eq!(_NEG2_3.floor(), -_1); + assert_eq!(_NEG2_3.round(), -_1); + assert_eq!(_NEG2_3.trunc(), _0); + + assert_eq!(_1_2.ceil(), _1); + assert_eq!(_1_2.floor(), _0); + assert_eq!(_1_2.round(), _1); + assert_eq!(_1_2.trunc(), _0); + + assert_eq!(_NEG1_2.ceil(), _0); + assert_eq!(_NEG1_2.floor(), -_1); + assert_eq!(_NEG1_2.round(), -_1); + assert_eq!(_NEG1_2.trunc(), _0); + + assert_eq!(_1.ceil(), _1); + assert_eq!(_1.floor(), _1); + assert_eq!(_1.round(), _1); + assert_eq!(_1.trunc(), _1); + + // Overflow checks + + let _neg1 = Ratio::from_integer(-1); + let _large_rat1 = Ratio::new(i32::MAX, i32::MAX - 1); + let _large_rat2 = Ratio::new(i32::MAX - 1, i32::MAX); + let _large_rat3 = Ratio::new(i32::MIN + 2, i32::MIN + 1); + let _large_rat4 = Ratio::new(i32::MIN + 1, i32::MIN + 2); + let _large_rat5 = Ratio::new(i32::MIN + 2, i32::MAX); + let _large_rat6 = Ratio::new(i32::MAX, i32::MIN + 2); + let _large_rat7 = Ratio::new(1, i32::MIN + 1); + let _large_rat8 = Ratio::new(1, i32::MAX); + + assert_eq!(_large_rat1.round(), One::one()); + assert_eq!(_large_rat2.round(), One::one()); + assert_eq!(_large_rat3.round(), One::one()); + assert_eq!(_large_rat4.round(), One::one()); + assert_eq!(_large_rat5.round(), _neg1); + assert_eq!(_large_rat6.round(), _neg1); + assert_eq!(_large_rat7.round(), Zero::zero()); + assert_eq!(_large_rat8.round(), Zero::zero()); + } + + #[test] + fn test_fract() { + assert_eq!(_1.fract(), _0); + assert_eq!(_NEG1_2.fract(), _NEG1_2); + assert_eq!(_1_2.fract(), _1_2); + assert_eq!(_3_2.fract(), _1_2); + } + + #[test] + fn test_recip() { + assert_eq!(_1 * _1.recip(), _1); + assert_eq!(_2 * _2.recip(), _1); + assert_eq!(_1_2 * _1_2.recip(), _1); + assert_eq!(_3_2 * _3_2.recip(), _1); + assert_eq!(_NEG1_2 * _NEG1_2.recip(), _1); + + assert_eq!(_3_2.recip(), _2_3); + assert_eq!(_NEG1_2.recip(), _NEG2); + assert_eq!(_NEG1_2.recip().denom(), &1); + } + + #[test] + #[should_panic(expected = "division by zero")] + fn test_recip_fail() { + let _a = Ratio::new(0, 1).recip(); + } + + #[test] + fn test_pow() { + fn test(r: Rational64, e: i32, expected: Rational64) { + assert_eq!(r.pow(e), expected); + assert_eq!(Pow::pow(r, e), expected); + assert_eq!(Pow::pow(r, &e), expected); + assert_eq!(Pow::pow(&r, e), expected); + assert_eq!(Pow::pow(&r, &e), expected); + #[cfg(feature = "num-bigint")] + test_big(r, e, expected); + } + + #[cfg(feature = "num-bigint")] + fn test_big(r: Rational64, e: i32, expected: Rational64) { + let r = BigRational::new_raw(r.numer.into(), r.denom.into()); + let expected = BigRational::new_raw(expected.numer.into(), expected.denom.into()); + assert_eq!((&r).pow(e), expected); + assert_eq!(Pow::pow(r.clone(), e), expected); + assert_eq!(Pow::pow(r.clone(), &e), expected); + assert_eq!(Pow::pow(&r, e), expected); + assert_eq!(Pow::pow(&r, &e), expected); + } + + test(_1_2, 2, Ratio::new(1, 4)); + test(_1_2, -2, Ratio::new(4, 1)); + test(_1, 1, _1); + test(_1, i32::MAX, _1); + test(_1, i32::MIN, _1); + test(_NEG1_2, 2, _1_2.pow(2i32)); + test(_NEG1_2, 3, -_1_2.pow(3i32)); + test(_3_2, 0, _1); + test(_3_2, -1, _3_2.recip()); + test(_3_2, 3, Ratio::new(27, 8)); + } + + #[test] + #[cfg(feature = "std")] + fn test_to_from_str() { + use std::string::{String, ToString}; + fn test(r: Rational64, s: String) { + assert_eq!(FromStr::from_str(&s), Ok(r)); + assert_eq!(r.to_string(), s); + } + test(_1, "1".to_string()); + test(_0, "0".to_string()); + test(_1_2, "1/2".to_string()); + test(_3_2, "3/2".to_string()); + test(_2, "2".to_string()); + test(_NEG1_2, "-1/2".to_string()); + } + #[test] + fn test_from_str_fail() { + fn test(s: &str) { + let rational: Result<Rational64, _> = FromStr::from_str(s); + assert!(rational.is_err()); + } + + let xs = ["0 /1", "abc", "", "1/", "--1/2", "3/2/1", "1/0"]; + for &s in xs.iter() { + test(s); + } + } + + #[cfg(feature = "num-bigint")] + #[test] + fn test_from_float() { + use num_traits::float::FloatCore; + fn test<T: FloatCore>(given: T, (numer, denom): (&str, &str)) { + let ratio: BigRational = Ratio::from_float(given).unwrap(); + assert_eq!( + ratio, + Ratio::new( + FromStr::from_str(numer).unwrap(), + FromStr::from_str(denom).unwrap() + ) + ); + } + + // f32 + test(core::f32::consts::PI, ("13176795", "4194304")); + test(2f32.powf(100.), ("1267650600228229401496703205376", "1")); + test( + -(2f32.powf(100.)), + ("-1267650600228229401496703205376", "1"), + ); + test( + 1.0 / 2f32.powf(100.), + ("1", "1267650600228229401496703205376"), + ); + test(684729.48391f32, ("1369459", "2")); + test(-8573.5918555f32, ("-4389679", "512")); + + // f64 + test( + core::f64::consts::PI, + ("884279719003555", "281474976710656"), + ); + test(2f64.powf(100.), ("1267650600228229401496703205376", "1")); + test( + -(2f64.powf(100.)), + ("-1267650600228229401496703205376", "1"), + ); + test(684729.48391f64, ("367611342500051", "536870912")); + test(-8573.5918555f64, ("-4713381968463931", "549755813888")); + test( + 1.0 / 2f64.powf(100.), + ("1", "1267650600228229401496703205376"), + ); + } + + #[cfg(feature = "num-bigint")] + #[test] + fn test_from_float_fail() { + use core::{f32, f64}; + + assert_eq!(Ratio::from_float(f32::NAN), None); + assert_eq!(Ratio::from_float(f32::INFINITY), None); + assert_eq!(Ratio::from_float(f32::NEG_INFINITY), None); + assert_eq!(Ratio::from_float(f64::NAN), None); + assert_eq!(Ratio::from_float(f64::INFINITY), None); + assert_eq!(Ratio::from_float(f64::NEG_INFINITY), None); + } + + #[test] + fn test_signed() { + assert_eq!(_NEG1_2.abs(), _1_2); + assert_eq!(_3_2.abs_sub(&_1_2), _1); + assert_eq!(_1_2.abs_sub(&_3_2), Zero::zero()); + assert_eq!(_1_2.signum(), One::one()); + assert_eq!(_NEG1_2.signum(), -<Ratio<i64>>::one()); + assert_eq!(_0.signum(), Zero::zero()); + assert!(_NEG1_2.is_negative()); + assert!(_1_NEG2.is_negative()); + assert!(!_NEG1_2.is_positive()); + assert!(!_1_NEG2.is_positive()); + assert!(_1_2.is_positive()); + assert!(_NEG1_NEG2.is_positive()); + assert!(!_1_2.is_negative()); + assert!(!_NEG1_NEG2.is_negative()); + assert!(!_0.is_positive()); + assert!(!_0.is_negative()); + } + + #[test] + #[cfg(feature = "std")] + fn test_hash() { + assert!(crate::hash(&_0) != crate::hash(&_1)); + assert!(crate::hash(&_0) != crate::hash(&_3_2)); + + // a == b -> hash(a) == hash(b) + let a = Rational64::new_raw(4, 2); + let b = Rational64::new_raw(6, 3); + assert_eq!(a, b); + assert_eq!(crate::hash(&a), crate::hash(&b)); + + let a = Rational64::new_raw(123456789, 1000); + let b = Rational64::new_raw(123456789 * 5, 5000); + assert_eq!(a, b); + assert_eq!(crate::hash(&a), crate::hash(&b)); + } + + #[test] + fn test_into_pair() { + assert_eq!((0, 1), _0.into()); + assert_eq!((-2, 1), _NEG2.into()); + assert_eq!((1, -2), _1_NEG2.into()); + } + + #[test] + fn test_from_pair() { + assert_eq!(_0, Ratio::from((0, 1))); + assert_eq!(_1, Ratio::from((1, 1))); + assert_eq!(_NEG2, Ratio::from((-2, 1))); + assert_eq!(_1_NEG2, Ratio::from((1, -2))); + } + + #[test] + fn ratio_iter_sum() { + // generic function to assure the iter method can be called + // for any Iterator with Item = Ratio<impl Integer> or Ratio<&impl Integer> + fn iter_sums<T: Integer + Clone>(slice: &[Ratio<T>]) -> [Ratio<T>; 3] { + let mut manual_sum = Ratio::new(T::zero(), T::one()); + for ratio in slice { + manual_sum = manual_sum + ratio; + } + [manual_sum, slice.iter().sum(), slice.iter().cloned().sum()] + } + // collect into array so test works on no_std + let mut nums = [Ratio::new(0, 1); 1000]; + for (i, r) in (0..1000).map(|n| Ratio::new(n, 500)).enumerate() { + nums[i] = r; + } + let sums = iter_sums(&nums[..]); + assert_eq!(sums[0], sums[1]); + assert_eq!(sums[0], sums[2]); + } + + #[test] + fn ratio_iter_product() { + // generic function to assure the iter method can be called + // for any Iterator with Item = Ratio<impl Integer> or Ratio<&impl Integer> + fn iter_products<T: Integer + Clone>(slice: &[Ratio<T>]) -> [Ratio<T>; 3] { + let mut manual_prod = Ratio::new(T::one(), T::one()); + for ratio in slice { + manual_prod = manual_prod * ratio; + } + [ + manual_prod, + slice.iter().product(), + slice.iter().cloned().product(), + ] + } + + // collect into array so test works on no_std + let mut nums = [Ratio::new(0, 1); 1000]; + for (i, r) in (0..1000).map(|n| Ratio::new(n, 500)).enumerate() { + nums[i] = r; + } + let products = iter_products(&nums[..]); + assert_eq!(products[0], products[1]); + assert_eq!(products[0], products[2]); + } + + #[test] + fn test_num_zero() { + let zero = Rational64::zero(); + assert!(zero.is_zero()); + + let mut r = Rational64::new(123, 456); + assert!(!r.is_zero()); + assert_eq!(r + zero, r); + + r.set_zero(); + assert!(r.is_zero()); + } + + #[test] + fn test_num_one() { + let one = Rational64::one(); + assert!(one.is_one()); + + let mut r = Rational64::new(123, 456); + assert!(!r.is_one()); + assert_eq!(r * one, r); + + r.set_one(); + assert!(r.is_one()); + } + + #[test] + fn test_const() { + const N: Ratio<i32> = Ratio::new_raw(123, 456); + const N_NUMER: &i32 = N.numer(); + const N_DENOM: &i32 = N.denom(); + + assert_eq!(N_NUMER, &123); + assert_eq!(N_DENOM, &456); + + let r = N.reduced(); + assert_eq!(r.numer(), &(123 / 3)); + assert_eq!(r.denom(), &(456 / 3)); + } + + #[test] + fn test_ratio_to_i64() { + assert_eq!(5, Rational64::new(70, 14).to_u64().unwrap()); + assert_eq!(-3, Rational64::new(-31, 8).to_i64().unwrap()); + assert_eq!(None, Rational64::new(-31, 8).to_u64()); + } + + #[test] + #[cfg(feature = "num-bigint")] + fn test_ratio_to_i128() { + assert_eq!( + 1i128 << 70, + Ratio::<i128>::new(1i128 << 77, 1i128 << 7) + .to_i128() + .unwrap() + ); + } + + #[test] + #[cfg(feature = "num-bigint")] + fn test_big_ratio_to_f64() { + assert_eq!( + BigRational::new( + "1234567890987654321234567890987654321234567890" + .parse() + .unwrap(), + "3".parse().unwrap() + ) + .to_f64(), + Some(411522630329218100000000000000000000000000000f64) + ); + assert_eq!(Ratio::from_float(5e-324).unwrap().to_f64(), Some(5e-324)); + assert_eq!( + // subnormal + BigRational::new(BigInt::one(), BigInt::one() << 1050).to_f64(), + Some(2.0f64.powi(-50).powi(21)) + ); + assert_eq!( + // definite underflow + BigRational::new(BigInt::one(), BigInt::one() << 1100).to_f64(), + Some(0.0) + ); + assert_eq!( + BigRational::from(BigInt::one() << 1050).to_f64(), + Some(core::f64::INFINITY) + ); + assert_eq!( + BigRational::from((-BigInt::one()) << 1050).to_f64(), + Some(core::f64::NEG_INFINITY) + ); + assert_eq!( + BigRational::new( + "1234567890987654321234567890".parse().unwrap(), + "987654321234567890987654321".parse().unwrap() + ) + .to_f64(), + Some(1.2499999893125f64) + ); + assert_eq!( + BigRational::new_raw(BigInt::one(), BigInt::zero()).to_f64(), + Some(core::f64::INFINITY) + ); + assert_eq!( + BigRational::new_raw(-BigInt::one(), BigInt::zero()).to_f64(), + Some(core::f64::NEG_INFINITY) + ); + assert_eq!( + BigRational::new_raw(BigInt::zero(), BigInt::zero()).to_f64(), + None + ); + } + + #[test] + fn test_ratio_to_f64() { + assert_eq!(Ratio::<u8>::new(1, 2).to_f64(), Some(0.5f64)); + assert_eq!(Rational64::new(1, 2).to_f64(), Some(0.5f64)); + assert_eq!(Rational64::new(1, -2).to_f64(), Some(-0.5f64)); + assert_eq!(Rational64::new(0, 2).to_f64(), Some(0.0f64)); + assert_eq!(Rational64::new(0, -2).to_f64(), Some(-0.0f64)); + assert_eq!(Rational64::new((1 << 57) + 1, 1 << 54).to_f64(), Some(8f64)); + assert_eq!( + Rational64::new((1 << 52) + 1, 1 << 52).to_f64(), + Some(1.0000000000000002f64), + ); + assert_eq!( + Rational64::new((1 << 60) + (1 << 8), 1 << 60).to_f64(), + Some(1.0000000000000002f64), + ); + assert_eq!( + Ratio::<i32>::new_raw(1, 0).to_f64(), + Some(core::f64::INFINITY) + ); + assert_eq!( + Ratio::<i32>::new_raw(-1, 0).to_f64(), + Some(core::f64::NEG_INFINITY) + ); + assert_eq!(Ratio::<i32>::new_raw(0, 0).to_f64(), None); + } + + #[test] + fn test_ldexp() { + use core::f64::{INFINITY, MAX_EXP, MIN_EXP, NAN, NEG_INFINITY}; + assert_eq!(ldexp(1.0, 0), 1.0); + assert_eq!(ldexp(1.0, 1), 2.0); + assert_eq!(ldexp(0.0, 1), 0.0); + assert_eq!(ldexp(-0.0, 1), -0.0); + + // Cases where ldexp is equivalent to multiplying by 2^exp because there's no over- or + // underflow. + assert_eq!(ldexp(3.5, 5), 3.5 * 2f64.powi(5)); + assert_eq!(ldexp(1.0, MAX_EXP - 1), 2f64.powi(MAX_EXP - 1)); + assert_eq!(ldexp(2.77, MIN_EXP + 3), 2.77 * 2f64.powi(MIN_EXP + 3)); + + // Case where initial value is subnormal + assert_eq!(ldexp(5e-324, 4), 5e-324 * 2f64.powi(4)); + assert_eq!(ldexp(5e-324, 200), 5e-324 * 2f64.powi(200)); + + // Near underflow (2^exp is too small to represent, but not x*2^exp) + assert_eq!(ldexp(4.0, MIN_EXP - 3), 2f64.powi(MIN_EXP - 1)); + + // Near overflow + assert_eq!(ldexp(0.125, MAX_EXP + 3), 2f64.powi(MAX_EXP)); + + // Overflow and underflow cases + assert_eq!(ldexp(1.0, MIN_EXP - 54), 0.0); + assert_eq!(ldexp(-1.0, MIN_EXP - 54), -0.0); + assert_eq!(ldexp(1.0, MAX_EXP), INFINITY); + assert_eq!(ldexp(-1.0, MAX_EXP), NEG_INFINITY); + + // Special values + assert_eq!(ldexp(INFINITY, 1), INFINITY); + assert_eq!(ldexp(NEG_INFINITY, 1), NEG_INFINITY); + assert!(ldexp(NAN, 1).is_nan()); + } +} diff --git a/vendor/num-rational/src/pow.rs b/vendor/num-rational/src/pow.rs new file mode 100644 index 0000000..3325332 --- /dev/null +++ b/vendor/num-rational/src/pow.rs @@ -0,0 +1,173 @@ +use crate::Ratio; + +use core::cmp; +use num_integer::Integer; +use num_traits::{One, Pow}; + +macro_rules! pow_unsigned_impl { + (@ $exp:ty) => { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: $exp) -> Ratio<T> { + Ratio::new_raw(self.numer.pow(expon), self.denom.pow(expon)) + } + }; + ($exp:ty) => { + impl<T: Clone + Integer + Pow<$exp, Output = T>> Pow<$exp> for Ratio<T> { + pow_unsigned_impl!(@ $exp); + } + impl<'a, T: Clone + Integer> Pow<$exp> for &'a Ratio<T> + where + &'a T: Pow<$exp, Output = T>, + { + pow_unsigned_impl!(@ $exp); + } + impl<'b, T: Clone + Integer + Pow<$exp, Output = T>> Pow<&'b $exp> for Ratio<T> { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: &'b $exp) -> Ratio<T> { + Pow::pow(self, *expon) + } + } + impl<'a, 'b, T: Clone + Integer> Pow<&'b $exp> for &'a Ratio<T> + where + &'a T: Pow<$exp, Output = T>, + { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: &'b $exp) -> Ratio<T> { + Pow::pow(self, *expon) + } + } + }; +} +pow_unsigned_impl!(u8); +pow_unsigned_impl!(u16); +pow_unsigned_impl!(u32); +pow_unsigned_impl!(u64); +pow_unsigned_impl!(u128); +pow_unsigned_impl!(usize); + +macro_rules! pow_signed_impl { + (@ &'b BigInt, BigUint) => { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: &'b BigInt) -> Ratio<T> { + match expon.sign() { + Sign::NoSign => One::one(), + Sign::Minus => { + Pow::pow(self, expon.magnitude()).into_recip() + } + Sign::Plus => Pow::pow(self, expon.magnitude()), + } + } + }; + (@ $exp:ty, $unsigned:ty) => { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: $exp) -> Ratio<T> { + match expon.cmp(&0) { + cmp::Ordering::Equal => One::one(), + cmp::Ordering::Less => { + let expon = expon.wrapping_abs() as $unsigned; + Pow::pow(self, expon).into_recip() + } + cmp::Ordering::Greater => Pow::pow(self, expon as $unsigned), + } + } + }; + ($exp:ty, $unsigned:ty) => { + impl<T: Clone + Integer + Pow<$unsigned, Output = T>> Pow<$exp> for Ratio<T> { + pow_signed_impl!(@ $exp, $unsigned); + } + impl<'a, T: Clone + Integer> Pow<$exp> for &'a Ratio<T> + where + &'a T: Pow<$unsigned, Output = T>, + { + pow_signed_impl!(@ $exp, $unsigned); + } + impl<'b, T: Clone + Integer + Pow<$unsigned, Output = T>> Pow<&'b $exp> for Ratio<T> { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: &'b $exp) -> Ratio<T> { + Pow::pow(self, *expon) + } + } + impl<'a, 'b, T: Clone + Integer> Pow<&'b $exp> for &'a Ratio<T> + where + &'a T: Pow<$unsigned, Output = T>, + { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: &'b $exp) -> Ratio<T> { + Pow::pow(self, *expon) + } + } + }; +} +pow_signed_impl!(i8, u8); +pow_signed_impl!(i16, u16); +pow_signed_impl!(i32, u32); +pow_signed_impl!(i64, u64); +pow_signed_impl!(i128, u128); +pow_signed_impl!(isize, usize); + +#[cfg(feature = "num-bigint")] +mod bigint { + use super::*; + use num_bigint::{BigInt, BigUint, Sign}; + + impl<T: Clone + Integer + for<'b> Pow<&'b BigUint, Output = T>> Pow<BigUint> for Ratio<T> { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: BigUint) -> Ratio<T> { + Pow::pow(self, &expon) + } + } + impl<'a, T: Clone + Integer> Pow<BigUint> for &'a Ratio<T> + where + &'a T: for<'b> Pow<&'b BigUint, Output = T>, + { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: BigUint) -> Ratio<T> { + Pow::pow(self, &expon) + } + } + impl<'b, T: Clone + Integer + Pow<&'b BigUint, Output = T>> Pow<&'b BigUint> for Ratio<T> { + pow_unsigned_impl!(@ &'b BigUint); + } + impl<'a, 'b, T: Clone + Integer> Pow<&'b BigUint> for &'a Ratio<T> + where + &'a T: Pow<&'b BigUint, Output = T>, + { + pow_unsigned_impl!(@ &'b BigUint); + } + + impl<T: Clone + Integer + for<'b> Pow<&'b BigUint, Output = T>> Pow<BigInt> for Ratio<T> { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: BigInt) -> Ratio<T> { + Pow::pow(self, &expon) + } + } + impl<'a, T: Clone + Integer> Pow<BigInt> for &'a Ratio<T> + where + &'a T: for<'b> Pow<&'b BigUint, Output = T>, + { + type Output = Ratio<T>; + #[inline] + fn pow(self, expon: BigInt) -> Ratio<T> { + Pow::pow(self, &expon) + } + } + impl<'b, T: Clone + Integer + Pow<&'b BigUint, Output = T>> Pow<&'b BigInt> for Ratio<T> { + pow_signed_impl!(@ &'b BigInt, BigUint); + } + impl<'a, 'b, T: Clone + Integer> Pow<&'b BigInt> for &'a Ratio<T> + where + &'a T: Pow<&'b BigUint, Output = T>, + { + pow_signed_impl!(@ &'b BigInt, BigUint); + } +} |