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Diffstat (limited to 'vendor/num-traits/src/pow.rs')
| -rw-r--r-- | vendor/num-traits/src/pow.rs | 242 |
1 files changed, 0 insertions, 242 deletions
diff --git a/vendor/num-traits/src/pow.rs b/vendor/num-traits/src/pow.rs deleted file mode 100644 index ef51c95..0000000 --- a/vendor/num-traits/src/pow.rs +++ /dev/null @@ -1,242 +0,0 @@ -use crate::{CheckedMul, One}; -use core::num::Wrapping; -use core::ops::Mul; - -/// Binary operator for raising a value to a power. -pub trait Pow<RHS> { - /// The result after applying the operator. - type Output; - - /// Returns `self` to the power `rhs`. - /// - /// # Examples - /// - /// ``` - /// use num_traits::Pow; - /// assert_eq!(Pow::pow(10u32, 2u32), 100); - /// ``` - fn pow(self, rhs: RHS) -> Self::Output; -} - -macro_rules! pow_impl { - ($t:ty) => { - pow_impl!($t, u8); - pow_impl!($t, usize); - - // FIXME: these should be possible - // pow_impl!($t, u16); - // pow_impl!($t, u32); - // pow_impl!($t, u64); - }; - ($t:ty, $rhs:ty) => { - pow_impl!($t, $rhs, usize, pow); - }; - ($t:ty, $rhs:ty, $desired_rhs:ty, $method:expr) => { - impl Pow<$rhs> for $t { - type Output = $t; - #[inline] - fn pow(self, rhs: $rhs) -> $t { - ($method)(self, <$desired_rhs>::from(rhs)) - } - } - - impl<'a> Pow<&'a $rhs> for $t { - type Output = $t; - #[inline] - fn pow(self, rhs: &'a $rhs) -> $t { - ($method)(self, <$desired_rhs>::from(*rhs)) - } - } - - impl<'a> Pow<$rhs> for &'a $t { - type Output = $t; - #[inline] - fn pow(self, rhs: $rhs) -> $t { - ($method)(*self, <$desired_rhs>::from(rhs)) - } - } - - impl<'a, 'b> Pow<&'a $rhs> for &'b $t { - type Output = $t; - #[inline] - fn pow(self, rhs: &'a $rhs) -> $t { - ($method)(*self, <$desired_rhs>::from(*rhs)) - } - } - }; -} - -pow_impl!(u8, u8, u32, u8::pow); -pow_impl!(u8, u16, u32, u8::pow); -pow_impl!(u8, u32, u32, u8::pow); -pow_impl!(u8, usize); -pow_impl!(i8, u8, u32, i8::pow); -pow_impl!(i8, u16, u32, i8::pow); -pow_impl!(i8, u32, u32, i8::pow); -pow_impl!(i8, usize); -pow_impl!(u16, u8, u32, u16::pow); -pow_impl!(u16, u16, u32, u16::pow); -pow_impl!(u16, u32, u32, u16::pow); -pow_impl!(u16, usize); -pow_impl!(i16, u8, u32, i16::pow); -pow_impl!(i16, u16, u32, i16::pow); -pow_impl!(i16, u32, u32, i16::pow); -pow_impl!(i16, usize); -pow_impl!(u32, u8, u32, u32::pow); -pow_impl!(u32, u16, u32, u32::pow); -pow_impl!(u32, u32, u32, u32::pow); -pow_impl!(u32, usize); -pow_impl!(i32, u8, u32, i32::pow); -pow_impl!(i32, u16, u32, i32::pow); -pow_impl!(i32, u32, u32, i32::pow); -pow_impl!(i32, usize); -pow_impl!(u64, u8, u32, u64::pow); -pow_impl!(u64, u16, u32, u64::pow); -pow_impl!(u64, u32, u32, u64::pow); -pow_impl!(u64, usize); -pow_impl!(i64, u8, u32, i64::pow); -pow_impl!(i64, u16, u32, i64::pow); -pow_impl!(i64, u32, u32, i64::pow); -pow_impl!(i64, usize); - -pow_impl!(u128, u8, u32, u128::pow); -pow_impl!(u128, u16, u32, u128::pow); -pow_impl!(u128, u32, u32, u128::pow); -pow_impl!(u128, usize); - -pow_impl!(i128, u8, u32, i128::pow); -pow_impl!(i128, u16, u32, i128::pow); -pow_impl!(i128, u32, u32, i128::pow); -pow_impl!(i128, usize); - -pow_impl!(usize, u8, u32, usize::pow); -pow_impl!(usize, u16, u32, usize::pow); -pow_impl!(usize, u32, u32, usize::pow); -pow_impl!(usize, usize); -pow_impl!(isize, u8, u32, isize::pow); -pow_impl!(isize, u16, u32, isize::pow); -pow_impl!(isize, u32, u32, isize::pow); -pow_impl!(isize, usize); -pow_impl!(Wrapping<u8>); -pow_impl!(Wrapping<i8>); -pow_impl!(Wrapping<u16>); -pow_impl!(Wrapping<i16>); -pow_impl!(Wrapping<u32>); -pow_impl!(Wrapping<i32>); -pow_impl!(Wrapping<u64>); -pow_impl!(Wrapping<i64>); -pow_impl!(Wrapping<u128>); -pow_impl!(Wrapping<i128>); -pow_impl!(Wrapping<usize>); -pow_impl!(Wrapping<isize>); - -// FIXME: these should be possible -// pow_impl!(u8, u64); -// pow_impl!(i16, u64); -// pow_impl!(i8, u64); -// pow_impl!(u16, u64); -// pow_impl!(u32, u64); -// pow_impl!(i32, u64); -// pow_impl!(u64, u64); -// pow_impl!(i64, u64); -// pow_impl!(usize, u64); -// pow_impl!(isize, u64); - -#[cfg(any(feature = "std", feature = "libm"))] -mod float_impls { - use super::Pow; - use crate::Float; - - pow_impl!(f32, i8, i32, <f32 as Float>::powi); - pow_impl!(f32, u8, i32, <f32 as Float>::powi); - pow_impl!(f32, i16, i32, <f32 as Float>::powi); - pow_impl!(f32, u16, i32, <f32 as Float>::powi); - pow_impl!(f32, i32, i32, <f32 as Float>::powi); - pow_impl!(f64, i8, i32, <f64 as Float>::powi); - pow_impl!(f64, u8, i32, <f64 as Float>::powi); - pow_impl!(f64, i16, i32, <f64 as Float>::powi); - pow_impl!(f64, u16, i32, <f64 as Float>::powi); - pow_impl!(f64, i32, i32, <f64 as Float>::powi); - pow_impl!(f32, f32, f32, <f32 as Float>::powf); - pow_impl!(f64, f32, f64, <f64 as Float>::powf); - pow_impl!(f64, f64, f64, <f64 as Float>::powf); -} - -/// Raises a value to the power of exp, using exponentiation by squaring. -/// -/// Note that `0⁰` (`pow(0, 0)`) returns `1`. Mathematically this is undefined. -/// -/// # Example -/// -/// ```rust -/// use num_traits::pow; -/// -/// assert_eq!(pow(2i8, 4), 16); -/// assert_eq!(pow(6u8, 3), 216); -/// assert_eq!(pow(0u8, 0), 1); // Be aware if this case affects you -/// ``` -#[inline] -pub fn pow<T: Clone + One + Mul<T, Output = T>>(mut base: T, mut exp: usize) -> T { - if exp == 0 { - return T::one(); - } - - while exp & 1 == 0 { - base = base.clone() * base; - exp >>= 1; - } - if exp == 1 { - return base; - } - - let mut acc = base.clone(); - while exp > 1 { - exp >>= 1; - base = base.clone() * base; - if exp & 1 == 1 { - acc = acc * base.clone(); - } - } - acc -} - -/// Raises a value to the power of exp, returning `None` if an overflow occurred. -/// -/// Note that `0⁰` (`checked_pow(0, 0)`) returns `Some(1)`. Mathematically this is undefined. -/// -/// Otherwise same as the `pow` function. -/// -/// # Example -/// -/// ```rust -/// use num_traits::checked_pow; -/// -/// assert_eq!(checked_pow(2i8, 4), Some(16)); -/// assert_eq!(checked_pow(7i8, 8), None); -/// assert_eq!(checked_pow(7u32, 8), Some(5_764_801)); -/// assert_eq!(checked_pow(0u32, 0), Some(1)); // Be aware if this case affect you -/// ``` -#[inline] -pub fn checked_pow<T: Clone + One + CheckedMul>(mut base: T, mut exp: usize) -> Option<T> { - if exp == 0 { - return Some(T::one()); - } - - while exp & 1 == 0 { - base = base.checked_mul(&base)?; - exp >>= 1; - } - if exp == 1 { - return Some(base); - } - - let mut acc = base.clone(); - while exp > 1 { - exp >>= 1; - base = base.checked_mul(&base)?; - if exp & 1 == 1 { - acc = acc.checked_mul(&base)?; - } - } - Some(acc) -} |