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//! Math compatibility shims: delegates to `std` or `libm` depending on the feature.
//!
//! When the `no_std` feature is active, transcendental functions are not
//! available as inherent `f64` methods; `libm` provides them instead.
//! This module presents a uniform interface so the rest of the crate is
//! feature-agnostic.
#[cfg(not(feature = "no_std"))]
mod inner {
/// Sine, via `std`.
#[inline]
pub fn sin(x: f64) -> f64 {
x.sin()
}
/// Cosine, via `std`.
#[inline]
pub fn cos(x: f64) -> f64 {
x.cos()
}
/// Tangent, via `std`.
#[inline]
pub fn tan(x: f64) -> f64 {
x.tan()
}
/// Arcsine, via `std`.
#[inline]
pub fn asin(x: f64) -> f64 {
x.asin()
}
/// Arccosine, via `std`.
#[inline]
pub fn acos(x: f64) -> f64 {
x.acos()
}
/// Arctangent, via `std`.
#[inline]
pub fn atan(x: f64) -> f64 {
x.atan()
}
/// Inverse hyperbolic tangent, via `std`.
#[inline]
pub fn atanh(x: f64) -> f64 {
x.atanh()
}
/// Four-quadrant arctangent of `y / x`, via `std`.
#[inline]
pub fn atan2(y: f64, x: f64) -> f64 {
y.atan2(x)
}
/// Square root, via `std`.
#[inline]
pub fn sqrt(x: f64) -> f64 {
x.sqrt()
}
/// Cube root, via `std`.
#[inline]
pub fn cbrt(x: f64) -> f64 {
x.cbrt()
}
/// Exponential function, via `std`.
#[inline]
pub fn exp(x: f64) -> f64 {
x.exp()
}
/// Natural logarithm, via `std`.
#[inline]
pub fn ln(x: f64) -> f64 {
x.ln()
}
/// Absolute value, via `std`.
#[inline]
pub fn abs(x: f64) -> f64 {
x.abs()
}
/// Hyperbolic sine, via `std`.
#[inline]
pub fn sinh(x: f64) -> f64 {
x.sinh()
}
/// Hyperbolic cosine, via `std`.
#[inline]
pub fn cosh(x: f64) -> f64 {
x.cosh()
}
/// Hyperbolic tangent, via `std`.
#[inline]
pub fn tanh(x: f64) -> f64 {
x.tanh()
}
/// Euclidean distance `sqrt(x^2 + y^2)` without intermediate
/// overflow/underflow, via `std`.
#[inline]
pub fn hypot(x: f64, y: f64) -> f64 {
x.hypot(y)
}
/// Raises `x` to an integer power, via `std`.
#[inline]
pub fn powi(x: f64, n: i32) -> f64 {
x.powi(n)
}
/// Raises `x` to a floating-point power, via `std`.
#[inline]
pub fn powf(x: f64, y: f64) -> f64 {
x.powf(y)
}
/// Largest integer less than or equal to `x`, via `std`.
#[inline]
pub fn floor(x: f64) -> f64 {
x.floor()
}
/// Smallest integer greater than or equal to `x`, via `std`.
#[inline]
pub fn ceil(x: f64) -> f64 {
x.ceil()
}
/// Rounds `x` to the nearest integer, ties away from zero, via `std`.
#[inline]
pub fn round(x: f64) -> f64 {
x.round()
}
/// Sign of `x`: `1.0`, `-1.0`, or `NaN`/`0.0` preserved, via `std`.
#[inline]
pub fn signum(x: f64) -> f64 {
x.signum()
}
}
#[cfg(feature = "no_std")]
mod inner {
/// Sine, via `libm`.
#[inline]
pub fn sin(x: f64) -> f64 {
libm::sin(x)
}
/// Cosine, via `libm`.
#[inline]
pub fn cos(x: f64) -> f64 {
libm::cos(x)
}
/// Tangent, via `libm`.
#[inline]
pub fn tan(x: f64) -> f64 {
libm::tan(x)
}
/// Arcsine, via `libm`.
#[inline]
pub fn asin(x: f64) -> f64 {
libm::asin(x)
}
/// Arccosine, via `libm`.
#[inline]
pub fn acos(x: f64) -> f64 {
libm::acos(x)
}
/// Arctangent, via `libm`.
#[inline]
pub fn atan(x: f64) -> f64 {
libm::atan(x)
}
/// Inverse hyperbolic tangent, via `libm`.
#[inline]
pub fn atanh(x: f64) -> f64 {
libm::atanh(x)
}
/// Four-quadrant arctangent of `y / x`, via `libm`.
#[inline]
pub fn atan2(y: f64, x: f64) -> f64 {
libm::atan2(y, x)
}
/// Square root, via `libm`.
#[inline]
pub fn sqrt(x: f64) -> f64 {
libm::sqrt(x)
}
/// Cube root, via `libm`.
#[inline]
pub fn cbrt(x: f64) -> f64 {
libm::cbrt(x)
}
/// Exponential function, via `libm`.
#[inline]
pub fn exp(x: f64) -> f64 {
libm::exp(x)
}
/// Natural logarithm, via `libm`.
#[inline]
pub fn ln(x: f64) -> f64 {
libm::log(x)
}
/// Absolute value, via `libm`.
#[inline]
pub fn abs(x: f64) -> f64 {
libm::fabs(x)
}
/// Hyperbolic sine, via `libm`.
#[inline]
pub fn sinh(x: f64) -> f64 {
libm::sinh(x)
}
/// Hyperbolic cosine, via `libm`.
#[inline]
pub fn cosh(x: f64) -> f64 {
libm::cosh(x)
}
/// Hyperbolic tangent, via `libm`.
#[inline]
pub fn tanh(x: f64) -> f64 {
libm::tanh(x)
}
/// Euclidean distance `sqrt(x^2 + y^2)` without intermediate
/// overflow/underflow, via `libm`.
#[inline]
pub fn hypot(x: f64, y: f64) -> f64 {
libm::hypot(x, y)
}
/// Raises `x` to an integer power, via `libm`.
#[inline]
pub fn powi(x: f64, n: i32) -> f64 {
libm::pow(x, n as f64)
}
/// Raises `x` to a floating-point power, via `libm`.
#[inline]
pub fn powf(x: f64, y: f64) -> f64 {
libm::pow(x, y)
}
/// Largest integer less than or equal to `x`, via `libm`.
#[inline]
pub fn floor(x: f64) -> f64 {
libm::floor(x)
}
/// Smallest integer greater than or equal to `x`, via `libm`.
#[inline]
pub fn ceil(x: f64) -> f64 {
libm::ceil(x)
}
/// Rounds `x` to the nearest integer, ties away from zero, via `libm`.
#[inline]
pub fn round(x: f64) -> f64 {
libm::round(x)
}
/// Sign of `x`: `1.0` if positive, `-1.0` if negative, `0.0` otherwise
/// (this `no_std` fallback does not special-case `NaN`/signed-zero the
/// way `f64::signum` does).
#[inline]
pub fn signum(x: f64) -> f64 {
if x > 0.0 {
1.0
} else if x < 0.0 {
-1.0
} else {
0.0
}
}
}
pub use inner::*;