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| author | Fenrir <[email protected]> | 2018-04-14 20:02:05 -0600 |
|---|---|---|
| committer | Fenrir <[email protected]> | 2018-04-21 16:35:01 -0600 |
| commit | b330206f5590d88a2f995321d2ea847ded951d1d (patch) | |
| tree | 4fecd0ca00b754c494e96b13e9837db48de93109 /ctr-std/src/f64.rs | |
| parent | Move more implementation details to `imp` module (diff) | |
| download | archived-ctru-rs-b330206f5590d88a2f995321d2ea847ded951d1d.tar.xz archived-ctru-rs-b330206f5590d88a2f995321d2ea847ded951d1d.zip | |
Update for Rust nightly 2018-04-19
Diffstat (limited to 'ctr-std/src/f64.rs')
| -rw-r--r-- | ctr-std/src/f64.rs | 59 |
1 files changed, 55 insertions, 4 deletions
diff --git a/ctr-std/src/f64.rs b/ctr-std/src/f64.rs index 6f34f17..a958567 100644 --- a/ctr-std/src/f64.rs +++ b/ctr-std/src/f64.rs @@ -315,6 +315,56 @@ impl f64 { unsafe { intrinsics::fmaf64(self, a, b) } } + /// Calculates Euclidean division, the matching method for `mod_euc`. + /// + /// This computes the integer `n` such that + /// `self = n * rhs + self.mod_euc(rhs)`. + /// In other words, the result is `self / rhs` rounded to the integer `n` + /// such that `self >= n * rhs`. + /// + /// ``` + /// #![feature(euclidean_division)] + /// let a: f64 = 7.0; + /// let b = 4.0; + /// assert_eq!(a.div_euc(b), 1.0); // 7.0 > 4.0 * 1.0 + /// assert_eq!((-a).div_euc(b), -2.0); // -7.0 >= 4.0 * -2.0 + /// assert_eq!(a.div_euc(-b), -1.0); // 7.0 >= -4.0 * -1.0 + /// assert_eq!((-a).div_euc(-b), 2.0); // -7.0 >= -4.0 * 2.0 + /// ``` + #[inline] + #[unstable(feature = "euclidean_division", issue = "49048")] + pub fn div_euc(self, rhs: f64) -> f64 { + let q = (self / rhs).trunc(); + if self % rhs < 0.0 { + return if rhs > 0.0 { q - 1.0 } else { q + 1.0 } + } + q + } + + /// Calculates the Euclidean modulo (self mod rhs), which is never negative. + /// + /// In particular, the result `n` satisfies `0 <= n < rhs.abs()`. + /// + /// ``` + /// #![feature(euclidean_division)] + /// let a: f64 = 7.0; + /// let b = 4.0; + /// assert_eq!(a.mod_euc(b), 3.0); + /// assert_eq!((-a).mod_euc(b), 1.0); + /// assert_eq!(a.mod_euc(-b), 3.0); + /// assert_eq!((-a).mod_euc(-b), 1.0); + /// ``` + #[inline] + #[unstable(feature = "euclidean_division", issue = "49048")] + pub fn mod_euc(self, rhs: f64) -> f64 { + let r = self % rhs; + if r < 0.0 { + r + rhs.abs() + } else { + r + } + } + /// Takes the reciprocal (inverse) of a number, `1/x`. /// /// ``` @@ -716,7 +766,7 @@ impl f64 { unsafe { cmath::atan(self) } } - /// Computes the four quadrant arctangent of `self` (`y`) and `other` (`x`). + /// Computes the four quadrant arctangent of `self` (`y`) and `other` (`x`) in radians. /// /// * `x = 0`, `y = 0`: `0` /// * `x >= 0`: `arctan(y/x)` -> `[-pi/2, pi/2]` @@ -727,12 +777,13 @@ impl f64 { /// use std::f64; /// /// let pi = f64::consts::PI; - /// // All angles from horizontal right (+x) - /// // 45 deg counter-clockwise + /// // Positive angles measured counter-clockwise + /// // from positive x axis + /// // -pi/4 radians (45 deg clockwise) /// let x1 = 3.0_f64; /// let y1 = -3.0_f64; /// - /// // 135 deg clockwise + /// // 3pi/4 radians (135 deg counter-clockwise) /// let x2 = -3.0_f64; /// let y2 = 3.0_f64; /// |