1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! The 32-bit floating point type.
13 //! *[See also the `f32` primitive type](../primitive.f32.html).*
15 #![stable(feature = "rust1", since = "1.0.0")]
16 #![allow(missing_docs)]
21 use num::{FpCategory, ParseFloatError};
23 pub use core::f32::{RADIX, MANTISSA_DIGITS, DIGITS, EPSILON};
24 pub use core::f32::{MIN_EXP, MAX_EXP, MIN_10_EXP};
25 pub use core::f32::{MAX_10_EXP, NAN, INFINITY, NEG_INFINITY};
26 pub use core::f32::{MIN, MIN_POSITIVE, MAX};
27 pub use core::f32::consts;
31 use libc::{c_float, c_int};
34 pub fn cbrtf(n: c_float) -> c_float;
35 pub fn erff(n: c_float) -> c_float;
36 pub fn erfcf(n: c_float) -> c_float;
37 pub fn expm1f(n: c_float) -> c_float;
38 pub fn fdimf(a: c_float, b: c_float) -> c_float;
39 pub fn fmaxf(a: c_float, b: c_float) -> c_float;
40 pub fn fminf(a: c_float, b: c_float) -> c_float;
41 pub fn fmodf(a: c_float, b: c_float) -> c_float;
42 pub fn ilogbf(n: c_float) -> c_int;
43 pub fn logbf(n: c_float) -> c_float;
44 pub fn log1pf(n: c_float) -> c_float;
45 pub fn modff(n: c_float, iptr: &mut c_float) -> c_float;
46 pub fn nextafterf(x: c_float, y: c_float) -> c_float;
47 pub fn tgammaf(n: c_float) -> c_float;
49 #[cfg_attr(all(windows, target_env = "msvc"), link_name = "__lgammaf_r")]
50 pub fn lgammaf_r(n: c_float, sign: &mut c_int) -> c_float;
51 #[cfg_attr(all(windows, target_env = "msvc"), link_name = "_hypotf")]
52 pub fn hypotf(x: c_float, y: c_float) -> c_float;
55 // See the comments in `core::float::Float::floor` for why MSVC is special
57 #[cfg(not(target_env = "msvc"))]
59 pub fn acosf(n: c_float) -> c_float;
60 pub fn asinf(n: c_float) -> c_float;
61 pub fn atan2f(a: c_float, b: c_float) -> c_float;
62 pub fn atanf(n: c_float) -> c_float;
63 pub fn coshf(n: c_float) -> c_float;
64 pub fn frexpf(n: c_float, value: &mut c_int) -> c_float;
65 pub fn ldexpf(x: c_float, n: c_int) -> c_float;
66 pub fn sinhf(n: c_float) -> c_float;
67 pub fn tanf(n: c_float) -> c_float;
68 pub fn tanhf(n: c_float) -> c_float;
71 #[cfg(target_env = "msvc")]
72 pub use self::shims::*;
73 #[cfg(target_env = "msvc")]
75 use libc::{c_float, c_int};
77 pub unsafe fn acosf(n: c_float) -> c_float {
78 f64::acos(n as f64) as c_float
81 pub unsafe fn asinf(n: c_float) -> c_float {
82 f64::asin(n as f64) as c_float
85 pub unsafe fn atan2f(n: c_float, b: c_float) -> c_float {
86 f64::atan2(n as f64, b as f64) as c_float
89 pub unsafe fn atanf(n: c_float) -> c_float {
90 f64::atan(n as f64) as c_float
93 pub unsafe fn coshf(n: c_float) -> c_float {
94 f64::cosh(n as f64) as c_float
97 pub unsafe fn frexpf(x: c_float, value: &mut c_int) -> c_float {
98 let (a, b) = f64::frexp(x as f64);
103 pub unsafe fn ldexpf(x: c_float, n: c_int) -> c_float {
104 f64::ldexp(x as f64, n as isize) as c_float
107 pub unsafe fn sinhf(n: c_float) -> c_float {
108 f64::sinh(n as f64) as c_float
111 pub unsafe fn tanf(n: c_float) -> c_float {
112 f64::tan(n as f64) as c_float
115 pub unsafe fn tanhf(n: c_float) -> c_float {
116 f64::tanh(n as f64) as c_float
123 #[stable(feature = "rust1", since = "1.0.0")]
125 /// Parses a float as with a given radix
126 #[unstable(feature = "float_from_str_radix", reason = "recently moved API",
128 pub fn from_str_radix(s: &str, radix: u32) -> Result<f32, ParseFloatError> {
129 num::Float::from_str_radix(s, radix)
132 /// Returns `true` if this value is `NaN` and false otherwise.
137 /// let nan = f32::NAN;
140 /// assert!(nan.is_nan());
141 /// assert!(!f.is_nan());
143 #[stable(feature = "rust1", since = "1.0.0")]
145 pub fn is_nan(self) -> bool { num::Float::is_nan(self) }
147 /// Returns `true` if this value is positive infinity or negative infinity and
154 /// let inf = f32::INFINITY;
155 /// let neg_inf = f32::NEG_INFINITY;
156 /// let nan = f32::NAN;
158 /// assert!(!f.is_infinite());
159 /// assert!(!nan.is_infinite());
161 /// assert!(inf.is_infinite());
162 /// assert!(neg_inf.is_infinite());
164 #[stable(feature = "rust1", since = "1.0.0")]
166 pub fn is_infinite(self) -> bool { num::Float::is_infinite(self) }
168 /// Returns `true` if this number is neither infinite nor `NaN`.
174 /// let inf = f32::INFINITY;
175 /// let neg_inf = f32::NEG_INFINITY;
176 /// let nan = f32::NAN;
178 /// assert!(f.is_finite());
180 /// assert!(!nan.is_finite());
181 /// assert!(!inf.is_finite());
182 /// assert!(!neg_inf.is_finite());
184 #[stable(feature = "rust1", since = "1.0.0")]
186 pub fn is_finite(self) -> bool { num::Float::is_finite(self) }
188 /// Returns `true` if the number is neither zero, infinite,
189 /// [subnormal][subnormal], or `NaN`.
194 /// let min = f32::MIN_POSITIVE; // 1.17549435e-38f32
195 /// let max = f32::MAX;
196 /// let lower_than_min = 1.0e-40_f32;
197 /// let zero = 0.0_f32;
199 /// assert!(min.is_normal());
200 /// assert!(max.is_normal());
202 /// assert!(!zero.is_normal());
203 /// assert!(!f32::NAN.is_normal());
204 /// assert!(!f32::INFINITY.is_normal());
205 /// // Values between `0` and `min` are Subnormal.
206 /// assert!(!lower_than_min.is_normal());
208 /// [subnormal]: http://en.wikipedia.org/wiki/Denormal_number
209 #[stable(feature = "rust1", since = "1.0.0")]
211 pub fn is_normal(self) -> bool { num::Float::is_normal(self) }
213 /// Returns the floating point category of the number. If only one property
214 /// is going to be tested, it is generally faster to use the specific
215 /// predicate instead.
218 /// use std::num::FpCategory;
221 /// let num = 12.4_f32;
222 /// let inf = f32::INFINITY;
224 /// assert_eq!(num.classify(), FpCategory::Normal);
225 /// assert_eq!(inf.classify(), FpCategory::Infinite);
227 #[stable(feature = "rust1", since = "1.0.0")]
229 pub fn classify(self) -> FpCategory { num::Float::classify(self) }
231 /// Returns the mantissa, base 2 exponent, and sign as integers, respectively.
232 /// The original number can be recovered by `sign * mantissa * 2 ^ exponent`.
233 /// The floating point encoding is documented in the [Reference][floating-point].
236 /// #![feature(float_extras)]
240 /// let num = 2.0f32;
242 /// // (8388608, -22, 1)
243 /// let (mantissa, exponent, sign) = num.integer_decode();
244 /// let sign_f = sign as f32;
245 /// let mantissa_f = mantissa as f32;
246 /// let exponent_f = num.powf(exponent as f32);
248 /// // 1 * 8388608 * 2^(-22) == 2
249 /// let abs_difference = (sign_f * mantissa_f * exponent_f - num).abs();
251 /// assert!(abs_difference <= f32::EPSILON);
253 /// [floating-point]: ../../../../../reference.html#machine-types
254 #[unstable(feature = "float_extras", reason = "signature is undecided",
257 pub fn integer_decode(self) -> (u64, i16, i8) {
258 num::Float::integer_decode(self)
261 /// Returns the largest integer less than or equal to a number.
264 /// let f = 3.99_f32;
267 /// assert_eq!(f.floor(), 3.0);
268 /// assert_eq!(g.floor(), 3.0);
270 #[stable(feature = "rust1", since = "1.0.0")]
272 pub fn floor(self) -> f32 {
275 // On MSVC LLVM will lower many math intrinsics to a call to the
276 // corresponding function. On MSVC, however, many of these functions
277 // aren't actually available as symbols to call, but rather they are all
278 // `static inline` functions in header files. This means that from a C
279 // perspective it's "compatible", but not so much from an ABI
280 // perspective (which we're worried about).
282 // The inline header functions always just cast to a f64 and do their
283 // operation, so we do that here as well, but only for MSVC targets.
285 // Note that there are many MSVC-specific float operations which
286 // redirect to this comment, so `floorf` is just one case of a missing
287 // function on MSVC, but there are many others elsewhere.
288 #[cfg(target_env = "msvc")]
289 fn floorf(f: f32) -> f32 { (f as f64).floor() as f32 }
290 #[cfg(not(target_env = "msvc"))]
291 fn floorf(f: f32) -> f32 { unsafe { intrinsics::floorf32(f) } }
294 /// Returns the smallest integer greater than or equal to a number.
297 /// let f = 3.01_f32;
300 /// assert_eq!(f.ceil(), 4.0);
301 /// assert_eq!(g.ceil(), 4.0);
303 #[stable(feature = "rust1", since = "1.0.0")]
305 pub fn ceil(self) -> f32 {
308 // see notes above in `floor`
309 #[cfg(target_env = "msvc")]
310 fn ceilf(f: f32) -> f32 { (f as f64).ceil() as f32 }
311 #[cfg(not(target_env = "msvc"))]
312 fn ceilf(f: f32) -> f32 { unsafe { intrinsics::ceilf32(f) } }
315 /// Returns the nearest integer to a number. Round half-way cases away from
320 /// let g = -3.3_f32;
322 /// assert_eq!(f.round(), 3.0);
323 /// assert_eq!(g.round(), -3.0);
325 #[stable(feature = "rust1", since = "1.0.0")]
327 pub fn round(self) -> f32 {
328 unsafe { intrinsics::roundf32(self) }
331 /// Returns the integer part of a number.
335 /// let g = -3.7_f32;
337 /// assert_eq!(f.trunc(), 3.0);
338 /// assert_eq!(g.trunc(), -3.0);
340 #[stable(feature = "rust1", since = "1.0.0")]
342 pub fn trunc(self) -> f32 {
343 unsafe { intrinsics::truncf32(self) }
346 /// Returns the fractional part of a number.
352 /// let y = -3.5_f32;
353 /// let abs_difference_x = (x.fract() - 0.5).abs();
354 /// let abs_difference_y = (y.fract() - (-0.5)).abs();
356 /// assert!(abs_difference_x <= f32::EPSILON);
357 /// assert!(abs_difference_y <= f32::EPSILON);
359 #[stable(feature = "rust1", since = "1.0.0")]
361 pub fn fract(self) -> f32 { self - self.trunc() }
363 /// Computes the absolute value of `self`. Returns `NAN` if the
370 /// let y = -3.5_f32;
372 /// let abs_difference_x = (x.abs() - x).abs();
373 /// let abs_difference_y = (y.abs() - (-y)).abs();
375 /// assert!(abs_difference_x <= f32::EPSILON);
376 /// assert!(abs_difference_y <= f32::EPSILON);
378 /// assert!(f32::NAN.abs().is_nan());
380 #[stable(feature = "rust1", since = "1.0.0")]
382 pub fn abs(self) -> f32 { num::Float::abs(self) }
384 /// Returns a number that represents the sign of `self`.
386 /// - `1.0` if the number is positive, `+0.0` or `INFINITY`
387 /// - `-1.0` if the number is negative, `-0.0` or `NEG_INFINITY`
388 /// - `NAN` if the number is `NAN`
395 /// assert_eq!(f.signum(), 1.0);
396 /// assert_eq!(f32::NEG_INFINITY.signum(), -1.0);
398 /// assert!(f32::NAN.signum().is_nan());
400 #[stable(feature = "rust1", since = "1.0.0")]
402 pub fn signum(self) -> f32 { num::Float::signum(self) }
404 /// Returns `true` if `self`'s sign bit is positive, including
405 /// `+0.0` and `INFINITY`.
410 /// let nan = f32::NAN;
412 /// let g = -7.0_f32;
414 /// assert!(f.is_sign_positive());
415 /// assert!(!g.is_sign_positive());
416 /// // Requires both tests to determine if is `NaN`
417 /// assert!(!nan.is_sign_positive() && !nan.is_sign_negative());
419 #[stable(feature = "rust1", since = "1.0.0")]
421 pub fn is_sign_positive(self) -> bool { num::Float::is_positive(self) }
423 /// Returns `true` if `self`'s sign is negative, including `-0.0`
424 /// and `NEG_INFINITY`.
429 /// let nan = f32::NAN;
433 /// assert!(!f.is_sign_negative());
434 /// assert!(g.is_sign_negative());
435 /// // Requires both tests to determine if is `NaN`.
436 /// assert!(!nan.is_sign_positive() && !nan.is_sign_negative());
438 #[stable(feature = "rust1", since = "1.0.0")]
440 pub fn is_sign_negative(self) -> bool { num::Float::is_negative(self) }
442 /// Fused multiply-add. Computes `(self * a) + b` with only one rounding
443 /// error. This produces a more accurate result with better performance than
444 /// a separate multiplication operation followed by an add.
449 /// let m = 10.0_f32;
451 /// let b = 60.0_f32;
454 /// let abs_difference = (m.mul_add(x, b) - (m*x + b)).abs();
456 /// assert!(abs_difference <= f32::EPSILON);
458 #[stable(feature = "rust1", since = "1.0.0")]
460 pub fn mul_add(self, a: f32, b: f32) -> f32 {
461 unsafe { intrinsics::fmaf32(self, a, b) }
464 /// Takes the reciprocal (inverse) of a number, `1/x`.
470 /// let abs_difference = (x.recip() - (1.0/x)).abs();
472 /// assert!(abs_difference <= f32::EPSILON);
474 #[stable(feature = "rust1", since = "1.0.0")]
476 pub fn recip(self) -> f32 { num::Float::recip(self) }
478 /// Raises a number to an integer power.
480 /// Using this function is generally faster than using `powf`
486 /// let abs_difference = (x.powi(2) - x*x).abs();
488 /// assert!(abs_difference <= f32::EPSILON);
490 #[stable(feature = "rust1", since = "1.0.0")]
492 pub fn powi(self, n: i32) -> f32 { num::Float::powi(self, n) }
494 /// Raises a number to a floating point power.
500 /// let abs_difference = (x.powf(2.0) - x*x).abs();
502 /// assert!(abs_difference <= f32::EPSILON);
504 #[stable(feature = "rust1", since = "1.0.0")]
506 pub fn powf(self, n: f32) -> f32 {
507 return powf(self, n);
509 // see notes above in `floor`
510 #[cfg(target_env = "msvc")]
511 fn powf(f: f32, n: f32) -> f32 { (f as f64).powf(n as f64) as f32 }
512 #[cfg(not(target_env = "msvc"))]
513 fn powf(f: f32, n: f32) -> f32 { unsafe { intrinsics::powf32(f, n) } }
516 /// Takes the square root of a number.
518 /// Returns NaN if `self` is a negative number.
523 /// let positive = 4.0_f32;
524 /// let negative = -4.0_f32;
526 /// let abs_difference = (positive.sqrt() - 2.0).abs();
528 /// assert!(abs_difference <= f32::EPSILON);
529 /// assert!(negative.sqrt().is_nan());
531 #[stable(feature = "rust1", since = "1.0.0")]
533 pub fn sqrt(self) -> f32 {
537 unsafe { intrinsics::sqrtf32(self) }
541 /// Returns `e^(self)`, (the exponential function).
546 /// let one = 1.0f32;
548 /// let e = one.exp();
550 /// // ln(e) - 1 == 0
551 /// let abs_difference = (e.ln() - 1.0).abs();
553 /// assert!(abs_difference <= f32::EPSILON);
555 #[stable(feature = "rust1", since = "1.0.0")]
557 pub fn exp(self) -> f32 {
560 // see notes above in `floor`
561 #[cfg(target_env = "msvc")]
562 fn expf(f: f32) -> f32 { (f as f64).exp() as f32 }
563 #[cfg(not(target_env = "msvc"))]
564 fn expf(f: f32) -> f32 { unsafe { intrinsics::expf32(f) } }
567 /// Returns `2^(self)`.
575 /// let abs_difference = (f.exp2() - 4.0).abs();
577 /// assert!(abs_difference <= f32::EPSILON);
579 #[stable(feature = "rust1", since = "1.0.0")]
581 pub fn exp2(self) -> f32 {
582 unsafe { intrinsics::exp2f32(self) }
585 /// Returns the natural logarithm of the number.
590 /// let one = 1.0f32;
592 /// let e = one.exp();
594 /// // ln(e) - 1 == 0
595 /// let abs_difference = (e.ln() - 1.0).abs();
597 /// assert!(abs_difference <= f32::EPSILON);
599 #[stable(feature = "rust1", since = "1.0.0")]
601 pub fn ln(self) -> f32 {
604 // see notes above in `floor`
605 #[cfg(target_env = "msvc")]
606 fn logf(f: f32) -> f32 { (f as f64).ln() as f32 }
607 #[cfg(not(target_env = "msvc"))]
608 fn logf(f: f32) -> f32 { unsafe { intrinsics::logf32(f) } }
611 /// Returns the logarithm of the number with respect to an arbitrary base.
616 /// let ten = 10.0f32;
617 /// let two = 2.0f32;
619 /// // log10(10) - 1 == 0
620 /// let abs_difference_10 = (ten.log(10.0) - 1.0).abs();
622 /// // log2(2) - 1 == 0
623 /// let abs_difference_2 = (two.log(2.0) - 1.0).abs();
625 /// assert!(abs_difference_10 <= f32::EPSILON);
626 /// assert!(abs_difference_2 <= f32::EPSILON);
628 #[stable(feature = "rust1", since = "1.0.0")]
630 pub fn log(self, base: f32) -> f32 { self.ln() / base.ln() }
632 /// Returns the base 2 logarithm of the number.
637 /// let two = 2.0f32;
639 /// // log2(2) - 1 == 0
640 /// let abs_difference = (two.log2() - 1.0).abs();
642 /// assert!(abs_difference <= f32::EPSILON);
644 #[stable(feature = "rust1", since = "1.0.0")]
646 pub fn log2(self) -> f32 {
647 unsafe { intrinsics::log2f32(self) }
650 /// Returns the base 10 logarithm of the number.
655 /// let ten = 10.0f32;
657 /// // log10(10) - 1 == 0
658 /// let abs_difference = (ten.log10() - 1.0).abs();
660 /// assert!(abs_difference <= f32::EPSILON);
662 #[stable(feature = "rust1", since = "1.0.0")]
664 pub fn log10(self) -> f32 {
667 // see notes above in `floor`
668 #[cfg(target_env = "msvc")]
669 fn log10f(f: f32) -> f32 { (f as f64).log10() as f32 }
670 #[cfg(not(target_env = "msvc"))]
671 fn log10f(f: f32) -> f32 { unsafe { intrinsics::log10f32(f) } }
674 /// Converts radians to degrees.
677 /// #![feature(float_extras)]
679 /// use std::f32::{self, consts};
681 /// let angle = consts::PI;
683 /// let abs_difference = (angle.to_degrees() - 180.0).abs();
685 /// assert!(abs_difference <= f32::EPSILON);
687 #[unstable(feature = "float_extras", reason = "desirability is unclear",
690 pub fn to_degrees(self) -> f32 { num::Float::to_degrees(self) }
692 /// Converts degrees to radians.
695 /// #![feature(float_extras)]
697 /// use std::f32::{self, consts};
699 /// let angle = 180.0f32;
701 /// let abs_difference = (angle.to_radians() - consts::PI).abs();
703 /// assert!(abs_difference <= f32::EPSILON);
705 #[unstable(feature = "float_extras", reason = "desirability is unclear",
708 pub fn to_radians(self) -> f32 { num::Float::to_radians(self) }
710 /// Constructs a floating point number of `x*2^exp`.
713 /// #![feature(float_extras)]
716 /// // 3*2^2 - 12 == 0
717 /// let abs_difference = (f32::ldexp(3.0, 2) - 12.0).abs();
719 /// assert!(abs_difference <= f32::EPSILON);
721 #[unstable(feature = "float_extras",
722 reason = "pending integer conventions",
725 pub fn ldexp(x: f32, exp: isize) -> f32 {
726 unsafe { cmath::ldexpf(x, exp as c_int) }
729 /// Breaks the number into a normalized fraction and a base-2 exponent,
732 /// * `self = x * 2^exp`
733 /// * `0.5 <= abs(x) < 1.0`
736 /// #![feature(float_extras)]
742 /// // (1/2)*2^3 -> 1 * 8/2 -> 4.0
743 /// let f = x.frexp();
744 /// let abs_difference_0 = (f.0 - 0.5).abs();
745 /// let abs_difference_1 = (f.1 as f32 - 3.0).abs();
747 /// assert!(abs_difference_0 <= f32::EPSILON);
748 /// assert!(abs_difference_1 <= f32::EPSILON);
750 #[unstable(feature = "float_extras",
751 reason = "pending integer conventions",
754 pub fn frexp(self) -> (f32, isize) {
757 let x = cmath::frexpf(self, &mut exp);
762 /// Returns the next representable floating-point value in the direction of
766 /// #![feature(float_extras)]
772 /// let abs_diff = (x.next_after(2.0) - 1.00000011920928955078125_f32).abs();
774 /// assert!(abs_diff <= f32::EPSILON);
776 #[unstable(feature = "float_extras",
777 reason = "unsure about its place in the world",
780 pub fn next_after(self, other: f32) -> f32 {
781 unsafe { cmath::nextafterf(self, other) }
784 /// Returns the maximum of the two numbers.
790 /// assert_eq!(x.max(y), y);
793 /// If one of the arguments is NaN, then the other argument is returned.
794 #[stable(feature = "rust1", since = "1.0.0")]
796 pub fn max(self, other: f32) -> f32 {
797 unsafe { cmath::fmaxf(self, other) }
800 /// Returns the minimum of the two numbers.
806 /// assert_eq!(x.min(y), x);
809 /// If one of the arguments is NaN, then the other argument is returned.
810 #[stable(feature = "rust1", since = "1.0.0")]
812 pub fn min(self, other: f32) -> f32 {
813 unsafe { cmath::fminf(self, other) }
816 /// The positive difference of two numbers.
818 /// * If `self <= other`: `0:0`
819 /// * Else: `self - other`
827 /// let abs_difference_x = (x.abs_sub(1.0) - 2.0).abs();
828 /// let abs_difference_y = (y.abs_sub(1.0) - 0.0).abs();
830 /// assert!(abs_difference_x <= f32::EPSILON);
831 /// assert!(abs_difference_y <= f32::EPSILON);
833 #[stable(feature = "rust1", since = "1.0.0")]
835 pub fn abs_sub(self, other: f32) -> f32 {
836 unsafe { cmath::fdimf(self, other) }
839 /// Takes the cubic root of a number.
846 /// // x^(1/3) - 2 == 0
847 /// let abs_difference = (x.cbrt() - 2.0).abs();
849 /// assert!(abs_difference <= f32::EPSILON);
851 #[stable(feature = "rust1", since = "1.0.0")]
853 pub fn cbrt(self) -> f32 {
854 unsafe { cmath::cbrtf(self) }
857 /// Calculates the length of the hypotenuse of a right-angle triangle given
858 /// legs of length `x` and `y`.
866 /// // sqrt(x^2 + y^2)
867 /// let abs_difference = (x.hypot(y) - (x.powi(2) + y.powi(2)).sqrt()).abs();
869 /// assert!(abs_difference <= f32::EPSILON);
871 #[stable(feature = "rust1", since = "1.0.0")]
873 pub fn hypot(self, other: f32) -> f32 {
874 unsafe { cmath::hypotf(self, other) }
877 /// Computes the sine of a number (in radians).
882 /// let x = f32::consts::PI/2.0;
884 /// let abs_difference = (x.sin() - 1.0).abs();
886 /// assert!(abs_difference <= f32::EPSILON);
888 #[stable(feature = "rust1", since = "1.0.0")]
890 pub fn sin(self) -> f32 {
893 // see notes in `core::f32::Float::floor`
894 #[cfg(target_env = "msvc")]
895 fn sinf(f: f32) -> f32 { (f as f64).sin() as f32 }
896 #[cfg(not(target_env = "msvc"))]
897 fn sinf(f: f32) -> f32 { unsafe { intrinsics::sinf32(f) } }
900 /// Computes the cosine of a number (in radians).
905 /// let x = 2.0*f32::consts::PI;
907 /// let abs_difference = (x.cos() - 1.0).abs();
909 /// assert!(abs_difference <= f32::EPSILON);
911 #[stable(feature = "rust1", since = "1.0.0")]
913 pub fn cos(self) -> f32 {
916 // see notes in `core::f32::Float::floor`
917 #[cfg(target_env = "msvc")]
918 fn cosf(f: f32) -> f32 { (f as f64).cos() as f32 }
919 #[cfg(not(target_env = "msvc"))]
920 fn cosf(f: f32) -> f32 { unsafe { intrinsics::cosf32(f) } }
923 /// Computes the tangent of a number (in radians).
928 /// let x = f64::consts::PI/4.0;
929 /// let abs_difference = (x.tan() - 1.0).abs();
931 /// assert!(abs_difference < 1e-10);
933 #[stable(feature = "rust1", since = "1.0.0")]
935 pub fn tan(self) -> f32 {
936 unsafe { cmath::tanf(self) }
939 /// Computes the arcsine of a number. Return value is in radians in
940 /// the range [-pi/2, pi/2] or NaN if the number is outside the range
946 /// let f = f32::consts::PI / 2.0;
948 /// // asin(sin(pi/2))
949 /// let abs_difference = f.sin().asin().abs_sub(f32::consts::PI / 2.0);
951 /// assert!(abs_difference <= f32::EPSILON);
953 #[stable(feature = "rust1", since = "1.0.0")]
955 pub fn asin(self) -> f32 {
956 unsafe { cmath::asinf(self) }
959 /// Computes the arccosine of a number. Return value is in radians in
960 /// the range [0, pi] or NaN if the number is outside the range
966 /// let f = f32::consts::PI / 4.0;
968 /// // acos(cos(pi/4))
969 /// let abs_difference = f.cos().acos().abs_sub(f32::consts::PI / 4.0);
971 /// assert!(abs_difference <= f32::EPSILON);
973 #[stable(feature = "rust1", since = "1.0.0")]
975 pub fn acos(self) -> f32 {
976 unsafe { cmath::acosf(self) }
979 /// Computes the arctangent of a number. Return value is in radians in the
980 /// range [-pi/2, pi/2];
988 /// let abs_difference = f.tan().atan().abs_sub(1.0);
990 /// assert!(abs_difference <= f32::EPSILON);
992 #[stable(feature = "rust1", since = "1.0.0")]
994 pub fn atan(self) -> f32 {
995 unsafe { cmath::atanf(self) }
998 /// Computes the four quadrant arctangent of `self` (`y`) and `other` (`x`).
1000 /// * `x = 0`, `y = 0`: `0`
1001 /// * `x >= 0`: `arctan(y/x)` -> `[-pi/2, pi/2]`
1002 /// * `y >= 0`: `arctan(y/x) + pi` -> `(pi/2, pi]`
1003 /// * `y < 0`: `arctan(y/x) - pi` -> `(-pi, -pi/2)`
1008 /// let pi = f32::consts::PI;
1009 /// // All angles from horizontal right (+x)
1010 /// // 45 deg counter-clockwise
1011 /// let x1 = 3.0f32;
1012 /// let y1 = -3.0f32;
1014 /// // 135 deg clockwise
1015 /// let x2 = -3.0f32;
1016 /// let y2 = 3.0f32;
1018 /// let abs_difference_1 = (y1.atan2(x1) - (-pi/4.0)).abs();
1019 /// let abs_difference_2 = (y2.atan2(x2) - 3.0*pi/4.0).abs();
1021 /// assert!(abs_difference_1 <= f32::EPSILON);
1022 /// assert!(abs_difference_2 <= f32::EPSILON);
1024 #[stable(feature = "rust1", since = "1.0.0")]
1026 pub fn atan2(self, other: f32) -> f32 {
1027 unsafe { cmath::atan2f(self, other) }
1030 /// Simultaneously computes the sine and cosine of the number, `x`. Returns
1031 /// `(sin(x), cos(x))`.
1036 /// let x = f32::consts::PI/4.0;
1037 /// let f = x.sin_cos();
1039 /// let abs_difference_0 = (f.0 - x.sin()).abs();
1040 /// let abs_difference_1 = (f.1 - x.cos()).abs();
1042 /// assert!(abs_difference_0 <= f32::EPSILON);
1043 /// assert!(abs_difference_0 <= f32::EPSILON);
1045 #[stable(feature = "rust1", since = "1.0.0")]
1047 pub fn sin_cos(self) -> (f32, f32) {
1048 (self.sin(), self.cos())
1051 /// Returns `e^(self) - 1` in a way that is accurate even if the
1052 /// number is close to zero.
1057 /// // e^(ln(7)) - 1
1058 /// let abs_difference = x.ln().exp_m1().abs_sub(6.0);
1060 /// assert!(abs_difference < 1e-10);
1062 #[stable(feature = "rust1", since = "1.0.0")]
1064 pub fn exp_m1(self) -> f32 {
1065 unsafe { cmath::expm1f(self) }
1068 /// Returns `ln(1+n)` (natural logarithm) more accurately than if
1069 /// the operations were performed separately.
1074 /// let x = f32::consts::E - 1.0;
1076 /// // ln(1 + (e - 1)) == ln(e) == 1
1077 /// let abs_difference = (x.ln_1p() - 1.0).abs();
1079 /// assert!(abs_difference <= f32::EPSILON);
1081 #[stable(feature = "rust1", since = "1.0.0")]
1083 pub fn ln_1p(self) -> f32 {
1084 unsafe { cmath::log1pf(self) }
1087 /// Hyperbolic sine function.
1092 /// let e = f32::consts::E;
1095 /// let f = x.sinh();
1096 /// // Solving sinh() at 1 gives `(e^2-1)/(2e)`
1097 /// let g = (e*e - 1.0)/(2.0*e);
1098 /// let abs_difference = (f - g).abs();
1100 /// assert!(abs_difference <= f32::EPSILON);
1102 #[stable(feature = "rust1", since = "1.0.0")]
1104 pub fn sinh(self) -> f32 {
1105 unsafe { cmath::sinhf(self) }
1108 /// Hyperbolic cosine function.
1113 /// let e = f32::consts::E;
1115 /// let f = x.cosh();
1116 /// // Solving cosh() at 1 gives this result
1117 /// let g = (e*e + 1.0)/(2.0*e);
1118 /// let abs_difference = f.abs_sub(g);
1121 /// assert!(abs_difference <= f32::EPSILON);
1123 #[stable(feature = "rust1", since = "1.0.0")]
1125 pub fn cosh(self) -> f32 {
1126 unsafe { cmath::coshf(self) }
1129 /// Hyperbolic tangent function.
1134 /// let e = f32::consts::E;
1137 /// let f = x.tanh();
1138 /// // Solving tanh() at 1 gives `(1 - e^(-2))/(1 + e^(-2))`
1139 /// let g = (1.0 - e.powi(-2))/(1.0 + e.powi(-2));
1140 /// let abs_difference = (f - g).abs();
1142 /// assert!(abs_difference <= f32::EPSILON);
1144 #[stable(feature = "rust1", since = "1.0.0")]
1146 pub fn tanh(self) -> f32 {
1147 unsafe { cmath::tanhf(self) }
1150 /// Inverse hyperbolic sine function.
1156 /// let f = x.sinh().asinh();
1158 /// let abs_difference = (f - x).abs();
1160 /// assert!(abs_difference <= f32::EPSILON);
1162 #[stable(feature = "rust1", since = "1.0.0")]
1164 pub fn asinh(self) -> f32 {
1166 NEG_INFINITY => NEG_INFINITY,
1167 x => (x + ((x * x) + 1.0).sqrt()).ln(),
1171 /// Inverse hyperbolic cosine function.
1177 /// let f = x.cosh().acosh();
1179 /// let abs_difference = (f - x).abs();
1181 /// assert!(abs_difference <= f32::EPSILON);
1183 #[stable(feature = "rust1", since = "1.0.0")]
1185 pub fn acosh(self) -> f32 {
1187 x if x < 1.0 => ::f32::NAN,
1188 x => (x + ((x * x) - 1.0).sqrt()).ln(),
1192 /// Inverse hyperbolic tangent function.
1197 /// let e = f32::consts::E;
1198 /// let f = e.tanh().atanh();
1200 /// let abs_difference = f.abs_sub(e);
1202 /// assert!(abs_difference <= f32::EPSILON);
1204 #[stable(feature = "rust1", since = "1.0.0")]
1206 pub fn atanh(self) -> f32 {
1207 0.5 * ((2.0 * self) / (1.0 - self)).ln_1p()
1216 use num::FpCategory as Fp;
1220 test_num(10f32, 2f32);
1225 assert_eq!(NAN.min(2.0), 2.0);
1226 assert_eq!(2.0f32.min(NAN), 2.0);
1231 assert_eq!(NAN.max(2.0), 2.0);
1232 assert_eq!(2.0f32.max(NAN), 2.0);
1237 let nan: f32 = f32::NAN;
1238 assert!(nan.is_nan());
1239 assert!(!nan.is_infinite());
1240 assert!(!nan.is_finite());
1241 assert!(!nan.is_normal());
1242 assert!(!nan.is_sign_positive());
1243 assert!(!nan.is_sign_negative());
1244 assert_eq!(Fp::Nan, nan.classify());
1248 fn test_infinity() {
1249 let inf: f32 = f32::INFINITY;
1250 assert!(inf.is_infinite());
1251 assert!(!inf.is_finite());
1252 assert!(inf.is_sign_positive());
1253 assert!(!inf.is_sign_negative());
1254 assert!(!inf.is_nan());
1255 assert!(!inf.is_normal());
1256 assert_eq!(Fp::Infinite, inf.classify());
1260 fn test_neg_infinity() {
1261 let neg_inf: f32 = f32::NEG_INFINITY;
1262 assert!(neg_inf.is_infinite());
1263 assert!(!neg_inf.is_finite());
1264 assert!(!neg_inf.is_sign_positive());
1265 assert!(neg_inf.is_sign_negative());
1266 assert!(!neg_inf.is_nan());
1267 assert!(!neg_inf.is_normal());
1268 assert_eq!(Fp::Infinite, neg_inf.classify());
1273 let zero: f32 = 0.0f32;
1274 assert_eq!(0.0, zero);
1275 assert!(!zero.is_infinite());
1276 assert!(zero.is_finite());
1277 assert!(zero.is_sign_positive());
1278 assert!(!zero.is_sign_negative());
1279 assert!(!zero.is_nan());
1280 assert!(!zero.is_normal());
1281 assert_eq!(Fp::Zero, zero.classify());
1285 fn test_neg_zero() {
1286 let neg_zero: f32 = -0.0;
1287 assert_eq!(0.0, neg_zero);
1288 assert!(!neg_zero.is_infinite());
1289 assert!(neg_zero.is_finite());
1290 assert!(!neg_zero.is_sign_positive());
1291 assert!(neg_zero.is_sign_negative());
1292 assert!(!neg_zero.is_nan());
1293 assert!(!neg_zero.is_normal());
1294 assert_eq!(Fp::Zero, neg_zero.classify());
1299 let one: f32 = 1.0f32;
1300 assert_eq!(1.0, one);
1301 assert!(!one.is_infinite());
1302 assert!(one.is_finite());
1303 assert!(one.is_sign_positive());
1304 assert!(!one.is_sign_negative());
1305 assert!(!one.is_nan());
1306 assert!(one.is_normal());
1307 assert_eq!(Fp::Normal, one.classify());
1312 let nan: f32 = f32::NAN;
1313 let inf: f32 = f32::INFINITY;
1314 let neg_inf: f32 = f32::NEG_INFINITY;
1315 assert!(nan.is_nan());
1316 assert!(!0.0f32.is_nan());
1317 assert!(!5.3f32.is_nan());
1318 assert!(!(-10.732f32).is_nan());
1319 assert!(!inf.is_nan());
1320 assert!(!neg_inf.is_nan());
1324 fn test_is_infinite() {
1325 let nan: f32 = f32::NAN;
1326 let inf: f32 = f32::INFINITY;
1327 let neg_inf: f32 = f32::NEG_INFINITY;
1328 assert!(!nan.is_infinite());
1329 assert!(inf.is_infinite());
1330 assert!(neg_inf.is_infinite());
1331 assert!(!0.0f32.is_infinite());
1332 assert!(!42.8f32.is_infinite());
1333 assert!(!(-109.2f32).is_infinite());
1337 fn test_is_finite() {
1338 let nan: f32 = f32::NAN;
1339 let inf: f32 = f32::INFINITY;
1340 let neg_inf: f32 = f32::NEG_INFINITY;
1341 assert!(!nan.is_finite());
1342 assert!(!inf.is_finite());
1343 assert!(!neg_inf.is_finite());
1344 assert!(0.0f32.is_finite());
1345 assert!(42.8f32.is_finite());
1346 assert!((-109.2f32).is_finite());
1350 fn test_is_normal() {
1351 let nan: f32 = f32::NAN;
1352 let inf: f32 = f32::INFINITY;
1353 let neg_inf: f32 = f32::NEG_INFINITY;
1354 let zero: f32 = 0.0f32;
1355 let neg_zero: f32 = -0.0;
1356 assert!(!nan.is_normal());
1357 assert!(!inf.is_normal());
1358 assert!(!neg_inf.is_normal());
1359 assert!(!zero.is_normal());
1360 assert!(!neg_zero.is_normal());
1361 assert!(1f32.is_normal());
1362 assert!(1e-37f32.is_normal());
1363 assert!(!1e-38f32.is_normal());
1367 fn test_classify() {
1368 let nan: f32 = f32::NAN;
1369 let inf: f32 = f32::INFINITY;
1370 let neg_inf: f32 = f32::NEG_INFINITY;
1371 let zero: f32 = 0.0f32;
1372 let neg_zero: f32 = -0.0;
1373 assert_eq!(nan.classify(), Fp::Nan);
1374 assert_eq!(inf.classify(), Fp::Infinite);
1375 assert_eq!(neg_inf.classify(), Fp::Infinite);
1376 assert_eq!(zero.classify(), Fp::Zero);
1377 assert_eq!(neg_zero.classify(), Fp::Zero);
1378 assert_eq!(1f32.classify(), Fp::Normal);
1379 assert_eq!(1e-37f32.classify(), Fp::Normal);
1380 assert_eq!(1e-38f32.classify(), Fp::Subnormal);
1384 fn test_integer_decode() {
1385 assert_eq!(3.14159265359f32.integer_decode(), (13176795, -22, 1));
1386 assert_eq!((-8573.5918555f32).integer_decode(), (8779358, -10, -1));
1387 assert_eq!(2f32.powf(100.0).integer_decode(), (8388608, 77, 1));
1388 assert_eq!(0f32.integer_decode(), (0, -150, 1));
1389 assert_eq!((-0f32).integer_decode(), (0, -150, -1));
1390 assert_eq!(INFINITY.integer_decode(), (8388608, 105, 1));
1391 assert_eq!(NEG_INFINITY.integer_decode(), (8388608, 105, -1));
1392 assert_eq!(NAN.integer_decode(), (12582912, 105, 1));
1397 assert_approx_eq!(1.0f32.floor(), 1.0f32);
1398 assert_approx_eq!(1.3f32.floor(), 1.0f32);
1399 assert_approx_eq!(1.5f32.floor(), 1.0f32);
1400 assert_approx_eq!(1.7f32.floor(), 1.0f32);
1401 assert_approx_eq!(0.0f32.floor(), 0.0f32);
1402 assert_approx_eq!((-0.0f32).floor(), -0.0f32);
1403 assert_approx_eq!((-1.0f32).floor(), -1.0f32);
1404 assert_approx_eq!((-1.3f32).floor(), -2.0f32);
1405 assert_approx_eq!((-1.5f32).floor(), -2.0f32);
1406 assert_approx_eq!((-1.7f32).floor(), -2.0f32);
1411 assert_approx_eq!(1.0f32.ceil(), 1.0f32);
1412 assert_approx_eq!(1.3f32.ceil(), 2.0f32);
1413 assert_approx_eq!(1.5f32.ceil(), 2.0f32);
1414 assert_approx_eq!(1.7f32.ceil(), 2.0f32);
1415 assert_approx_eq!(0.0f32.ceil(), 0.0f32);
1416 assert_approx_eq!((-0.0f32).ceil(), -0.0f32);
1417 assert_approx_eq!((-1.0f32).ceil(), -1.0f32);
1418 assert_approx_eq!((-1.3f32).ceil(), -1.0f32);
1419 assert_approx_eq!((-1.5f32).ceil(), -1.0f32);
1420 assert_approx_eq!((-1.7f32).ceil(), -1.0f32);
1425 assert_approx_eq!(1.0f32.round(), 1.0f32);
1426 assert_approx_eq!(1.3f32.round(), 1.0f32);
1427 assert_approx_eq!(1.5f32.round(), 2.0f32);
1428 assert_approx_eq!(1.7f32.round(), 2.0f32);
1429 assert_approx_eq!(0.0f32.round(), 0.0f32);
1430 assert_approx_eq!((-0.0f32).round(), -0.0f32);
1431 assert_approx_eq!((-1.0f32).round(), -1.0f32);
1432 assert_approx_eq!((-1.3f32).round(), -1.0f32);
1433 assert_approx_eq!((-1.5f32).round(), -2.0f32);
1434 assert_approx_eq!((-1.7f32).round(), -2.0f32);
1439 assert_approx_eq!(1.0f32.trunc(), 1.0f32);
1440 assert_approx_eq!(1.3f32.trunc(), 1.0f32);
1441 assert_approx_eq!(1.5f32.trunc(), 1.0f32);
1442 assert_approx_eq!(1.7f32.trunc(), 1.0f32);
1443 assert_approx_eq!(0.0f32.trunc(), 0.0f32);
1444 assert_approx_eq!((-0.0f32).trunc(), -0.0f32);
1445 assert_approx_eq!((-1.0f32).trunc(), -1.0f32);
1446 assert_approx_eq!((-1.3f32).trunc(), -1.0f32);
1447 assert_approx_eq!((-1.5f32).trunc(), -1.0f32);
1448 assert_approx_eq!((-1.7f32).trunc(), -1.0f32);
1453 assert_approx_eq!(1.0f32.fract(), 0.0f32);
1454 assert_approx_eq!(1.3f32.fract(), 0.3f32);
1455 assert_approx_eq!(1.5f32.fract(), 0.5f32);
1456 assert_approx_eq!(1.7f32.fract(), 0.7f32);
1457 assert_approx_eq!(0.0f32.fract(), 0.0f32);
1458 assert_approx_eq!((-0.0f32).fract(), -0.0f32);
1459 assert_approx_eq!((-1.0f32).fract(), -0.0f32);
1460 assert_approx_eq!((-1.3f32).fract(), -0.3f32);
1461 assert_approx_eq!((-1.5f32).fract(), -0.5f32);
1462 assert_approx_eq!((-1.7f32).fract(), -0.7f32);
1467 assert_eq!(INFINITY.abs(), INFINITY);
1468 assert_eq!(1f32.abs(), 1f32);
1469 assert_eq!(0f32.abs(), 0f32);
1470 assert_eq!((-0f32).abs(), 0f32);
1471 assert_eq!((-1f32).abs(), 1f32);
1472 assert_eq!(NEG_INFINITY.abs(), INFINITY);
1473 assert_eq!((1f32/NEG_INFINITY).abs(), 0f32);
1474 assert!(NAN.abs().is_nan());
1479 assert_eq!(INFINITY.signum(), 1f32);
1480 assert_eq!(1f32.signum(), 1f32);
1481 assert_eq!(0f32.signum(), 1f32);
1482 assert_eq!((-0f32).signum(), -1f32);
1483 assert_eq!((-1f32).signum(), -1f32);
1484 assert_eq!(NEG_INFINITY.signum(), -1f32);
1485 assert_eq!((1f32/NEG_INFINITY).signum(), -1f32);
1486 assert!(NAN.signum().is_nan());
1490 fn test_is_sign_positive() {
1491 assert!(INFINITY.is_sign_positive());
1492 assert!(1f32.is_sign_positive());
1493 assert!(0f32.is_sign_positive());
1494 assert!(!(-0f32).is_sign_positive());
1495 assert!(!(-1f32).is_sign_positive());
1496 assert!(!NEG_INFINITY.is_sign_positive());
1497 assert!(!(1f32/NEG_INFINITY).is_sign_positive());
1498 assert!(!NAN.is_sign_positive());
1502 fn test_is_sign_negative() {
1503 assert!(!INFINITY.is_sign_negative());
1504 assert!(!1f32.is_sign_negative());
1505 assert!(!0f32.is_sign_negative());
1506 assert!((-0f32).is_sign_negative());
1507 assert!((-1f32).is_sign_negative());
1508 assert!(NEG_INFINITY.is_sign_negative());
1509 assert!((1f32/NEG_INFINITY).is_sign_negative());
1510 assert!(!NAN.is_sign_negative());
1515 let nan: f32 = f32::NAN;
1516 let inf: f32 = f32::INFINITY;
1517 let neg_inf: f32 = f32::NEG_INFINITY;
1518 assert_approx_eq!(12.3f32.mul_add(4.5, 6.7), 62.05);
1519 assert_approx_eq!((-12.3f32).mul_add(-4.5, -6.7), 48.65);
1520 assert_approx_eq!(0.0f32.mul_add(8.9, 1.2), 1.2);
1521 assert_approx_eq!(3.4f32.mul_add(-0.0, 5.6), 5.6);
1522 assert!(nan.mul_add(7.8, 9.0).is_nan());
1523 assert_eq!(inf.mul_add(7.8, 9.0), inf);
1524 assert_eq!(neg_inf.mul_add(7.8, 9.0), neg_inf);
1525 assert_eq!(8.9f32.mul_add(inf, 3.2), inf);
1526 assert_eq!((-3.2f32).mul_add(2.4, neg_inf), neg_inf);
1531 let nan: f32 = f32::NAN;
1532 let inf: f32 = f32::INFINITY;
1533 let neg_inf: f32 = f32::NEG_INFINITY;
1534 assert_eq!(1.0f32.recip(), 1.0);
1535 assert_eq!(2.0f32.recip(), 0.5);
1536 assert_eq!((-0.4f32).recip(), -2.5);
1537 assert_eq!(0.0f32.recip(), inf);
1538 assert!(nan.recip().is_nan());
1539 assert_eq!(inf.recip(), 0.0);
1540 assert_eq!(neg_inf.recip(), 0.0);
1545 let nan: f32 = f32::NAN;
1546 let inf: f32 = f32::INFINITY;
1547 let neg_inf: f32 = f32::NEG_INFINITY;
1548 assert_eq!(1.0f32.powi(1), 1.0);
1549 assert_approx_eq!((-3.1f32).powi(2), 9.61);
1550 assert_approx_eq!(5.9f32.powi(-2), 0.028727);
1551 assert_eq!(8.3f32.powi(0), 1.0);
1552 assert!(nan.powi(2).is_nan());
1553 assert_eq!(inf.powi(3), inf);
1554 assert_eq!(neg_inf.powi(2), inf);
1559 let nan: f32 = f32::NAN;
1560 let inf: f32 = f32::INFINITY;
1561 let neg_inf: f32 = f32::NEG_INFINITY;
1562 assert_eq!(1.0f32.powf(1.0), 1.0);
1563 assert_approx_eq!(3.4f32.powf(4.5), 246.408218);
1564 assert_approx_eq!(2.7f32.powf(-3.2), 0.041652);
1565 assert_approx_eq!((-3.1f32).powf(2.0), 9.61);
1566 assert_approx_eq!(5.9f32.powf(-2.0), 0.028727);
1567 assert_eq!(8.3f32.powf(0.0), 1.0);
1568 assert!(nan.powf(2.0).is_nan());
1569 assert_eq!(inf.powf(2.0), inf);
1570 assert_eq!(neg_inf.powf(3.0), neg_inf);
1574 fn test_sqrt_domain() {
1575 assert!(NAN.sqrt().is_nan());
1576 assert!(NEG_INFINITY.sqrt().is_nan());
1577 assert!((-1.0f32).sqrt().is_nan());
1578 assert_eq!((-0.0f32).sqrt(), -0.0);
1579 assert_eq!(0.0f32.sqrt(), 0.0);
1580 assert_eq!(1.0f32.sqrt(), 1.0);
1581 assert_eq!(INFINITY.sqrt(), INFINITY);
1586 assert_eq!(1.0, 0.0f32.exp());
1587 assert_approx_eq!(2.718282, 1.0f32.exp());
1588 assert_approx_eq!(148.413162, 5.0f32.exp());
1590 let inf: f32 = f32::INFINITY;
1591 let neg_inf: f32 = f32::NEG_INFINITY;
1592 let nan: f32 = f32::NAN;
1593 assert_eq!(inf, inf.exp());
1594 assert_eq!(0.0, neg_inf.exp());
1595 assert!(nan.exp().is_nan());
1600 assert_eq!(32.0, 5.0f32.exp2());
1601 assert_eq!(1.0, 0.0f32.exp2());
1603 let inf: f32 = f32::INFINITY;
1604 let neg_inf: f32 = f32::NEG_INFINITY;
1605 let nan: f32 = f32::NAN;
1606 assert_eq!(inf, inf.exp2());
1607 assert_eq!(0.0, neg_inf.exp2());
1608 assert!(nan.exp2().is_nan());
1613 let nan: f32 = f32::NAN;
1614 let inf: f32 = f32::INFINITY;
1615 let neg_inf: f32 = f32::NEG_INFINITY;
1616 assert_approx_eq!(1.0f32.exp().ln(), 1.0);
1617 assert!(nan.ln().is_nan());
1618 assert_eq!(inf.ln(), inf);
1619 assert!(neg_inf.ln().is_nan());
1620 assert!((-2.3f32).ln().is_nan());
1621 assert_eq!((-0.0f32).ln(), neg_inf);
1622 assert_eq!(0.0f32.ln(), neg_inf);
1623 assert_approx_eq!(4.0f32.ln(), 1.386294);
1628 let nan: f32 = f32::NAN;
1629 let inf: f32 = f32::INFINITY;
1630 let neg_inf: f32 = f32::NEG_INFINITY;
1631 assert_eq!(10.0f32.log(10.0), 1.0);
1632 assert_approx_eq!(2.3f32.log(3.5), 0.664858);
1633 assert_eq!(1.0f32.exp().log(1.0f32.exp()), 1.0);
1634 assert!(1.0f32.log(1.0).is_nan());
1635 assert!(1.0f32.log(-13.9).is_nan());
1636 assert!(nan.log(2.3).is_nan());
1637 assert_eq!(inf.log(10.0), inf);
1638 assert!(neg_inf.log(8.8).is_nan());
1639 assert!((-2.3f32).log(0.1).is_nan());
1640 assert_eq!((-0.0f32).log(2.0), neg_inf);
1641 assert_eq!(0.0f32.log(7.0), neg_inf);
1646 let nan: f32 = f32::NAN;
1647 let inf: f32 = f32::INFINITY;
1648 let neg_inf: f32 = f32::NEG_INFINITY;
1649 assert_approx_eq!(10.0f32.log2(), 3.321928);
1650 assert_approx_eq!(2.3f32.log2(), 1.201634);
1651 assert_approx_eq!(1.0f32.exp().log2(), 1.442695);
1652 assert!(nan.log2().is_nan());
1653 assert_eq!(inf.log2(), inf);
1654 assert!(neg_inf.log2().is_nan());
1655 assert!((-2.3f32).log2().is_nan());
1656 assert_eq!((-0.0f32).log2(), neg_inf);
1657 assert_eq!(0.0f32.log2(), neg_inf);
1662 let nan: f32 = f32::NAN;
1663 let inf: f32 = f32::INFINITY;
1664 let neg_inf: f32 = f32::NEG_INFINITY;
1665 assert_eq!(10.0f32.log10(), 1.0);
1666 assert_approx_eq!(2.3f32.log10(), 0.361728);
1667 assert_approx_eq!(1.0f32.exp().log10(), 0.434294);
1668 assert_eq!(1.0f32.log10(), 0.0);
1669 assert!(nan.log10().is_nan());
1670 assert_eq!(inf.log10(), inf);
1671 assert!(neg_inf.log10().is_nan());
1672 assert!((-2.3f32).log10().is_nan());
1673 assert_eq!((-0.0f32).log10(), neg_inf);
1674 assert_eq!(0.0f32.log10(), neg_inf);
1678 fn test_to_degrees() {
1679 let pi: f32 = consts::PI;
1680 let nan: f32 = f32::NAN;
1681 let inf: f32 = f32::INFINITY;
1682 let neg_inf: f32 = f32::NEG_INFINITY;
1683 assert_eq!(0.0f32.to_degrees(), 0.0);
1684 assert_approx_eq!((-5.8f32).to_degrees(), -332.315521);
1685 assert_eq!(pi.to_degrees(), 180.0);
1686 assert!(nan.to_degrees().is_nan());
1687 assert_eq!(inf.to_degrees(), inf);
1688 assert_eq!(neg_inf.to_degrees(), neg_inf);
1692 fn test_to_radians() {
1693 let pi: f32 = consts::PI;
1694 let nan: f32 = f32::NAN;
1695 let inf: f32 = f32::INFINITY;
1696 let neg_inf: f32 = f32::NEG_INFINITY;
1697 assert_eq!(0.0f32.to_radians(), 0.0);
1698 assert_approx_eq!(154.6f32.to_radians(), 2.698279);
1699 assert_approx_eq!((-332.31f32).to_radians(), -5.799903);
1700 assert_eq!(180.0f32.to_radians(), pi);
1701 assert!(nan.to_radians().is_nan());
1702 assert_eq!(inf.to_radians(), inf);
1703 assert_eq!(neg_inf.to_radians(), neg_inf);
1708 // We have to use from_str until base-2 exponents
1709 // are supported in floating-point literals
1710 let f1: f32 = f32::from_str_radix("1p-123", 16).unwrap();
1711 let f2: f32 = f32::from_str_radix("1p-111", 16).unwrap();
1712 let f3: f32 = f32::from_str_radix("1.Cp-12", 16).unwrap();
1713 assert_eq!(f32::ldexp(1f32, -123), f1);
1714 assert_eq!(f32::ldexp(1f32, -111), f2);
1715 assert_eq!(f32::ldexp(1.75f32, -12), f3);
1717 assert_eq!(f32::ldexp(0f32, -123), 0f32);
1718 assert_eq!(f32::ldexp(-0f32, -123), -0f32);
1720 let inf: f32 = f32::INFINITY;
1721 let neg_inf: f32 = f32::NEG_INFINITY;
1722 let nan: f32 = f32::NAN;
1723 assert_eq!(f32::ldexp(inf, -123), inf);
1724 assert_eq!(f32::ldexp(neg_inf, -123), neg_inf);
1725 assert!(f32::ldexp(nan, -123).is_nan());
1730 // We have to use from_str until base-2 exponents
1731 // are supported in floating-point literals
1732 let f1: f32 = f32::from_str_radix("1p-123", 16).unwrap();
1733 let f2: f32 = f32::from_str_radix("1p-111", 16).unwrap();
1734 let f3: f32 = f32::from_str_radix("1.Cp-123", 16).unwrap();
1735 let (x1, exp1) = f1.frexp();
1736 let (x2, exp2) = f2.frexp();
1737 let (x3, exp3) = f3.frexp();
1738 assert_eq!((x1, exp1), (0.5f32, -122));
1739 assert_eq!((x2, exp2), (0.5f32, -110));
1740 assert_eq!((x3, exp3), (0.875f32, -122));
1741 assert_eq!(f32::ldexp(x1, exp1), f1);
1742 assert_eq!(f32::ldexp(x2, exp2), f2);
1743 assert_eq!(f32::ldexp(x3, exp3), f3);
1745 assert_eq!(0f32.frexp(), (0f32, 0));
1746 assert_eq!((-0f32).frexp(), (-0f32, 0));
1749 #[test] #[cfg_attr(windows, ignore)] // FIXME #8755
1750 fn test_frexp_nowin() {
1751 let inf: f32 = f32::INFINITY;
1752 let neg_inf: f32 = f32::NEG_INFINITY;
1753 let nan: f32 = f32::NAN;
1754 assert_eq!(match inf.frexp() { (x, _) => x }, inf);
1755 assert_eq!(match neg_inf.frexp() { (x, _) => x }, neg_inf);
1756 assert!(match nan.frexp() { (x, _) => x.is_nan() })
1761 assert_eq!((-1f32).abs_sub(1f32), 0f32);
1762 assert_eq!(1f32.abs_sub(1f32), 0f32);
1763 assert_eq!(1f32.abs_sub(0f32), 1f32);
1764 assert_eq!(1f32.abs_sub(-1f32), 2f32);
1765 assert_eq!(NEG_INFINITY.abs_sub(0f32), 0f32);
1766 assert_eq!(INFINITY.abs_sub(1f32), INFINITY);
1767 assert_eq!(0f32.abs_sub(NEG_INFINITY), INFINITY);
1768 assert_eq!(0f32.abs_sub(INFINITY), 0f32);
1772 fn test_abs_sub_nowin() {
1773 assert!(NAN.abs_sub(-1f32).is_nan());
1774 assert!(1f32.abs_sub(NAN).is_nan());
1779 assert_eq!(0.0f32.asinh(), 0.0f32);
1780 assert_eq!((-0.0f32).asinh(), -0.0f32);
1782 let inf: f32 = f32::INFINITY;
1783 let neg_inf: f32 = f32::NEG_INFINITY;
1784 let nan: f32 = f32::NAN;
1785 assert_eq!(inf.asinh(), inf);
1786 assert_eq!(neg_inf.asinh(), neg_inf);
1787 assert!(nan.asinh().is_nan());
1788 assert_approx_eq!(2.0f32.asinh(), 1.443635475178810342493276740273105f32);
1789 assert_approx_eq!((-2.0f32).asinh(), -1.443635475178810342493276740273105f32);
1794 assert_eq!(1.0f32.acosh(), 0.0f32);
1795 assert!(0.999f32.acosh().is_nan());
1797 let inf: f32 = f32::INFINITY;
1798 let neg_inf: f32 = f32::NEG_INFINITY;
1799 let nan: f32 = f32::NAN;
1800 assert_eq!(inf.acosh(), inf);
1801 assert!(neg_inf.acosh().is_nan());
1802 assert!(nan.acosh().is_nan());
1803 assert_approx_eq!(2.0f32.acosh(), 1.31695789692481670862504634730796844f32);
1804 assert_approx_eq!(3.0f32.acosh(), 1.76274717403908605046521864995958461f32);
1809 assert_eq!(0.0f32.atanh(), 0.0f32);
1810 assert_eq!((-0.0f32).atanh(), -0.0f32);
1812 let inf32: f32 = f32::INFINITY;
1813 let neg_inf32: f32 = f32::NEG_INFINITY;
1814 assert_eq!(1.0f32.atanh(), inf32);
1815 assert_eq!((-1.0f32).atanh(), neg_inf32);
1817 assert!(2f64.atanh().atanh().is_nan());
1818 assert!((-2f64).atanh().atanh().is_nan());
1820 let inf64: f32 = f32::INFINITY;
1821 let neg_inf64: f32 = f32::NEG_INFINITY;
1822 let nan32: f32 = f32::NAN;
1823 assert!(inf64.atanh().is_nan());
1824 assert!(neg_inf64.atanh().is_nan());
1825 assert!(nan32.atanh().is_nan());
1827 assert_approx_eq!(0.5f32.atanh(), 0.54930614433405484569762261846126285f32);
1828 assert_approx_eq!((-0.5f32).atanh(), -0.54930614433405484569762261846126285f32);
1832 fn test_real_consts() {
1835 let pi: f32 = consts::PI;
1836 let frac_pi_2: f32 = consts::FRAC_PI_2;
1837 let frac_pi_3: f32 = consts::FRAC_PI_3;
1838 let frac_pi_4: f32 = consts::FRAC_PI_4;
1839 let frac_pi_6: f32 = consts::FRAC_PI_6;
1840 let frac_pi_8: f32 = consts::FRAC_PI_8;
1841 let frac_1_pi: f32 = consts::FRAC_1_PI;
1842 let frac_2_pi: f32 = consts::FRAC_2_PI;
1843 let frac_2_sqrtpi: f32 = consts::FRAC_2_SQRT_PI;
1844 let sqrt2: f32 = consts::SQRT_2;
1845 let frac_1_sqrt2: f32 = consts::FRAC_1_SQRT_2;
1846 let e: f32 = consts::E;
1847 let log2_e: f32 = consts::LOG2_E;
1848 let log10_e: f32 = consts::LOG10_E;
1849 let ln_2: f32 = consts::LN_2;
1850 let ln_10: f32 = consts::LN_10;
1852 assert_approx_eq!(frac_pi_2, pi / 2f32);
1853 assert_approx_eq!(frac_pi_3, pi / 3f32);
1854 assert_approx_eq!(frac_pi_4, pi / 4f32);
1855 assert_approx_eq!(frac_pi_6, pi / 6f32);
1856 assert_approx_eq!(frac_pi_8, pi / 8f32);
1857 assert_approx_eq!(frac_1_pi, 1f32 / pi);
1858 assert_approx_eq!(frac_2_pi, 2f32 / pi);
1859 assert_approx_eq!(frac_2_sqrtpi, 2f32 / pi.sqrt());
1860 assert_approx_eq!(sqrt2, 2f32.sqrt());
1861 assert_approx_eq!(frac_1_sqrt2, 1f32 / 2f32.sqrt());
1862 assert_approx_eq!(log2_e, e.log2());
1863 assert_approx_eq!(log10_e, e.log10());
1864 assert_approx_eq!(ln_2, 2f32.ln());
1865 assert_approx_eq!(ln_10, 10f32.ln());