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)]
28 #[stable(feature = "rust1", since = "1.0.0")]
29 pub use core::f32::{RADIX, MANTISSA_DIGITS, DIGITS, EPSILON};
30 #[stable(feature = "rust1", since = "1.0.0")]
31 pub use core::f32::{MIN_EXP, MAX_EXP, MIN_10_EXP};
32 #[stable(feature = "rust1", since = "1.0.0")]
33 pub use core::f32::{MAX_10_EXP, NAN, INFINITY, NEG_INFINITY};
34 #[stable(feature = "rust1", since = "1.0.0")]
35 pub use core::f32::{MIN, MIN_POSITIVE, MAX};
36 #[stable(feature = "rust1", since = "1.0.0")]
37 pub use core::f32::consts;
41 use libc::{c_float, c_int};
44 pub fn cbrtf(n: c_float) -> c_float;
45 pub fn erff(n: c_float) -> c_float;
46 pub fn erfcf(n: c_float) -> c_float;
47 pub fn expm1f(n: c_float) -> c_float;
48 pub fn fdimf(a: c_float, b: c_float) -> c_float;
49 pub fn fmaxf(a: c_float, b: c_float) -> c_float;
50 pub fn fminf(a: c_float, b: c_float) -> c_float;
51 pub fn fmodf(a: c_float, b: c_float) -> c_float;
52 pub fn ilogbf(n: c_float) -> c_int;
53 pub fn logbf(n: c_float) -> c_float;
54 pub fn log1pf(n: c_float) -> c_float;
55 pub fn modff(n: c_float, iptr: &mut c_float) -> c_float;
56 pub fn nextafterf(x: c_float, y: c_float) -> c_float;
57 pub fn tgammaf(n: c_float) -> c_float;
59 #[cfg_attr(all(windows, target_env = "msvc"), link_name = "__lgammaf_r")]
60 pub fn lgammaf_r(n: c_float, sign: &mut c_int) -> c_float;
61 #[cfg_attr(all(windows, target_env = "msvc"), link_name = "_hypotf")]
62 pub fn hypotf(x: c_float, y: c_float) -> c_float;
65 // See the comments in the `floor` function for why MSVC is special
67 #[cfg(not(target_env = "msvc"))]
69 pub fn acosf(n: c_float) -> c_float;
70 pub fn asinf(n: c_float) -> c_float;
71 pub fn atan2f(a: c_float, b: c_float) -> c_float;
72 pub fn atanf(n: c_float) -> c_float;
73 pub fn coshf(n: c_float) -> c_float;
74 pub fn frexpf(n: c_float, value: &mut c_int) -> c_float;
75 pub fn ldexpf(x: c_float, n: c_int) -> c_float;
76 pub fn sinhf(n: c_float) -> c_float;
77 pub fn tanf(n: c_float) -> c_float;
78 pub fn tanhf(n: c_float) -> c_float;
81 #[cfg(target_env = "msvc")]
82 pub use self::shims::*;
83 #[cfg(target_env = "msvc")]
85 use libc::{c_float, c_int};
88 pub unsafe fn acosf(n: c_float) -> c_float {
89 f64::acos(n as f64) as c_float
93 pub unsafe fn asinf(n: c_float) -> c_float {
94 f64::asin(n as f64) as c_float
98 pub unsafe fn atan2f(n: c_float, b: c_float) -> c_float {
99 f64::atan2(n as f64, b as f64) as c_float
103 pub unsafe fn atanf(n: c_float) -> c_float {
104 f64::atan(n as f64) as c_float
108 pub unsafe fn coshf(n: c_float) -> c_float {
109 f64::cosh(n as f64) as c_float
114 pub unsafe fn frexpf(x: c_float, value: &mut c_int) -> c_float {
115 let (a, b) = f64::frexp(x as f64);
122 pub unsafe fn ldexpf(x: c_float, n: c_int) -> c_float {
123 f64::ldexp(x as f64, n as isize) as c_float
127 pub unsafe fn sinhf(n: c_float) -> c_float {
128 f64::sinh(n as f64) as c_float
132 pub unsafe fn tanf(n: c_float) -> c_float {
133 f64::tan(n as f64) as c_float
137 pub unsafe fn tanhf(n: c_float) -> c_float {
138 f64::tanh(n as f64) as c_float
146 /// Returns `true` if this value is `NaN` and false otherwise.
151 /// let nan = f32::NAN;
154 /// assert!(nan.is_nan());
155 /// assert!(!f.is_nan());
157 #[stable(feature = "rust1", since = "1.0.0")]
159 pub fn is_nan(self) -> bool { num::Float::is_nan(self) }
161 /// Returns `true` if this value is positive infinity or negative infinity and
168 /// let inf = f32::INFINITY;
169 /// let neg_inf = f32::NEG_INFINITY;
170 /// let nan = f32::NAN;
172 /// assert!(!f.is_infinite());
173 /// assert!(!nan.is_infinite());
175 /// assert!(inf.is_infinite());
176 /// assert!(neg_inf.is_infinite());
178 #[stable(feature = "rust1", since = "1.0.0")]
180 pub fn is_infinite(self) -> bool { num::Float::is_infinite(self) }
182 /// Returns `true` if this number is neither infinite nor `NaN`.
188 /// let inf = f32::INFINITY;
189 /// let neg_inf = f32::NEG_INFINITY;
190 /// let nan = f32::NAN;
192 /// assert!(f.is_finite());
194 /// assert!(!nan.is_finite());
195 /// assert!(!inf.is_finite());
196 /// assert!(!neg_inf.is_finite());
198 #[stable(feature = "rust1", since = "1.0.0")]
200 pub fn is_finite(self) -> bool { num::Float::is_finite(self) }
202 /// Returns `true` if the number is neither zero, infinite,
203 /// [subnormal][subnormal], or `NaN`.
208 /// let min = f32::MIN_POSITIVE; // 1.17549435e-38f32
209 /// let max = f32::MAX;
210 /// let lower_than_min = 1.0e-40_f32;
211 /// let zero = 0.0_f32;
213 /// assert!(min.is_normal());
214 /// assert!(max.is_normal());
216 /// assert!(!zero.is_normal());
217 /// assert!(!f32::NAN.is_normal());
218 /// assert!(!f32::INFINITY.is_normal());
219 /// // Values between `0` and `min` are Subnormal.
220 /// assert!(!lower_than_min.is_normal());
222 /// [subnormal]: https://en.wikipedia.org/wiki/Denormal_number
223 #[stable(feature = "rust1", since = "1.0.0")]
225 pub fn is_normal(self) -> bool { num::Float::is_normal(self) }
227 /// Returns the floating point category of the number. If only one property
228 /// is going to be tested, it is generally faster to use the specific
229 /// predicate instead.
232 /// use std::num::FpCategory;
235 /// let num = 12.4_f32;
236 /// let inf = f32::INFINITY;
238 /// assert_eq!(num.classify(), FpCategory::Normal);
239 /// assert_eq!(inf.classify(), FpCategory::Infinite);
241 #[stable(feature = "rust1", since = "1.0.0")]
243 pub fn classify(self) -> FpCategory { num::Float::classify(self) }
245 /// Returns the mantissa, base 2 exponent, and sign as integers, respectively.
246 /// The original number can be recovered by `sign * mantissa * 2 ^ exponent`.
247 /// The floating point encoding is documented in the [Reference][floating-point].
250 /// #![feature(float_extras)]
254 /// let num = 2.0f32;
256 /// // (8388608, -22, 1)
257 /// let (mantissa, exponent, sign) = num.integer_decode();
258 /// let sign_f = sign as f32;
259 /// let mantissa_f = mantissa as f32;
260 /// let exponent_f = num.powf(exponent as f32);
262 /// // 1 * 8388608 * 2^(-22) == 2
263 /// let abs_difference = (sign_f * mantissa_f * exponent_f - num).abs();
265 /// assert!(abs_difference <= f32::EPSILON);
267 /// [floating-point]: ../reference/types.html#machine-types
268 #[unstable(feature = "float_extras", reason = "signature is undecided",
270 #[rustc_deprecated(since = "1.11.0",
271 reason = "never really came to fruition and easily \
272 implementable outside the standard library")]
275 pub fn integer_decode(self) -> (u64, i16, i8) {
276 num::Float::integer_decode(self)
279 /// Returns the largest integer less than or equal to a number.
282 /// let f = 3.99_f32;
285 /// assert_eq!(f.floor(), 3.0);
286 /// assert_eq!(g.floor(), 3.0);
288 #[stable(feature = "rust1", since = "1.0.0")]
290 pub fn floor(self) -> f32 {
291 // On MSVC LLVM will lower many math intrinsics to a call to the
292 // corresponding function. On MSVC, however, many of these functions
293 // aren't actually available as symbols to call, but rather they are all
294 // `static inline` functions in header files. This means that from a C
295 // perspective it's "compatible", but not so much from an ABI
296 // perspective (which we're worried about).
298 // The inline header functions always just cast to a f64 and do their
299 // operation, so we do that here as well, but only for MSVC targets.
301 // Note that there are many MSVC-specific float operations which
302 // redirect to this comment, so `floorf` is just one case of a missing
303 // function on MSVC, but there are many others elsewhere.
304 #[cfg(target_env = "msvc")]
305 return (self as f64).floor() as f32;
306 #[cfg(not(target_env = "msvc"))]
307 return unsafe { intrinsics::floorf32(self) };
310 /// Returns the smallest integer greater than or equal to a number.
313 /// let f = 3.01_f32;
316 /// assert_eq!(f.ceil(), 4.0);
317 /// assert_eq!(g.ceil(), 4.0);
319 #[stable(feature = "rust1", since = "1.0.0")]
321 pub fn ceil(self) -> f32 {
322 // see notes above in `floor`
323 #[cfg(target_env = "msvc")]
324 return (self as f64).ceil() as f32;
325 #[cfg(not(target_env = "msvc"))]
326 return unsafe { intrinsics::ceilf32(self) };
329 /// Returns the nearest integer to a number. Round half-way cases away from
334 /// let g = -3.3_f32;
336 /// assert_eq!(f.round(), 3.0);
337 /// assert_eq!(g.round(), -3.0);
339 #[stable(feature = "rust1", since = "1.0.0")]
341 pub fn round(self) -> f32 {
342 unsafe { intrinsics::roundf32(self) }
345 /// Returns the integer part of a number.
349 /// let g = -3.7_f32;
351 /// assert_eq!(f.trunc(), 3.0);
352 /// assert_eq!(g.trunc(), -3.0);
354 #[stable(feature = "rust1", since = "1.0.0")]
356 pub fn trunc(self) -> f32 {
357 unsafe { intrinsics::truncf32(self) }
360 /// Returns the fractional part of a number.
366 /// let y = -3.5_f32;
367 /// let abs_difference_x = (x.fract() - 0.5).abs();
368 /// let abs_difference_y = (y.fract() - (-0.5)).abs();
370 /// assert!(abs_difference_x <= f32::EPSILON);
371 /// assert!(abs_difference_y <= f32::EPSILON);
373 #[stable(feature = "rust1", since = "1.0.0")]
375 pub fn fract(self) -> f32 { self - self.trunc() }
377 /// Computes the absolute value of `self`. Returns `NAN` if the
384 /// let y = -3.5_f32;
386 /// let abs_difference_x = (x.abs() - x).abs();
387 /// let abs_difference_y = (y.abs() - (-y)).abs();
389 /// assert!(abs_difference_x <= f32::EPSILON);
390 /// assert!(abs_difference_y <= f32::EPSILON);
392 /// assert!(f32::NAN.abs().is_nan());
394 #[stable(feature = "rust1", since = "1.0.0")]
396 pub fn abs(self) -> f32 { num::Float::abs(self) }
398 /// Returns a number that represents the sign of `self`.
400 /// - `1.0` if the number is positive, `+0.0` or `INFINITY`
401 /// - `-1.0` if the number is negative, `-0.0` or `NEG_INFINITY`
402 /// - `NAN` if the number is `NAN`
409 /// assert_eq!(f.signum(), 1.0);
410 /// assert_eq!(f32::NEG_INFINITY.signum(), -1.0);
412 /// assert!(f32::NAN.signum().is_nan());
414 #[stable(feature = "rust1", since = "1.0.0")]
416 pub fn signum(self) -> f32 { num::Float::signum(self) }
418 /// Returns `true` if `self`'s sign bit is positive, including
419 /// `+0.0` and `INFINITY`.
424 /// let nan = f32::NAN;
426 /// let g = -7.0_f32;
428 /// assert!(f.is_sign_positive());
429 /// assert!(!g.is_sign_positive());
430 /// // Requires both tests to determine if is `NaN`
431 /// assert!(!nan.is_sign_positive() && !nan.is_sign_negative());
433 #[stable(feature = "rust1", since = "1.0.0")]
435 pub fn is_sign_positive(self) -> bool { num::Float::is_sign_positive(self) }
437 /// Returns `true` if `self`'s sign is negative, including `-0.0`
438 /// and `NEG_INFINITY`.
443 /// let nan = f32::NAN;
447 /// assert!(!f.is_sign_negative());
448 /// assert!(g.is_sign_negative());
449 /// // Requires both tests to determine if is `NaN`.
450 /// assert!(!nan.is_sign_positive() && !nan.is_sign_negative());
452 #[stable(feature = "rust1", since = "1.0.0")]
454 pub fn is_sign_negative(self) -> bool { num::Float::is_sign_negative(self) }
456 /// Fused multiply-add. Computes `(self * a) + b` with only one rounding
457 /// error. This produces a more accurate result with better performance than
458 /// a separate multiplication operation followed by an add.
463 /// let m = 10.0_f32;
465 /// let b = 60.0_f32;
468 /// let abs_difference = (m.mul_add(x, b) - (m*x + b)).abs();
470 /// assert!(abs_difference <= f32::EPSILON);
472 #[stable(feature = "rust1", since = "1.0.0")]
474 pub fn mul_add(self, a: f32, b: f32) -> f32 {
475 unsafe { intrinsics::fmaf32(self, a, b) }
478 /// Takes the reciprocal (inverse) of a number, `1/x`.
484 /// let abs_difference = (x.recip() - (1.0/x)).abs();
486 /// assert!(abs_difference <= f32::EPSILON);
488 #[stable(feature = "rust1", since = "1.0.0")]
490 pub fn recip(self) -> f32 { num::Float::recip(self) }
492 /// Raises a number to an integer power.
494 /// Using this function is generally faster than using `powf`
500 /// let abs_difference = (x.powi(2) - x*x).abs();
502 /// assert!(abs_difference <= f32::EPSILON);
504 #[stable(feature = "rust1", since = "1.0.0")]
506 pub fn powi(self, n: i32) -> f32 { num::Float::powi(self, n) }
508 /// Raises a number to a floating point power.
514 /// let abs_difference = (x.powf(2.0) - x*x).abs();
516 /// assert!(abs_difference <= f32::EPSILON);
518 #[stable(feature = "rust1", since = "1.0.0")]
520 pub fn powf(self, n: f32) -> f32 {
521 // see notes above in `floor`
522 #[cfg(target_env = "msvc")]
523 return (self as f64).powf(n as f64) as f32;
524 #[cfg(not(target_env = "msvc"))]
525 return unsafe { intrinsics::powf32(self, n) };
528 /// Takes the square root of a number.
530 /// Returns NaN if `self` is a negative number.
535 /// let positive = 4.0_f32;
536 /// let negative = -4.0_f32;
538 /// let abs_difference = (positive.sqrt() - 2.0).abs();
540 /// assert!(abs_difference <= f32::EPSILON);
541 /// assert!(negative.sqrt().is_nan());
543 #[stable(feature = "rust1", since = "1.0.0")]
545 pub fn sqrt(self) -> f32 {
549 unsafe { intrinsics::sqrtf32(self) }
553 /// Returns `e^(self)`, (the exponential function).
558 /// let one = 1.0f32;
560 /// let e = one.exp();
562 /// // ln(e) - 1 == 0
563 /// let abs_difference = (e.ln() - 1.0).abs();
565 /// assert!(abs_difference <= f32::EPSILON);
567 #[stable(feature = "rust1", since = "1.0.0")]
569 pub fn exp(self) -> f32 {
570 // see notes above in `floor`
571 #[cfg(target_env = "msvc")]
572 return (self as f64).exp() as f32;
573 #[cfg(not(target_env = "msvc"))]
574 return unsafe { intrinsics::expf32(self) };
577 /// Returns `2^(self)`.
585 /// let abs_difference = (f.exp2() - 4.0).abs();
587 /// assert!(abs_difference <= f32::EPSILON);
589 #[stable(feature = "rust1", since = "1.0.0")]
591 pub fn exp2(self) -> f32 {
592 unsafe { intrinsics::exp2f32(self) }
595 /// Returns the natural logarithm of the number.
600 /// let one = 1.0f32;
602 /// let e = one.exp();
604 /// // ln(e) - 1 == 0
605 /// let abs_difference = (e.ln() - 1.0).abs();
607 /// assert!(abs_difference <= f32::EPSILON);
609 #[stable(feature = "rust1", since = "1.0.0")]
611 pub fn ln(self) -> f32 {
612 // see notes above in `floor`
613 #[cfg(target_env = "msvc")]
614 return (self as f64).ln() as f32;
615 #[cfg(not(target_env = "msvc"))]
616 return unsafe { intrinsics::logf32(self) };
619 /// Returns the logarithm of the number with respect to an arbitrary base.
624 /// let ten = 10.0f32;
625 /// let two = 2.0f32;
627 /// // log10(10) - 1 == 0
628 /// let abs_difference_10 = (ten.log(10.0) - 1.0).abs();
630 /// // log2(2) - 1 == 0
631 /// let abs_difference_2 = (two.log(2.0) - 1.0).abs();
633 /// assert!(abs_difference_10 <= f32::EPSILON);
634 /// assert!(abs_difference_2 <= f32::EPSILON);
636 #[stable(feature = "rust1", since = "1.0.0")]
638 pub fn log(self, base: f32) -> f32 { self.ln() / base.ln() }
640 /// Returns the base 2 logarithm of the number.
645 /// let two = 2.0f32;
647 /// // log2(2) - 1 == 0
648 /// let abs_difference = (two.log2() - 1.0).abs();
650 /// assert!(abs_difference <= f32::EPSILON);
652 #[stable(feature = "rust1", since = "1.0.0")]
654 pub fn log2(self) -> f32 {
655 #[cfg(target_os = "android")]
656 return ::sys::android::log2f32(self);
657 #[cfg(not(target_os = "android"))]
658 return unsafe { intrinsics::log2f32(self) };
661 /// Returns the base 10 logarithm of the number.
666 /// let ten = 10.0f32;
668 /// // log10(10) - 1 == 0
669 /// let abs_difference = (ten.log10() - 1.0).abs();
671 /// assert!(abs_difference <= f32::EPSILON);
673 #[stable(feature = "rust1", since = "1.0.0")]
675 pub fn log10(self) -> f32 {
676 // see notes above in `floor`
677 #[cfg(target_env = "msvc")]
678 return (self as f64).log10() as f32;
679 #[cfg(not(target_env = "msvc"))]
680 return unsafe { intrinsics::log10f32(self) };
683 /// Converts radians to degrees.
686 /// use std::f32::{self, consts};
688 /// let angle = consts::PI;
690 /// let abs_difference = (angle.to_degrees() - 180.0).abs();
692 /// assert!(abs_difference <= f32::EPSILON);
694 #[stable(feature = "f32_deg_rad_conversions", since="1.7.0")]
696 pub fn to_degrees(self) -> f32 { num::Float::to_degrees(self) }
698 /// Converts degrees to radians.
701 /// use std::f32::{self, consts};
703 /// let angle = 180.0f32;
705 /// let abs_difference = (angle.to_radians() - consts::PI).abs();
707 /// assert!(abs_difference <= f32::EPSILON);
709 #[stable(feature = "f32_deg_rad_conversions", since="1.7.0")]
711 pub fn to_radians(self) -> f32 { num::Float::to_radians(self) }
713 /// Constructs a floating point number of `x*2^exp`.
716 /// #![feature(float_extras)]
719 /// // 3*2^2 - 12 == 0
720 /// let abs_difference = (f32::ldexp(3.0, 2) - 12.0).abs();
722 /// assert!(abs_difference <= f32::EPSILON);
724 #[unstable(feature = "float_extras",
725 reason = "pending integer conventions",
727 #[rustc_deprecated(since = "1.11.0",
728 reason = "never really came to fruition and easily \
729 implementable outside the standard library")]
731 pub fn ldexp(x: f32, exp: isize) -> f32 {
732 unsafe { cmath::ldexpf(x, exp as c_int) }
735 /// Breaks the number into a normalized fraction and a base-2 exponent,
738 /// * `self = x * 2^exp`
739 /// * `0.5 <= abs(x) < 1.0`
742 /// #![feature(float_extras)]
748 /// // (1/2)*2^3 -> 1 * 8/2 -> 4.0
749 /// let f = x.frexp();
750 /// let abs_difference_0 = (f.0 - 0.5).abs();
751 /// let abs_difference_1 = (f.1 as f32 - 3.0).abs();
753 /// assert!(abs_difference_0 <= f32::EPSILON);
754 /// assert!(abs_difference_1 <= f32::EPSILON);
756 #[unstable(feature = "float_extras",
757 reason = "pending integer conventions",
759 #[rustc_deprecated(since = "1.11.0",
760 reason = "never really came to fruition and easily \
761 implementable outside the standard library")]
763 pub fn frexp(self) -> (f32, isize) {
766 let x = cmath::frexpf(self, &mut exp);
771 /// Returns the next representable floating-point value in the direction of
775 /// #![feature(float_extras)]
781 /// let abs_diff = (x.next_after(2.0) - 1.00000011920928955078125_f32).abs();
783 /// assert!(abs_diff <= f32::EPSILON);
785 #[unstable(feature = "float_extras",
786 reason = "unsure about its place in the world",
788 #[rustc_deprecated(since = "1.11.0",
789 reason = "never really came to fruition and easily \
790 implementable outside the standard library")]
792 pub fn next_after(self, other: f32) -> f32 {
793 unsafe { cmath::nextafterf(self, other) }
796 /// Returns the maximum of the two numbers.
802 /// assert_eq!(x.max(y), y);
805 /// If one of the arguments is NaN, then the other argument is returned.
806 #[stable(feature = "rust1", since = "1.0.0")]
808 pub fn max(self, other: f32) -> f32 {
809 unsafe { cmath::fmaxf(self, other) }
812 /// Returns the minimum of the two numbers.
818 /// assert_eq!(x.min(y), x);
821 /// If one of the arguments is NaN, then the other argument is returned.
822 #[stable(feature = "rust1", since = "1.0.0")]
824 pub fn min(self, other: f32) -> f32 {
825 unsafe { cmath::fminf(self, other) }
828 /// The positive difference of two numbers.
830 /// * If `self <= other`: `0:0`
831 /// * Else: `self - other`
839 /// let abs_difference_x = (x.abs_sub(1.0) - 2.0).abs();
840 /// let abs_difference_y = (y.abs_sub(1.0) - 0.0).abs();
842 /// assert!(abs_difference_x <= f32::EPSILON);
843 /// assert!(abs_difference_y <= f32::EPSILON);
845 #[stable(feature = "rust1", since = "1.0.0")]
847 #[rustc_deprecated(since = "1.10.0",
848 reason = "you probably meant `(self - other).abs()`: \
849 this operation is `(self - other).max(0.0)` (also \
850 known as `fdimf` in C). If you truly need the positive \
851 difference, consider using that expression or the C function \
852 `fdimf`, depending on how you wish to handle NaN (please consider \
853 filing an issue describing your use-case too).")]
854 pub fn abs_sub(self, other: f32) -> f32 {
855 unsafe { cmath::fdimf(self, other) }
858 /// Takes the cubic root of a number.
865 /// // x^(1/3) - 2 == 0
866 /// let abs_difference = (x.cbrt() - 2.0).abs();
868 /// assert!(abs_difference <= f32::EPSILON);
870 #[stable(feature = "rust1", since = "1.0.0")]
872 pub fn cbrt(self) -> f32 {
873 unsafe { cmath::cbrtf(self) }
876 /// Calculates the length of the hypotenuse of a right-angle triangle given
877 /// legs of length `x` and `y`.
885 /// // sqrt(x^2 + y^2)
886 /// let abs_difference = (x.hypot(y) - (x.powi(2) + y.powi(2)).sqrt()).abs();
888 /// assert!(abs_difference <= f32::EPSILON);
890 #[stable(feature = "rust1", since = "1.0.0")]
892 pub fn hypot(self, other: f32) -> f32 {
893 unsafe { cmath::hypotf(self, other) }
896 /// Computes the sine of a number (in radians).
901 /// let x = f32::consts::PI/2.0;
903 /// let abs_difference = (x.sin() - 1.0).abs();
905 /// assert!(abs_difference <= f32::EPSILON);
907 #[stable(feature = "rust1", since = "1.0.0")]
909 pub fn sin(self) -> f32 {
910 // see notes in `core::f32::Float::floor`
911 #[cfg(target_env = "msvc")]
912 return (self as f64).sin() as f32;
913 #[cfg(not(target_env = "msvc"))]
914 return unsafe { intrinsics::sinf32(self) };
917 /// Computes the cosine of a number (in radians).
922 /// let x = 2.0*f32::consts::PI;
924 /// let abs_difference = (x.cos() - 1.0).abs();
926 /// assert!(abs_difference <= f32::EPSILON);
928 #[stable(feature = "rust1", since = "1.0.0")]
930 pub fn cos(self) -> f32 {
931 // see notes in `core::f32::Float::floor`
932 #[cfg(target_env = "msvc")]
933 return (self as f64).cos() as f32;
934 #[cfg(not(target_env = "msvc"))]
935 return unsafe { intrinsics::cosf32(self) };
938 /// Computes the tangent of a number (in radians).
943 /// let x = f32::consts::PI / 4.0;
944 /// let abs_difference = (x.tan() - 1.0).abs();
946 /// assert!(abs_difference <= f32::EPSILON);
948 #[stable(feature = "rust1", since = "1.0.0")]
950 pub fn tan(self) -> f32 {
951 unsafe { cmath::tanf(self) }
954 /// Computes the arcsine of a number. Return value is in radians in
955 /// the range [-pi/2, pi/2] or NaN if the number is outside the range
961 /// let f = f32::consts::PI / 2.0;
963 /// // asin(sin(pi/2))
964 /// let abs_difference = (f.sin().asin() - f32::consts::PI / 2.0).abs();
966 /// assert!(abs_difference <= f32::EPSILON);
968 #[stable(feature = "rust1", since = "1.0.0")]
970 pub fn asin(self) -> f32 {
971 unsafe { cmath::asinf(self) }
974 /// Computes the arccosine of a number. Return value is in radians in
975 /// the range [0, pi] or NaN if the number is outside the range
981 /// let f = f32::consts::PI / 4.0;
983 /// // acos(cos(pi/4))
984 /// let abs_difference = (f.cos().acos() - f32::consts::PI / 4.0).abs();
986 /// assert!(abs_difference <= f32::EPSILON);
988 #[stable(feature = "rust1", since = "1.0.0")]
990 pub fn acos(self) -> f32 {
991 unsafe { cmath::acosf(self) }
994 /// Computes the arctangent of a number. Return value is in radians in the
995 /// range [-pi/2, pi/2];
1003 /// let abs_difference = (f.tan().atan() - 1.0).abs();
1005 /// assert!(abs_difference <= f32::EPSILON);
1007 #[stable(feature = "rust1", since = "1.0.0")]
1009 pub fn atan(self) -> f32 {
1010 unsafe { cmath::atanf(self) }
1013 /// Computes the four quadrant arctangent of `self` (`y`) and `other` (`x`).
1015 /// * `x = 0`, `y = 0`: `0`
1016 /// * `x >= 0`: `arctan(y/x)` -> `[-pi/2, pi/2]`
1017 /// * `y >= 0`: `arctan(y/x) + pi` -> `(pi/2, pi]`
1018 /// * `y < 0`: `arctan(y/x) - pi` -> `(-pi, -pi/2)`
1023 /// let pi = f32::consts::PI;
1024 /// // All angles from horizontal right (+x)
1025 /// // 45 deg counter-clockwise
1026 /// let x1 = 3.0f32;
1027 /// let y1 = -3.0f32;
1029 /// // 135 deg clockwise
1030 /// let x2 = -3.0f32;
1031 /// let y2 = 3.0f32;
1033 /// let abs_difference_1 = (y1.atan2(x1) - (-pi/4.0)).abs();
1034 /// let abs_difference_2 = (y2.atan2(x2) - 3.0*pi/4.0).abs();
1036 /// assert!(abs_difference_1 <= f32::EPSILON);
1037 /// assert!(abs_difference_2 <= f32::EPSILON);
1039 #[stable(feature = "rust1", since = "1.0.0")]
1041 pub fn atan2(self, other: f32) -> f32 {
1042 unsafe { cmath::atan2f(self, other) }
1045 /// Simultaneously computes the sine and cosine of the number, `x`. Returns
1046 /// `(sin(x), cos(x))`.
1051 /// let x = f32::consts::PI/4.0;
1052 /// let f = x.sin_cos();
1054 /// let abs_difference_0 = (f.0 - x.sin()).abs();
1055 /// let abs_difference_1 = (f.1 - x.cos()).abs();
1057 /// assert!(abs_difference_0 <= f32::EPSILON);
1058 /// assert!(abs_difference_1 <= f32::EPSILON);
1060 #[stable(feature = "rust1", since = "1.0.0")]
1062 pub fn sin_cos(self) -> (f32, f32) {
1063 (self.sin(), self.cos())
1066 /// Returns `e^(self) - 1` in a way that is accurate even if the
1067 /// number is close to zero.
1074 /// // e^(ln(6)) - 1
1075 /// let abs_difference = (x.ln().exp_m1() - 5.0).abs();
1077 /// assert!(abs_difference <= f32::EPSILON);
1079 #[stable(feature = "rust1", since = "1.0.0")]
1081 pub fn exp_m1(self) -> f32 {
1082 unsafe { cmath::expm1f(self) }
1085 /// Returns `ln(1+n)` (natural logarithm) more accurately than if
1086 /// the operations were performed separately.
1091 /// let x = f32::consts::E - 1.0;
1093 /// // ln(1 + (e - 1)) == ln(e) == 1
1094 /// let abs_difference = (x.ln_1p() - 1.0).abs();
1096 /// assert!(abs_difference <= f32::EPSILON);
1098 #[stable(feature = "rust1", since = "1.0.0")]
1100 pub fn ln_1p(self) -> f32 {
1101 unsafe { cmath::log1pf(self) }
1104 /// Hyperbolic sine function.
1109 /// let e = f32::consts::E;
1112 /// let f = x.sinh();
1113 /// // Solving sinh() at 1 gives `(e^2-1)/(2e)`
1114 /// let g = (e*e - 1.0)/(2.0*e);
1115 /// let abs_difference = (f - g).abs();
1117 /// assert!(abs_difference <= f32::EPSILON);
1119 #[stable(feature = "rust1", since = "1.0.0")]
1121 pub fn sinh(self) -> f32 {
1122 unsafe { cmath::sinhf(self) }
1125 /// Hyperbolic cosine function.
1130 /// let e = f32::consts::E;
1132 /// let f = x.cosh();
1133 /// // Solving cosh() at 1 gives this result
1134 /// let g = (e*e + 1.0)/(2.0*e);
1135 /// let abs_difference = (f - g).abs();
1138 /// assert!(abs_difference <= f32::EPSILON);
1140 #[stable(feature = "rust1", since = "1.0.0")]
1142 pub fn cosh(self) -> f32 {
1143 unsafe { cmath::coshf(self) }
1146 /// Hyperbolic tangent function.
1151 /// let e = f32::consts::E;
1154 /// let f = x.tanh();
1155 /// // Solving tanh() at 1 gives `(1 - e^(-2))/(1 + e^(-2))`
1156 /// let g = (1.0 - e.powi(-2))/(1.0 + e.powi(-2));
1157 /// let abs_difference = (f - g).abs();
1159 /// assert!(abs_difference <= f32::EPSILON);
1161 #[stable(feature = "rust1", since = "1.0.0")]
1163 pub fn tanh(self) -> f32 {
1164 unsafe { cmath::tanhf(self) }
1167 /// Inverse hyperbolic sine function.
1173 /// let f = x.sinh().asinh();
1175 /// let abs_difference = (f - x).abs();
1177 /// assert!(abs_difference <= f32::EPSILON);
1179 #[stable(feature = "rust1", since = "1.0.0")]
1181 pub fn asinh(self) -> f32 {
1182 if self == NEG_INFINITY {
1185 (self + ((self * self) + 1.0).sqrt()).ln()
1189 /// Inverse hyperbolic cosine function.
1195 /// let f = x.cosh().acosh();
1197 /// let abs_difference = (f - x).abs();
1199 /// assert!(abs_difference <= f32::EPSILON);
1201 #[stable(feature = "rust1", since = "1.0.0")]
1203 pub fn acosh(self) -> f32 {
1205 x if x < 1.0 => ::f32::NAN,
1206 x => (x + ((x * x) - 1.0).sqrt()).ln(),
1210 /// Inverse hyperbolic tangent function.
1215 /// let e = f32::consts::E;
1216 /// let f = e.tanh().atanh();
1218 /// let abs_difference = (f - e).abs();
1220 /// assert!(abs_difference <= 1e-5);
1222 #[stable(feature = "rust1", since = "1.0.0")]
1224 pub fn atanh(self) -> f32 {
1225 0.5 * ((2.0 * self) / (1.0 - self)).ln_1p()
1234 use num::FpCategory as Fp;
1238 test_num(10f32, 2f32);
1243 assert_eq!(NAN.min(2.0), 2.0);
1244 assert_eq!(2.0f32.min(NAN), 2.0);
1249 assert_eq!(NAN.max(2.0), 2.0);
1250 assert_eq!(2.0f32.max(NAN), 2.0);
1255 let nan: f32 = f32::NAN;
1256 assert!(nan.is_nan());
1257 assert!(!nan.is_infinite());
1258 assert!(!nan.is_finite());
1259 assert!(!nan.is_normal());
1260 assert!(!nan.is_sign_positive());
1261 assert!(!nan.is_sign_negative());
1262 assert_eq!(Fp::Nan, nan.classify());
1266 fn test_infinity() {
1267 let inf: f32 = f32::INFINITY;
1268 assert!(inf.is_infinite());
1269 assert!(!inf.is_finite());
1270 assert!(inf.is_sign_positive());
1271 assert!(!inf.is_sign_negative());
1272 assert!(!inf.is_nan());
1273 assert!(!inf.is_normal());
1274 assert_eq!(Fp::Infinite, inf.classify());
1278 fn test_neg_infinity() {
1279 let neg_inf: f32 = f32::NEG_INFINITY;
1280 assert!(neg_inf.is_infinite());
1281 assert!(!neg_inf.is_finite());
1282 assert!(!neg_inf.is_sign_positive());
1283 assert!(neg_inf.is_sign_negative());
1284 assert!(!neg_inf.is_nan());
1285 assert!(!neg_inf.is_normal());
1286 assert_eq!(Fp::Infinite, neg_inf.classify());
1291 let zero: f32 = 0.0f32;
1292 assert_eq!(0.0, zero);
1293 assert!(!zero.is_infinite());
1294 assert!(zero.is_finite());
1295 assert!(zero.is_sign_positive());
1296 assert!(!zero.is_sign_negative());
1297 assert!(!zero.is_nan());
1298 assert!(!zero.is_normal());
1299 assert_eq!(Fp::Zero, zero.classify());
1303 fn test_neg_zero() {
1304 let neg_zero: f32 = -0.0;
1305 assert_eq!(0.0, neg_zero);
1306 assert!(!neg_zero.is_infinite());
1307 assert!(neg_zero.is_finite());
1308 assert!(!neg_zero.is_sign_positive());
1309 assert!(neg_zero.is_sign_negative());
1310 assert!(!neg_zero.is_nan());
1311 assert!(!neg_zero.is_normal());
1312 assert_eq!(Fp::Zero, neg_zero.classify());
1317 let one: f32 = 1.0f32;
1318 assert_eq!(1.0, one);
1319 assert!(!one.is_infinite());
1320 assert!(one.is_finite());
1321 assert!(one.is_sign_positive());
1322 assert!(!one.is_sign_negative());
1323 assert!(!one.is_nan());
1324 assert!(one.is_normal());
1325 assert_eq!(Fp::Normal, one.classify());
1330 let nan: f32 = f32::NAN;
1331 let inf: f32 = f32::INFINITY;
1332 let neg_inf: f32 = f32::NEG_INFINITY;
1333 assert!(nan.is_nan());
1334 assert!(!0.0f32.is_nan());
1335 assert!(!5.3f32.is_nan());
1336 assert!(!(-10.732f32).is_nan());
1337 assert!(!inf.is_nan());
1338 assert!(!neg_inf.is_nan());
1342 fn test_is_infinite() {
1343 let nan: f32 = f32::NAN;
1344 let inf: f32 = f32::INFINITY;
1345 let neg_inf: f32 = f32::NEG_INFINITY;
1346 assert!(!nan.is_infinite());
1347 assert!(inf.is_infinite());
1348 assert!(neg_inf.is_infinite());
1349 assert!(!0.0f32.is_infinite());
1350 assert!(!42.8f32.is_infinite());
1351 assert!(!(-109.2f32).is_infinite());
1355 fn test_is_finite() {
1356 let nan: f32 = f32::NAN;
1357 let inf: f32 = f32::INFINITY;
1358 let neg_inf: f32 = f32::NEG_INFINITY;
1359 assert!(!nan.is_finite());
1360 assert!(!inf.is_finite());
1361 assert!(!neg_inf.is_finite());
1362 assert!(0.0f32.is_finite());
1363 assert!(42.8f32.is_finite());
1364 assert!((-109.2f32).is_finite());
1368 fn test_is_normal() {
1369 let nan: f32 = f32::NAN;
1370 let inf: f32 = f32::INFINITY;
1371 let neg_inf: f32 = f32::NEG_INFINITY;
1372 let zero: f32 = 0.0f32;
1373 let neg_zero: f32 = -0.0;
1374 assert!(!nan.is_normal());
1375 assert!(!inf.is_normal());
1376 assert!(!neg_inf.is_normal());
1377 assert!(!zero.is_normal());
1378 assert!(!neg_zero.is_normal());
1379 assert!(1f32.is_normal());
1380 assert!(1e-37f32.is_normal());
1381 assert!(!1e-38f32.is_normal());
1385 fn test_classify() {
1386 let nan: f32 = f32::NAN;
1387 let inf: f32 = f32::INFINITY;
1388 let neg_inf: f32 = f32::NEG_INFINITY;
1389 let zero: f32 = 0.0f32;
1390 let neg_zero: f32 = -0.0;
1391 assert_eq!(nan.classify(), Fp::Nan);
1392 assert_eq!(inf.classify(), Fp::Infinite);
1393 assert_eq!(neg_inf.classify(), Fp::Infinite);
1394 assert_eq!(zero.classify(), Fp::Zero);
1395 assert_eq!(neg_zero.classify(), Fp::Zero);
1396 assert_eq!(1f32.classify(), Fp::Normal);
1397 assert_eq!(1e-37f32.classify(), Fp::Normal);
1398 assert_eq!(1e-38f32.classify(), Fp::Subnormal);
1402 #[allow(deprecated)]
1403 fn test_integer_decode() {
1404 assert_eq!(3.14159265359f32.integer_decode(), (13176795, -22, 1));
1405 assert_eq!((-8573.5918555f32).integer_decode(), (8779358, -10, -1));
1406 assert_eq!(2f32.powf(100.0).integer_decode(), (8388608, 77, 1));
1407 assert_eq!(0f32.integer_decode(), (0, -150, 1));
1408 assert_eq!((-0f32).integer_decode(), (0, -150, -1));
1409 assert_eq!(INFINITY.integer_decode(), (8388608, 105, 1));
1410 assert_eq!(NEG_INFINITY.integer_decode(), (8388608, 105, -1));
1412 // Ignore the "sign" (quiet / signalling flag) of NAN.
1413 // It can vary between runtime operations and LLVM folding.
1414 let (nan_m, nan_e, _nan_s) = NAN.integer_decode();
1415 assert_eq!((nan_m, nan_e), (12582912, 105));
1420 assert_approx_eq!(1.0f32.floor(), 1.0f32);
1421 assert_approx_eq!(1.3f32.floor(), 1.0f32);
1422 assert_approx_eq!(1.5f32.floor(), 1.0f32);
1423 assert_approx_eq!(1.7f32.floor(), 1.0f32);
1424 assert_approx_eq!(0.0f32.floor(), 0.0f32);
1425 assert_approx_eq!((-0.0f32).floor(), -0.0f32);
1426 assert_approx_eq!((-1.0f32).floor(), -1.0f32);
1427 assert_approx_eq!((-1.3f32).floor(), -2.0f32);
1428 assert_approx_eq!((-1.5f32).floor(), -2.0f32);
1429 assert_approx_eq!((-1.7f32).floor(), -2.0f32);
1434 assert_approx_eq!(1.0f32.ceil(), 1.0f32);
1435 assert_approx_eq!(1.3f32.ceil(), 2.0f32);
1436 assert_approx_eq!(1.5f32.ceil(), 2.0f32);
1437 assert_approx_eq!(1.7f32.ceil(), 2.0f32);
1438 assert_approx_eq!(0.0f32.ceil(), 0.0f32);
1439 assert_approx_eq!((-0.0f32).ceil(), -0.0f32);
1440 assert_approx_eq!((-1.0f32).ceil(), -1.0f32);
1441 assert_approx_eq!((-1.3f32).ceil(), -1.0f32);
1442 assert_approx_eq!((-1.5f32).ceil(), -1.0f32);
1443 assert_approx_eq!((-1.7f32).ceil(), -1.0f32);
1448 assert_approx_eq!(1.0f32.round(), 1.0f32);
1449 assert_approx_eq!(1.3f32.round(), 1.0f32);
1450 assert_approx_eq!(1.5f32.round(), 2.0f32);
1451 assert_approx_eq!(1.7f32.round(), 2.0f32);
1452 assert_approx_eq!(0.0f32.round(), 0.0f32);
1453 assert_approx_eq!((-0.0f32).round(), -0.0f32);
1454 assert_approx_eq!((-1.0f32).round(), -1.0f32);
1455 assert_approx_eq!((-1.3f32).round(), -1.0f32);
1456 assert_approx_eq!((-1.5f32).round(), -2.0f32);
1457 assert_approx_eq!((-1.7f32).round(), -2.0f32);
1462 assert_approx_eq!(1.0f32.trunc(), 1.0f32);
1463 assert_approx_eq!(1.3f32.trunc(), 1.0f32);
1464 assert_approx_eq!(1.5f32.trunc(), 1.0f32);
1465 assert_approx_eq!(1.7f32.trunc(), 1.0f32);
1466 assert_approx_eq!(0.0f32.trunc(), 0.0f32);
1467 assert_approx_eq!((-0.0f32).trunc(), -0.0f32);
1468 assert_approx_eq!((-1.0f32).trunc(), -1.0f32);
1469 assert_approx_eq!((-1.3f32).trunc(), -1.0f32);
1470 assert_approx_eq!((-1.5f32).trunc(), -1.0f32);
1471 assert_approx_eq!((-1.7f32).trunc(), -1.0f32);
1476 assert_approx_eq!(1.0f32.fract(), 0.0f32);
1477 assert_approx_eq!(1.3f32.fract(), 0.3f32);
1478 assert_approx_eq!(1.5f32.fract(), 0.5f32);
1479 assert_approx_eq!(1.7f32.fract(), 0.7f32);
1480 assert_approx_eq!(0.0f32.fract(), 0.0f32);
1481 assert_approx_eq!((-0.0f32).fract(), -0.0f32);
1482 assert_approx_eq!((-1.0f32).fract(), -0.0f32);
1483 assert_approx_eq!((-1.3f32).fract(), -0.3f32);
1484 assert_approx_eq!((-1.5f32).fract(), -0.5f32);
1485 assert_approx_eq!((-1.7f32).fract(), -0.7f32);
1490 assert_eq!(INFINITY.abs(), INFINITY);
1491 assert_eq!(1f32.abs(), 1f32);
1492 assert_eq!(0f32.abs(), 0f32);
1493 assert_eq!((-0f32).abs(), 0f32);
1494 assert_eq!((-1f32).abs(), 1f32);
1495 assert_eq!(NEG_INFINITY.abs(), INFINITY);
1496 assert_eq!((1f32/NEG_INFINITY).abs(), 0f32);
1497 assert!(NAN.abs().is_nan());
1502 assert_eq!(INFINITY.signum(), 1f32);
1503 assert_eq!(1f32.signum(), 1f32);
1504 assert_eq!(0f32.signum(), 1f32);
1505 assert_eq!((-0f32).signum(), -1f32);
1506 assert_eq!((-1f32).signum(), -1f32);
1507 assert_eq!(NEG_INFINITY.signum(), -1f32);
1508 assert_eq!((1f32/NEG_INFINITY).signum(), -1f32);
1509 assert!(NAN.signum().is_nan());
1513 fn test_is_sign_positive() {
1514 assert!(INFINITY.is_sign_positive());
1515 assert!(1f32.is_sign_positive());
1516 assert!(0f32.is_sign_positive());
1517 assert!(!(-0f32).is_sign_positive());
1518 assert!(!(-1f32).is_sign_positive());
1519 assert!(!NEG_INFINITY.is_sign_positive());
1520 assert!(!(1f32/NEG_INFINITY).is_sign_positive());
1521 assert!(!NAN.is_sign_positive());
1525 fn test_is_sign_negative() {
1526 assert!(!INFINITY.is_sign_negative());
1527 assert!(!1f32.is_sign_negative());
1528 assert!(!0f32.is_sign_negative());
1529 assert!((-0f32).is_sign_negative());
1530 assert!((-1f32).is_sign_negative());
1531 assert!(NEG_INFINITY.is_sign_negative());
1532 assert!((1f32/NEG_INFINITY).is_sign_negative());
1533 assert!(!NAN.is_sign_negative());
1538 let nan: f32 = f32::NAN;
1539 let inf: f32 = f32::INFINITY;
1540 let neg_inf: f32 = f32::NEG_INFINITY;
1541 assert_approx_eq!(12.3f32.mul_add(4.5, 6.7), 62.05);
1542 assert_approx_eq!((-12.3f32).mul_add(-4.5, -6.7), 48.65);
1543 assert_approx_eq!(0.0f32.mul_add(8.9, 1.2), 1.2);
1544 assert_approx_eq!(3.4f32.mul_add(-0.0, 5.6), 5.6);
1545 assert!(nan.mul_add(7.8, 9.0).is_nan());
1546 assert_eq!(inf.mul_add(7.8, 9.0), inf);
1547 assert_eq!(neg_inf.mul_add(7.8, 9.0), neg_inf);
1548 assert_eq!(8.9f32.mul_add(inf, 3.2), inf);
1549 assert_eq!((-3.2f32).mul_add(2.4, neg_inf), neg_inf);
1554 let nan: f32 = f32::NAN;
1555 let inf: f32 = f32::INFINITY;
1556 let neg_inf: f32 = f32::NEG_INFINITY;
1557 assert_eq!(1.0f32.recip(), 1.0);
1558 assert_eq!(2.0f32.recip(), 0.5);
1559 assert_eq!((-0.4f32).recip(), -2.5);
1560 assert_eq!(0.0f32.recip(), inf);
1561 assert!(nan.recip().is_nan());
1562 assert_eq!(inf.recip(), 0.0);
1563 assert_eq!(neg_inf.recip(), 0.0);
1568 let nan: f32 = f32::NAN;
1569 let inf: f32 = f32::INFINITY;
1570 let neg_inf: f32 = f32::NEG_INFINITY;
1571 assert_eq!(1.0f32.powi(1), 1.0);
1572 assert_approx_eq!((-3.1f32).powi(2), 9.61);
1573 assert_approx_eq!(5.9f32.powi(-2), 0.028727);
1574 assert_eq!(8.3f32.powi(0), 1.0);
1575 assert!(nan.powi(2).is_nan());
1576 assert_eq!(inf.powi(3), inf);
1577 assert_eq!(neg_inf.powi(2), inf);
1582 let nan: f32 = f32::NAN;
1583 let inf: f32 = f32::INFINITY;
1584 let neg_inf: f32 = f32::NEG_INFINITY;
1585 assert_eq!(1.0f32.powf(1.0), 1.0);
1586 assert_approx_eq!(3.4f32.powf(4.5), 246.408218);
1587 assert_approx_eq!(2.7f32.powf(-3.2), 0.041652);
1588 assert_approx_eq!((-3.1f32).powf(2.0), 9.61);
1589 assert_approx_eq!(5.9f32.powf(-2.0), 0.028727);
1590 assert_eq!(8.3f32.powf(0.0), 1.0);
1591 assert!(nan.powf(2.0).is_nan());
1592 assert_eq!(inf.powf(2.0), inf);
1593 assert_eq!(neg_inf.powf(3.0), neg_inf);
1597 fn test_sqrt_domain() {
1598 assert!(NAN.sqrt().is_nan());
1599 assert!(NEG_INFINITY.sqrt().is_nan());
1600 assert!((-1.0f32).sqrt().is_nan());
1601 assert_eq!((-0.0f32).sqrt(), -0.0);
1602 assert_eq!(0.0f32.sqrt(), 0.0);
1603 assert_eq!(1.0f32.sqrt(), 1.0);
1604 assert_eq!(INFINITY.sqrt(), INFINITY);
1609 assert_eq!(1.0, 0.0f32.exp());
1610 assert_approx_eq!(2.718282, 1.0f32.exp());
1611 assert_approx_eq!(148.413162, 5.0f32.exp());
1613 let inf: f32 = f32::INFINITY;
1614 let neg_inf: f32 = f32::NEG_INFINITY;
1615 let nan: f32 = f32::NAN;
1616 assert_eq!(inf, inf.exp());
1617 assert_eq!(0.0, neg_inf.exp());
1618 assert!(nan.exp().is_nan());
1623 assert_eq!(32.0, 5.0f32.exp2());
1624 assert_eq!(1.0, 0.0f32.exp2());
1626 let inf: f32 = f32::INFINITY;
1627 let neg_inf: f32 = f32::NEG_INFINITY;
1628 let nan: f32 = f32::NAN;
1629 assert_eq!(inf, inf.exp2());
1630 assert_eq!(0.0, neg_inf.exp2());
1631 assert!(nan.exp2().is_nan());
1636 let nan: f32 = f32::NAN;
1637 let inf: f32 = f32::INFINITY;
1638 let neg_inf: f32 = f32::NEG_INFINITY;
1639 assert_approx_eq!(1.0f32.exp().ln(), 1.0);
1640 assert!(nan.ln().is_nan());
1641 assert_eq!(inf.ln(), inf);
1642 assert!(neg_inf.ln().is_nan());
1643 assert!((-2.3f32).ln().is_nan());
1644 assert_eq!((-0.0f32).ln(), neg_inf);
1645 assert_eq!(0.0f32.ln(), neg_inf);
1646 assert_approx_eq!(4.0f32.ln(), 1.386294);
1651 let nan: f32 = f32::NAN;
1652 let inf: f32 = f32::INFINITY;
1653 let neg_inf: f32 = f32::NEG_INFINITY;
1654 assert_eq!(10.0f32.log(10.0), 1.0);
1655 assert_approx_eq!(2.3f32.log(3.5), 0.664858);
1656 assert_eq!(1.0f32.exp().log(1.0f32.exp()), 1.0);
1657 assert!(1.0f32.log(1.0).is_nan());
1658 assert!(1.0f32.log(-13.9).is_nan());
1659 assert!(nan.log(2.3).is_nan());
1660 assert_eq!(inf.log(10.0), inf);
1661 assert!(neg_inf.log(8.8).is_nan());
1662 assert!((-2.3f32).log(0.1).is_nan());
1663 assert_eq!((-0.0f32).log(2.0), neg_inf);
1664 assert_eq!(0.0f32.log(7.0), neg_inf);
1669 let nan: f32 = f32::NAN;
1670 let inf: f32 = f32::INFINITY;
1671 let neg_inf: f32 = f32::NEG_INFINITY;
1672 assert_approx_eq!(10.0f32.log2(), 3.321928);
1673 assert_approx_eq!(2.3f32.log2(), 1.201634);
1674 assert_approx_eq!(1.0f32.exp().log2(), 1.442695);
1675 assert!(nan.log2().is_nan());
1676 assert_eq!(inf.log2(), inf);
1677 assert!(neg_inf.log2().is_nan());
1678 assert!((-2.3f32).log2().is_nan());
1679 assert_eq!((-0.0f32).log2(), neg_inf);
1680 assert_eq!(0.0f32.log2(), neg_inf);
1685 let nan: f32 = f32::NAN;
1686 let inf: f32 = f32::INFINITY;
1687 let neg_inf: f32 = f32::NEG_INFINITY;
1688 assert_eq!(10.0f32.log10(), 1.0);
1689 assert_approx_eq!(2.3f32.log10(), 0.361728);
1690 assert_approx_eq!(1.0f32.exp().log10(), 0.434294);
1691 assert_eq!(1.0f32.log10(), 0.0);
1692 assert!(nan.log10().is_nan());
1693 assert_eq!(inf.log10(), inf);
1694 assert!(neg_inf.log10().is_nan());
1695 assert!((-2.3f32).log10().is_nan());
1696 assert_eq!((-0.0f32).log10(), neg_inf);
1697 assert_eq!(0.0f32.log10(), neg_inf);
1701 fn test_to_degrees() {
1702 let pi: f32 = consts::PI;
1703 let nan: f32 = f32::NAN;
1704 let inf: f32 = f32::INFINITY;
1705 let neg_inf: f32 = f32::NEG_INFINITY;
1706 assert_eq!(0.0f32.to_degrees(), 0.0);
1707 assert_approx_eq!((-5.8f32).to_degrees(), -332.315521);
1708 assert_eq!(pi.to_degrees(), 180.0);
1709 assert!(nan.to_degrees().is_nan());
1710 assert_eq!(inf.to_degrees(), inf);
1711 assert_eq!(neg_inf.to_degrees(), neg_inf);
1715 fn test_to_radians() {
1716 let pi: f32 = consts::PI;
1717 let nan: f32 = f32::NAN;
1718 let inf: f32 = f32::INFINITY;
1719 let neg_inf: f32 = f32::NEG_INFINITY;
1720 assert_eq!(0.0f32.to_radians(), 0.0);
1721 assert_approx_eq!(154.6f32.to_radians(), 2.698279);
1722 assert_approx_eq!((-332.31f32).to_radians(), -5.799903);
1723 assert_eq!(180.0f32.to_radians(), pi);
1724 assert!(nan.to_radians().is_nan());
1725 assert_eq!(inf.to_radians(), inf);
1726 assert_eq!(neg_inf.to_radians(), neg_inf);
1730 #[allow(deprecated)]
1732 let f1 = 2.0f32.powi(-123);
1733 let f2 = 2.0f32.powi(-111);
1734 let f3 = 1.75 * 2.0f32.powi(-12);
1735 assert_eq!(f32::ldexp(1f32, -123), f1);
1736 assert_eq!(f32::ldexp(1f32, -111), f2);
1737 assert_eq!(f32::ldexp(1.75f32, -12), f3);
1739 assert_eq!(f32::ldexp(0f32, -123), 0f32);
1740 assert_eq!(f32::ldexp(-0f32, -123), -0f32);
1742 let inf: f32 = f32::INFINITY;
1743 let neg_inf: f32 = f32::NEG_INFINITY;
1744 let nan: f32 = f32::NAN;
1745 assert_eq!(f32::ldexp(inf, -123), inf);
1746 assert_eq!(f32::ldexp(neg_inf, -123), neg_inf);
1747 assert!(f32::ldexp(nan, -123).is_nan());
1751 #[allow(deprecated)]
1753 let f1 = 2.0f32.powi(-123);
1754 let f2 = 2.0f32.powi(-111);
1755 let f3 = 1.75 * 2.0f32.powi(-123);
1756 let (x1, exp1) = f1.frexp();
1757 let (x2, exp2) = f2.frexp();
1758 let (x3, exp3) = f3.frexp();
1759 assert_eq!((x1, exp1), (0.5f32, -122));
1760 assert_eq!((x2, exp2), (0.5f32, -110));
1761 assert_eq!((x3, exp3), (0.875f32, -122));
1762 assert_eq!(f32::ldexp(x1, exp1), f1);
1763 assert_eq!(f32::ldexp(x2, exp2), f2);
1764 assert_eq!(f32::ldexp(x3, exp3), f3);
1766 assert_eq!(0f32.frexp(), (0f32, 0));
1767 assert_eq!((-0f32).frexp(), (-0f32, 0));
1770 #[test] #[cfg_attr(windows, ignore)] // FIXME #8755
1771 #[allow(deprecated)]
1772 fn test_frexp_nowin() {
1773 let inf: f32 = f32::INFINITY;
1774 let neg_inf: f32 = f32::NEG_INFINITY;
1775 let nan: f32 = f32::NAN;
1776 assert_eq!(match inf.frexp() { (x, _) => x }, inf);
1777 assert_eq!(match neg_inf.frexp() { (x, _) => x }, neg_inf);
1778 assert!(match nan.frexp() { (x, _) => x.is_nan() })
1783 assert_eq!(0.0f32.asinh(), 0.0f32);
1784 assert_eq!((-0.0f32).asinh(), -0.0f32);
1786 let inf: f32 = f32::INFINITY;
1787 let neg_inf: f32 = f32::NEG_INFINITY;
1788 let nan: f32 = f32::NAN;
1789 assert_eq!(inf.asinh(), inf);
1790 assert_eq!(neg_inf.asinh(), neg_inf);
1791 assert!(nan.asinh().is_nan());
1792 assert_approx_eq!(2.0f32.asinh(), 1.443635475178810342493276740273105f32);
1793 assert_approx_eq!((-2.0f32).asinh(), -1.443635475178810342493276740273105f32);
1798 assert_eq!(1.0f32.acosh(), 0.0f32);
1799 assert!(0.999f32.acosh().is_nan());
1801 let inf: f32 = f32::INFINITY;
1802 let neg_inf: f32 = f32::NEG_INFINITY;
1803 let nan: f32 = f32::NAN;
1804 assert_eq!(inf.acosh(), inf);
1805 assert!(neg_inf.acosh().is_nan());
1806 assert!(nan.acosh().is_nan());
1807 assert_approx_eq!(2.0f32.acosh(), 1.31695789692481670862504634730796844f32);
1808 assert_approx_eq!(3.0f32.acosh(), 1.76274717403908605046521864995958461f32);
1813 assert_eq!(0.0f32.atanh(), 0.0f32);
1814 assert_eq!((-0.0f32).atanh(), -0.0f32);
1816 let inf32: f32 = f32::INFINITY;
1817 let neg_inf32: f32 = f32::NEG_INFINITY;
1818 assert_eq!(1.0f32.atanh(), inf32);
1819 assert_eq!((-1.0f32).atanh(), neg_inf32);
1821 assert!(2f64.atanh().atanh().is_nan());
1822 assert!((-2f64).atanh().atanh().is_nan());
1824 let inf64: f32 = f32::INFINITY;
1825 let neg_inf64: f32 = f32::NEG_INFINITY;
1826 let nan32: f32 = f32::NAN;
1827 assert!(inf64.atanh().is_nan());
1828 assert!(neg_inf64.atanh().is_nan());
1829 assert!(nan32.atanh().is_nan());
1831 assert_approx_eq!(0.5f32.atanh(), 0.54930614433405484569762261846126285f32);
1832 assert_approx_eq!((-0.5f32).atanh(), -0.54930614433405484569762261846126285f32);
1836 fn test_real_consts() {
1839 let pi: f32 = consts::PI;
1840 let frac_pi_2: f32 = consts::FRAC_PI_2;
1841 let frac_pi_3: f32 = consts::FRAC_PI_3;
1842 let frac_pi_4: f32 = consts::FRAC_PI_4;
1843 let frac_pi_6: f32 = consts::FRAC_PI_6;
1844 let frac_pi_8: f32 = consts::FRAC_PI_8;
1845 let frac_1_pi: f32 = consts::FRAC_1_PI;
1846 let frac_2_pi: f32 = consts::FRAC_2_PI;
1847 let frac_2_sqrtpi: f32 = consts::FRAC_2_SQRT_PI;
1848 let sqrt2: f32 = consts::SQRT_2;
1849 let frac_1_sqrt2: f32 = consts::FRAC_1_SQRT_2;
1850 let e: f32 = consts::E;
1851 let log2_e: f32 = consts::LOG2_E;
1852 let log10_e: f32 = consts::LOG10_E;
1853 let ln_2: f32 = consts::LN_2;
1854 let ln_10: f32 = consts::LN_10;
1856 assert_approx_eq!(frac_pi_2, pi / 2f32);
1857 assert_approx_eq!(frac_pi_3, pi / 3f32);
1858 assert_approx_eq!(frac_pi_4, pi / 4f32);
1859 assert_approx_eq!(frac_pi_6, pi / 6f32);
1860 assert_approx_eq!(frac_pi_8, pi / 8f32);
1861 assert_approx_eq!(frac_1_pi, 1f32 / pi);
1862 assert_approx_eq!(frac_2_pi, 2f32 / pi);
1863 assert_approx_eq!(frac_2_sqrtpi, 2f32 / pi.sqrt());
1864 assert_approx_eq!(sqrt2, 2f32.sqrt());
1865 assert_approx_eq!(frac_1_sqrt2, 1f32 / 2f32.sqrt());
1866 assert_approx_eq!(log2_e, e.log2());
1867 assert_approx_eq!(log10_e, e.log10());
1868 assert_approx_eq!(ln_2, 2f32.ln());
1869 assert_approx_eq!(ln_10, 10f32.ln());