// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Operations and constants for 32-bits floats (`f32` type) #![stable] #![allow(missing_docs)] #![allow(unsigned_negation)] #![doc(primitive = "f32")] use prelude::v1::*; use intrinsics; use libc::c_int; use num::{Float, FpCategory}; use num::strconv; use num::strconv::ExponentFormat::{ExpNone, ExpDec}; use num::strconv::SignificantDigits::{DigAll, DigMax, DigExact}; use num::strconv::SignFormat::SignNeg; use core::num; pub use core::f32::{RADIX, MANTISSA_DIGITS, DIGITS, EPSILON, MIN_VALUE}; pub use core::f32::{MIN_POS_VALUE, MAX_VALUE, MIN_EXP, MAX_EXP, MIN_10_EXP}; pub use core::f32::{MAX_10_EXP, NAN, INFINITY, NEG_INFINITY}; pub use core::f32::consts; #[allow(dead_code)] mod cmath { use libc::{c_float, c_int}; #[link_name = "m"] extern { pub fn acosf(n: c_float) -> c_float; pub fn asinf(n: c_float) -> c_float; pub fn atanf(n: c_float) -> c_float; pub fn atan2f(a: c_float, b: c_float) -> c_float; pub fn cbrtf(n: c_float) -> c_float; pub fn coshf(n: c_float) -> c_float; pub fn erff(n: c_float) -> c_float; pub fn erfcf(n: c_float) -> c_float; pub fn expm1f(n: c_float) -> c_float; pub fn fdimf(a: c_float, b: c_float) -> c_float; pub fn frexpf(n: c_float, value: &mut c_int) -> c_float; pub fn fmaxf(a: c_float, b: c_float) -> c_float; pub fn fminf(a: c_float, b: c_float) -> c_float; pub fn fmodf(a: c_float, b: c_float) -> c_float; pub fn nextafterf(x: c_float, y: c_float) -> c_float; pub fn hypotf(x: c_float, y: c_float) -> c_float; pub fn ldexpf(x: c_float, n: c_int) -> c_float; pub fn logbf(n: c_float) -> c_float; pub fn log1pf(n: c_float) -> c_float; pub fn ilogbf(n: c_float) -> c_int; pub fn modff(n: c_float, iptr: &mut c_float) -> c_float; pub fn sinhf(n: c_float) -> c_float; pub fn tanf(n: c_float) -> c_float; pub fn tanhf(n: c_float) -> c_float; pub fn tgammaf(n: c_float) -> c_float; #[cfg(unix)] pub fn lgammaf_r(n: c_float, sign: &mut c_int) -> c_float; #[cfg(windows)] #[link_name="__lgammaf_r"] pub fn lgammaf_r(n: c_float, sign: &mut c_int) -> c_float; } } #[stable] impl Float for f32 { #[inline] fn nan() -> f32 { num::Float::nan() } #[inline] fn infinity() -> f32 { num::Float::infinity() } #[inline] fn neg_infinity() -> f32 { num::Float::neg_infinity() } #[inline] fn zero() -> f32 { num::Float::zero() } #[inline] fn neg_zero() -> f32 { num::Float::neg_zero() } #[inline] fn one() -> f32 { num::Float::one() } #[allow(deprecated)] #[inline] fn mantissa_digits(unused_self: Option) -> uint { num::Float::mantissa_digits(unused_self) } #[allow(deprecated)] #[inline] fn digits(unused_self: Option) -> uint { num::Float::digits(unused_self) } #[allow(deprecated)] #[inline] fn epsilon() -> f32 { num::Float::epsilon() } #[allow(deprecated)] #[inline] fn min_exp(unused_self: Option) -> int { num::Float::min_exp(unused_self) } #[allow(deprecated)] #[inline] fn max_exp(unused_self: Option) -> int { num::Float::max_exp(unused_self) } #[allow(deprecated)] #[inline] fn min_10_exp(unused_self: Option) -> int { num::Float::min_10_exp(unused_self) } #[allow(deprecated)] #[inline] fn max_10_exp(unused_self: Option) -> int { num::Float::max_10_exp(unused_self) } #[allow(deprecated)] #[inline] fn min_value() -> f32 { num::Float::min_value() } #[allow(deprecated)] #[inline] fn min_pos_value(unused_self: Option) -> f32 { num::Float::min_pos_value(unused_self) } #[allow(deprecated)] #[inline] fn max_value() -> f32 { num::Float::max_value() } #[inline] fn is_nan(self) -> bool { num::Float::is_nan(self) } #[inline] fn is_infinite(self) -> bool { num::Float::is_infinite(self) } #[inline] fn is_finite(self) -> bool { num::Float::is_finite(self) } #[inline] fn is_normal(self) -> bool { num::Float::is_normal(self) } #[inline] fn classify(self) -> FpCategory { num::Float::classify(self) } #[inline] fn integer_decode(self) -> (u64, i16, i8) { num::Float::integer_decode(self) } #[inline] fn floor(self) -> f32 { num::Float::floor(self) } #[inline] fn ceil(self) -> f32 { num::Float::ceil(self) } #[inline] fn round(self) -> f32 { num::Float::round(self) } #[inline] fn trunc(self) -> f32 { num::Float::trunc(self) } #[inline] fn fract(self) -> f32 { num::Float::fract(self) } #[inline] fn abs(self) -> f32 { num::Float::abs(self) } #[inline] fn signum(self) -> f32 { num::Float::signum(self) } #[inline] fn is_positive(self) -> bool { num::Float::is_positive(self) } #[inline] fn is_negative(self) -> bool { num::Float::is_negative(self) } #[inline] fn mul_add(self, a: f32, b: f32) -> f32 { num::Float::mul_add(self, a, b) } #[inline] fn recip(self) -> f32 { num::Float::recip(self) } #[inline] fn powi(self, n: i32) -> f32 { num::Float::powi(self, n) } #[inline] fn powf(self, n: f32) -> f32 { num::Float::powf(self, n) } #[inline] fn sqrt(self) -> f32 { num::Float::sqrt(self) } #[inline] fn rsqrt(self) -> f32 { num::Float::rsqrt(self) } #[inline] fn exp(self) -> f32 { num::Float::exp(self) } #[inline] fn exp2(self) -> f32 { num::Float::exp(self) } #[inline] fn ln(self) -> f32 { num::Float::ln(self) } #[inline] fn log(self, base: f32) -> f32 { num::Float::log(self, base) } #[inline] fn log2(self) -> f32 { num::Float::log2(self) } #[inline] fn log10(self) -> f32 { num::Float::log10(self) } #[inline] fn to_degrees(self) -> f32 { num::Float::to_degrees(self) } #[inline] fn to_radians(self) -> f32 { num::Float::to_radians(self) } /// Constructs a floating point number by multiplying `x` by 2 raised to the /// power of `exp` #[inline] fn ldexp(x: f32, exp: int) -> f32 { unsafe { cmath::ldexpf(x, exp as c_int) } } /// Breaks the number into a normalized fraction and a base-2 exponent, /// satisfying: /// /// - `self = x * pow(2, exp)` /// - `0.5 <= abs(x) < 1.0` #[inline] fn frexp(self) -> (f32, int) { unsafe { let mut exp = 0; let x = cmath::frexpf(self, &mut exp); (x, exp as int) } } /// Returns the next representable floating-point value in the direction of /// `other`. #[inline] fn next_after(self, other: f32) -> f32 { unsafe { cmath::nextafterf(self, other) } } #[inline] fn max(self, other: f32) -> f32 { unsafe { cmath::fmaxf(self, other) } } #[inline] fn min(self, other: f32) -> f32 { unsafe { cmath::fminf(self, other) } } #[inline] fn abs_sub(self, other: f32) -> f32 { unsafe { cmath::fdimf(self, other) } } #[inline] fn cbrt(self) -> f32 { unsafe { cmath::cbrtf(self) } } #[inline] fn hypot(self, other: f32) -> f32 { unsafe { cmath::hypotf(self, other) } } #[inline] fn sin(self) -> f32 { unsafe { intrinsics::sinf32(self) } } #[inline] fn cos(self) -> f32 { unsafe { intrinsics::cosf32(self) } } #[inline] fn tan(self) -> f32 { unsafe { cmath::tanf(self) } } #[inline] fn asin(self) -> f32 { unsafe { cmath::asinf(self) } } #[inline] fn acos(self) -> f32 { unsafe { cmath::acosf(self) } } #[inline] fn atan(self) -> f32 { unsafe { cmath::atanf(self) } } #[inline] fn atan2(self, other: f32) -> f32 { unsafe { cmath::atan2f(self, other) } } /// Simultaneously computes the sine and cosine of the number #[inline] fn sin_cos(self) -> (f32, f32) { (self.sin(), self.cos()) } /// Returns the exponential of the number, minus `1`, in a way that is /// accurate even if the number is close to zero #[inline] fn exp_m1(self) -> f32 { unsafe { cmath::expm1f(self) } } /// Returns the natural logarithm of the number plus `1` (`ln(1+n)`) more /// accurately than if the operations were performed separately #[inline] fn ln_1p(self) -> f32 { unsafe { cmath::log1pf(self) } } #[inline] fn sinh(self) -> f32 { unsafe { cmath::sinhf(self) } } #[inline] fn cosh(self) -> f32 { unsafe { cmath::coshf(self) } } #[inline] fn tanh(self) -> f32 { unsafe { cmath::tanhf(self) } } /// Inverse hyperbolic sine /// /// # Returns /// /// - on success, the inverse hyperbolic sine of `self` will be returned /// - `self` if `self` is `0.0`, `-0.0`, `INFINITY`, or `NEG_INFINITY` /// - `NAN` if `self` is `NAN` #[inline] fn asinh(self) -> f32 { match self { NEG_INFINITY => NEG_INFINITY, x => (x + ((x * x) + 1.0).sqrt()).ln(), } } /// Inverse hyperbolic cosine /// /// # Returns /// /// - on success, the inverse hyperbolic cosine of `self` will be returned /// - `INFINITY` if `self` is `INFINITY` /// - `NAN` if `self` is `NAN` or `self < 1.0` (including `NEG_INFINITY`) #[inline] fn acosh(self) -> f32 { match self { x if x < 1.0 => Float::nan(), x => (x + ((x * x) - 1.0).sqrt()).ln(), } } /// Inverse hyperbolic tangent /// /// # Returns /// /// - on success, the inverse hyperbolic tangent of `self` will be returned /// - `self` if `self` is `0.0` or `-0.0` /// - `INFINITY` if `self` is `1.0` /// - `NEG_INFINITY` if `self` is `-1.0` /// - `NAN` if the `self` is `NAN` or outside the domain of `-1.0 <= self <= 1.0` /// (including `INFINITY` and `NEG_INFINITY`) #[inline] fn atanh(self) -> f32 { 0.5 * ((2.0 * self) / (1.0 - self)).ln_1p() } } // // Section: String Conversions // /// Converts a float to a string /// /// # Arguments /// /// * num - The float value #[inline] #[experimental = "may be removed or relocated"] pub fn to_string(num: f32) -> String { let (r, _) = strconv::float_to_str_common( num, 10u, true, SignNeg, DigAll, ExpNone, false); r } /// Converts a float to a string in hexadecimal format /// /// # Arguments /// /// * num - The float value #[inline] #[experimental = "may be removed or relocated"] pub fn to_str_hex(num: f32) -> String { let (r, _) = strconv::float_to_str_common( num, 16u, true, SignNeg, DigAll, ExpNone, false); r } /// Converts a float to a string in a given radix, and a flag indicating /// whether it's a special value /// /// # Arguments /// /// * num - The float value /// * radix - The base to use #[inline] #[experimental = "may be removed or relocated"] pub fn to_str_radix_special(num: f32, rdx: uint) -> (String, bool) { strconv::float_to_str_common(num, rdx, true, SignNeg, DigAll, ExpNone, false) } /// Converts a float to a string with exactly the number of /// provided significant digits /// /// # Arguments /// /// * num - The float value /// * digits - The number of significant digits #[inline] #[experimental = "may be removed or relocated"] pub fn to_str_exact(num: f32, dig: uint) -> String { let (r, _) = strconv::float_to_str_common( num, 10u, true, SignNeg, DigExact(dig), ExpNone, false); r } /// Converts a float to a string with a maximum number of /// significant digits /// /// # Arguments /// /// * num - The float value /// * digits - The number of significant digits #[inline] #[experimental = "may be removed or relocated"] pub fn to_str_digits(num: f32, dig: uint) -> String { let (r, _) = strconv::float_to_str_common( num, 10u, true, SignNeg, DigMax(dig), ExpNone, false); r } /// Converts a float to a string using the exponential notation with exactly the number of /// provided digits after the decimal point in the significand /// /// # Arguments /// /// * num - The float value /// * digits - The number of digits after the decimal point /// * upper - Use `E` instead of `e` for the exponent sign #[inline] #[experimental = "may be removed or relocated"] pub fn to_str_exp_exact(num: f32, dig: uint, upper: bool) -> String { let (r, _) = strconv::float_to_str_common( num, 10u, true, SignNeg, DigExact(dig), ExpDec, upper); r } /// Converts a float to a string using the exponential notation with the maximum number of /// digits after the decimal point in the significand /// /// # Arguments /// /// * num - The float value /// * digits - The number of digits after the decimal point /// * upper - Use `E` instead of `e` for the exponent sign #[inline] #[experimental = "may be removed or relocated"] pub fn to_str_exp_digits(num: f32, dig: uint, upper: bool) -> String { let (r, _) = strconv::float_to_str_common( num, 10u, true, SignNeg, DigMax(dig), ExpDec, upper); r } #[cfg(test)] mod tests { use f32::*; use num::*; use num::FpCategory as Fp; #[test] fn test_min_nan() { assert_eq!(NAN.min(2.0), 2.0); assert_eq!(2.0f32.min(NAN), 2.0); } #[test] fn test_max_nan() { assert_eq!(NAN.max(2.0), 2.0); assert_eq!(2.0f32.max(NAN), 2.0); } #[test] fn test_num_f32() { test_num(10f32, 2f32); } #[test] fn test_floor() { assert_approx_eq!(1.0f32.floor(), 1.0f32); assert_approx_eq!(1.3f32.floor(), 1.0f32); assert_approx_eq!(1.5f32.floor(), 1.0f32); assert_approx_eq!(1.7f32.floor(), 1.0f32); assert_approx_eq!(0.0f32.floor(), 0.0f32); assert_approx_eq!((-0.0f32).floor(), -0.0f32); assert_approx_eq!((-1.0f32).floor(), -1.0f32); assert_approx_eq!((-1.3f32).floor(), -2.0f32); assert_approx_eq!((-1.5f32).floor(), -2.0f32); assert_approx_eq!((-1.7f32).floor(), -2.0f32); } #[test] fn test_ceil() { assert_approx_eq!(1.0f32.ceil(), 1.0f32); assert_approx_eq!(1.3f32.ceil(), 2.0f32); assert_approx_eq!(1.5f32.ceil(), 2.0f32); assert_approx_eq!(1.7f32.ceil(), 2.0f32); assert_approx_eq!(0.0f32.ceil(), 0.0f32); assert_approx_eq!((-0.0f32).ceil(), -0.0f32); assert_approx_eq!((-1.0f32).ceil(), -1.0f32); assert_approx_eq!((-1.3f32).ceil(), -1.0f32); assert_approx_eq!((-1.5f32).ceil(), -1.0f32); assert_approx_eq!((-1.7f32).ceil(), -1.0f32); } #[test] fn test_round() { assert_approx_eq!(1.0f32.round(), 1.0f32); assert_approx_eq!(1.3f32.round(), 1.0f32); assert_approx_eq!(1.5f32.round(), 2.0f32); assert_approx_eq!(1.7f32.round(), 2.0f32); assert_approx_eq!(0.0f32.round(), 0.0f32); assert_approx_eq!((-0.0f32).round(), -0.0f32); assert_approx_eq!((-1.0f32).round(), -1.0f32); assert_approx_eq!((-1.3f32).round(), -1.0f32); assert_approx_eq!((-1.5f32).round(), -2.0f32); assert_approx_eq!((-1.7f32).round(), -2.0f32); } #[test] fn test_trunc() { assert_approx_eq!(1.0f32.trunc(), 1.0f32); assert_approx_eq!(1.3f32.trunc(), 1.0f32); assert_approx_eq!(1.5f32.trunc(), 1.0f32); assert_approx_eq!(1.7f32.trunc(), 1.0f32); assert_approx_eq!(0.0f32.trunc(), 0.0f32); assert_approx_eq!((-0.0f32).trunc(), -0.0f32); assert_approx_eq!((-1.0f32).trunc(), -1.0f32); assert_approx_eq!((-1.3f32).trunc(), -1.0f32); assert_approx_eq!((-1.5f32).trunc(), -1.0f32); assert_approx_eq!((-1.7f32).trunc(), -1.0f32); } #[test] fn test_fract() { assert_approx_eq!(1.0f32.fract(), 0.0f32); assert_approx_eq!(1.3f32.fract(), 0.3f32); assert_approx_eq!(1.5f32.fract(), 0.5f32); assert_approx_eq!(1.7f32.fract(), 0.7f32); assert_approx_eq!(0.0f32.fract(), 0.0f32); assert_approx_eq!((-0.0f32).fract(), -0.0f32); assert_approx_eq!((-1.0f32).fract(), -0.0f32); assert_approx_eq!((-1.3f32).fract(), -0.3f32); assert_approx_eq!((-1.5f32).fract(), -0.5f32); assert_approx_eq!((-1.7f32).fract(), -0.7f32); } #[test] fn test_asinh() { assert_eq!(0.0f32.asinh(), 0.0f32); assert_eq!((-0.0f32).asinh(), -0.0f32); let inf: f32 = Float::infinity(); let neg_inf: f32 = Float::neg_infinity(); let nan: f32 = Float::nan(); assert_eq!(inf.asinh(), inf); assert_eq!(neg_inf.asinh(), neg_inf); assert!(nan.asinh().is_nan()); assert_approx_eq!(2.0f32.asinh(), 1.443635475178810342493276740273105f32); assert_approx_eq!((-2.0f32).asinh(), -1.443635475178810342493276740273105f32); } #[test] fn test_acosh() { assert_eq!(1.0f32.acosh(), 0.0f32); assert!(0.999f32.acosh().is_nan()); let inf: f32 = Float::infinity(); let neg_inf: f32 = Float::neg_infinity(); let nan: f32 = Float::nan(); assert_eq!(inf.acosh(), inf); assert!(neg_inf.acosh().is_nan()); assert!(nan.acosh().is_nan()); assert_approx_eq!(2.0f32.acosh(), 1.31695789692481670862504634730796844f32); assert_approx_eq!(3.0f32.acosh(), 1.76274717403908605046521864995958461f32); } #[test] fn test_atanh() { assert_eq!(0.0f32.atanh(), 0.0f32); assert_eq!((-0.0f32).atanh(), -0.0f32); let inf32: f32 = Float::infinity(); let neg_inf32: f32 = Float::neg_infinity(); assert_eq!(1.0f32.atanh(), inf32); assert_eq!((-1.0f32).atanh(), neg_inf32); assert!(2f64.atanh().atanh().is_nan()); assert!((-2f64).atanh().atanh().is_nan()); let inf64: f32 = Float::infinity(); let neg_inf64: f32 = Float::neg_infinity(); let nan32: f32 = Float::nan(); assert!(inf64.atanh().is_nan()); assert!(neg_inf64.atanh().is_nan()); assert!(nan32.atanh().is_nan()); assert_approx_eq!(0.5f32.atanh(), 0.54930614433405484569762261846126285f32); assert_approx_eq!((-0.5f32).atanh(), -0.54930614433405484569762261846126285f32); } #[test] fn test_real_consts() { use super::consts; let pi: f32 = consts::PI; let two_pi: f32 = consts::PI_2; let frac_pi_2: f32 = consts::FRAC_PI_2; let frac_pi_3: f32 = consts::FRAC_PI_3; let frac_pi_4: f32 = consts::FRAC_PI_4; let frac_pi_6: f32 = consts::FRAC_PI_6; let frac_pi_8: f32 = consts::FRAC_PI_8; let frac_1_pi: f32 = consts::FRAC_1_PI; let frac_2_pi: f32 = consts::FRAC_2_PI; let frac_2_sqrtpi: f32 = consts::FRAC_2_SQRTPI; let sqrt2: f32 = consts::SQRT2; let frac_1_sqrt2: f32 = consts::FRAC_1_SQRT2; let e: f32 = consts::E; let log2_e: f32 = consts::LOG2_E; let log10_e: f32 = consts::LOG10_E; let ln_2: f32 = consts::LN_2; let ln_10: f32 = consts::LN_10; assert_approx_eq!(two_pi, 2f32 * pi); assert_approx_eq!(frac_pi_2, pi / 2f32); assert_approx_eq!(frac_pi_3, pi / 3f32); assert_approx_eq!(frac_pi_4, pi / 4f32); assert_approx_eq!(frac_pi_6, pi / 6f32); assert_approx_eq!(frac_pi_8, pi / 8f32); assert_approx_eq!(frac_1_pi, 1f32 / pi); assert_approx_eq!(frac_2_pi, 2f32 / pi); assert_approx_eq!(frac_2_sqrtpi, 2f32 / pi.sqrt()); assert_approx_eq!(sqrt2, 2f32.sqrt()); assert_approx_eq!(frac_1_sqrt2, 1f32 / 2f32.sqrt()); assert_approx_eq!(log2_e, e.log2()); assert_approx_eq!(log10_e, e.log10()); assert_approx_eq!(ln_2, 2f32.ln()); assert_approx_eq!(ln_10, 10f32.ln()); } #[test] pub fn test_abs() { assert_eq!(INFINITY.abs(), INFINITY); assert_eq!(1f32.abs(), 1f32); assert_eq!(0f32.abs(), 0f32); assert_eq!((-0f32).abs(), 0f32); assert_eq!((-1f32).abs(), 1f32); assert_eq!(NEG_INFINITY.abs(), INFINITY); assert_eq!((1f32/NEG_INFINITY).abs(), 0f32); assert!(NAN.abs().is_nan()); } #[test] fn test_abs_sub() { assert_eq!((-1f32).abs_sub(1f32), 0f32); assert_eq!(1f32.abs_sub(1f32), 0f32); assert_eq!(1f32.abs_sub(0f32), 1f32); assert_eq!(1f32.abs_sub(-1f32), 2f32); assert_eq!(NEG_INFINITY.abs_sub(0f32), 0f32); assert_eq!(INFINITY.abs_sub(1f32), INFINITY); assert_eq!(0f32.abs_sub(NEG_INFINITY), INFINITY); assert_eq!(0f32.abs_sub(INFINITY), 0f32); } #[test] fn test_abs_sub_nowin() { assert!(NAN.abs_sub(-1f32).is_nan()); assert!(1f32.abs_sub(NAN).is_nan()); } #[test] fn test_signum() { assert_eq!(INFINITY.signum(), 1f32); assert_eq!(1f32.signum(), 1f32); assert_eq!(0f32.signum(), 1f32); assert_eq!((-0f32).signum(), -1f32); assert_eq!((-1f32).signum(), -1f32); assert_eq!(NEG_INFINITY.signum(), -1f32); assert_eq!((1f32/NEG_INFINITY).signum(), -1f32); assert!(NAN.signum().is_nan()); } #[test] fn test_is_positive() { assert!(INFINITY.is_positive()); assert!(1f32.is_positive()); assert!(0f32.is_positive()); assert!(!(-0f32).is_positive()); assert!(!(-1f32).is_positive()); assert!(!NEG_INFINITY.is_positive()); assert!(!(1f32/NEG_INFINITY).is_positive()); assert!(!NAN.is_positive()); } #[test] fn test_is_negative() { assert!(!INFINITY.is_negative()); assert!(!1f32.is_negative()); assert!(!0f32.is_negative()); assert!((-0f32).is_negative()); assert!((-1f32).is_negative()); assert!(NEG_INFINITY.is_negative()); assert!((1f32/NEG_INFINITY).is_negative()); assert!(!NAN.is_negative()); } #[test] fn test_is_normal() { let nan: f32 = Float::nan(); let inf: f32 = Float::infinity(); let neg_inf: f32 = Float::neg_infinity(); let zero: f32 = Float::zero(); let neg_zero: f32 = Float::neg_zero(); assert!(!nan.is_normal()); assert!(!inf.is_normal()); assert!(!neg_inf.is_normal()); assert!(!zero.is_normal()); assert!(!neg_zero.is_normal()); assert!(1f32.is_normal()); assert!(1e-37f32.is_normal()); assert!(!1e-38f32.is_normal()); } #[test] fn test_classify() { let nan: f32 = Float::nan(); let inf: f32 = Float::infinity(); let neg_inf: f32 = Float::neg_infinity(); let zero: f32 = Float::zero(); let neg_zero: f32 = Float::neg_zero(); assert_eq!(nan.classify(), Fp::Nan); assert_eq!(inf.classify(), Fp::Infinite); assert_eq!(neg_inf.classify(), Fp::Infinite); assert_eq!(zero.classify(), Fp::Zero); assert_eq!(neg_zero.classify(), Fp::Zero); assert_eq!(1f32.classify(), Fp::Normal); assert_eq!(1e-37f32.classify(), Fp::Normal); assert_eq!(1e-38f32.classify(), Fp::Subnormal); } #[test] fn test_ldexp() { // We have to use from_str until base-2 exponents // are supported in floating-point literals let f1: f32 = FromStrRadix::from_str_radix("1p-123", 16).unwrap(); let f2: f32 = FromStrRadix::from_str_radix("1p-111", 16).unwrap(); assert_eq!(Float::ldexp(1f32, -123), f1); assert_eq!(Float::ldexp(1f32, -111), f2); assert_eq!(Float::ldexp(0f32, -123), 0f32); assert_eq!(Float::ldexp(-0f32, -123), -0f32); let inf: f32 = Float::infinity(); let neg_inf: f32 = Float::neg_infinity(); let nan: f32 = Float::nan(); assert_eq!(Float::ldexp(inf, -123), inf); assert_eq!(Float::ldexp(neg_inf, -123), neg_inf); assert!(Float::ldexp(nan, -123).is_nan()); } #[test] fn test_frexp() { // We have to use from_str until base-2 exponents // are supported in floating-point literals let f1: f32 = FromStrRadix::from_str_radix("1p-123", 16).unwrap(); let f2: f32 = FromStrRadix::from_str_radix("1p-111", 16).unwrap(); let (x1, exp1) = f1.frexp(); let (x2, exp2) = f2.frexp(); assert_eq!((x1, exp1), (0.5f32, -122)); assert_eq!((x2, exp2), (0.5f32, -110)); assert_eq!(Float::ldexp(x1, exp1), f1); assert_eq!(Float::ldexp(x2, exp2), f2); assert_eq!(0f32.frexp(), (0f32, 0)); assert_eq!((-0f32).frexp(), (-0f32, 0)); } #[test] #[cfg_attr(windows, ignore)] // FIXME #8755 fn test_frexp_nowin() { let inf: f32 = Float::infinity(); let neg_inf: f32 = Float::neg_infinity(); let nan: f32 = Float::nan(); assert_eq!(match inf.frexp() { (x, _) => x }, inf); assert_eq!(match neg_inf.frexp() { (x, _) => x }, neg_inf); assert!(match nan.frexp() { (x, _) => x.is_nan() }) } #[test] fn test_integer_decode() { assert_eq!(3.14159265359f32.integer_decode(), (13176795u64, -22i16, 1i8)); assert_eq!((-8573.5918555f32).integer_decode(), (8779358u64, -10i16, -1i8)); assert_eq!(2f32.powf(100.0).integer_decode(), (8388608u64, 77i16, 1i8)); assert_eq!(0f32.integer_decode(), (0u64, -150i16, 1i8)); assert_eq!((-0f32).integer_decode(), (0u64, -150i16, -1i8)); assert_eq!(INFINITY.integer_decode(), (8388608u64, 105i16, 1i8)); assert_eq!(NEG_INFINITY.integer_decode(), (8388608u64, 105i16, -1i8)); assert_eq!(NAN.integer_decode(), (12582912u64, 105i16, 1i8)); } #[test] fn test_sqrt_domain() { assert!(NAN.sqrt().is_nan()); assert!(NEG_INFINITY.sqrt().is_nan()); assert!((-1.0f32).sqrt().is_nan()); assert_eq!((-0.0f32).sqrt(), -0.0); assert_eq!(0.0f32.sqrt(), 0.0); assert_eq!(1.0f32.sqrt(), 1.0); assert_eq!(INFINITY.sqrt(), INFINITY); } }