//! Operations and constants for 32-bits floats (`f32` type)
-#![doc(primitive = "f32")]
-// FIXME: MIN_VALUE and MAX_VALUE literals are parsed as -inf and inf #14353
-#![allow(overflowing_literals)]
-
#![stable(feature = "rust1", since = "1.0.0")]
use intrinsics;
use mem;
use num::Float;
use num::FpCategory as Fp;
-use option::Option;
+/// The radix or base of the internal representation of `f32`.
#[stable(feature = "rust1", since = "1.0.0")]
pub const RADIX: u32 = 2;
+/// Number of significant digits in base 2.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MANTISSA_DIGITS: u32 = 24;
+/// Approximate number of significant digits in base 10.
#[stable(feature = "rust1", since = "1.0.0")]
pub const DIGITS: u32 = 6;
+/// Difference between `1.0` and the next largest representable number.
#[stable(feature = "rust1", since = "1.0.0")]
pub const EPSILON: f32 = 1.19209290e-07_f32;
-/// Smallest finite f32 value
-#[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(since = "1.0.0", reason = "use `std::f32::MIN`")]
-pub const MIN_VALUE: f32 = -3.40282347e+38_f32;
-/// Smallest positive, normalized f32 value
-#[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(since = "1.0.0", reason = "use `std::f32::MIN_POSITIVE`")]
-pub const MIN_POS_VALUE: f32 = 1.17549435e-38_f32;
-/// Largest finite f32 value
-#[stable(feature = "rust1", since = "1.0.0")]
-#[deprecated(since = "1.0.0", reason = "use `std::f32::MAX`")]
-pub const MAX_VALUE: f32 = 3.40282347e+38_f32;
-
-/// Smallest finite f32 value
+/// Smallest finite `f32` value.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MIN: f32 = -3.40282347e+38_f32;
-/// Smallest positive, normalized f32 value
+/// Smallest positive normal `f32` value.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MIN_POSITIVE: f32 = 1.17549435e-38_f32;
-/// Largest finite f32 value
+/// Largest finite `f32` value.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MAX: f32 = 3.40282347e+38_f32;
+/// One greater than the minimum possible normal power of 2 exponent.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MIN_EXP: i32 = -125;
+/// Maximum possible power of 2 exponent.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MAX_EXP: i32 = 128;
+/// Minimum possible normal power of 10 exponent.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MIN_10_EXP: i32 = -37;
+/// Maximum possible power of 10 exponent.
#[stable(feature = "rust1", since = "1.0.0")]
pub const MAX_10_EXP: i32 = 38;
+/// Not a Number (NaN).
#[stable(feature = "rust1", since = "1.0.0")]
-pub const NAN: f32 = 0.0_f32/0.0_f32;
+pub const NAN: f32 = 0.0_f32 / 0.0_f32;
+/// Infinity (∞).
#[stable(feature = "rust1", since = "1.0.0")]
-pub const INFINITY: f32 = 1.0_f32/0.0_f32;
+pub const INFINITY: f32 = 1.0_f32 / 0.0_f32;
+/// Negative infinity (-∞).
#[stable(feature = "rust1", since = "1.0.0")]
-pub const NEG_INFINITY: f32 = -1.0_f32/0.0_f32;
+pub const NEG_INFINITY: f32 = -1.0_f32 / 0.0_f32;
-/// Basic mathematial constants.
+/// Basic mathematical constants.
#[stable(feature = "rust1", since = "1.0.0")]
pub mod consts {
// FIXME: replace with mathematical constants from cmath.
- /// Archimedes' constant
+ /// Archimedes' constant (π)
#[stable(feature = "rust1", since = "1.0.0")]
pub const PI: f32 = 3.14159265358979323846264338327950288_f32;
- /// pi * 2.0
- #[unstable(feature = "core", reason = "unclear naming convention/usefulness")]
- pub const PI_2: f32 = 6.28318530717958647692528676655900576_f32;
-
- /// pi/2.0
+ /// π/2
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_PI_2: f32 = 1.57079632679489661923132169163975144_f32;
- /// pi/3.0
+ /// π/3
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_PI_3: f32 = 1.04719755119659774615421446109316763_f32;
- /// pi/4.0
+ /// π/4
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_PI_4: f32 = 0.785398163397448309615660845819875721_f32;
- /// pi/6.0
+ /// π/6
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_PI_6: f32 = 0.52359877559829887307710723054658381_f32;
- /// pi/8.0
+ /// π/8
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_PI_8: f32 = 0.39269908169872415480783042290993786_f32;
- /// 1.0/pi
+ /// 1/π
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_1_PI: f32 = 0.318309886183790671537767526745028724_f32;
- /// 2.0/pi
+ /// 2/π
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_2_PI: f32 = 0.636619772367581343075535053490057448_f32;
- /// 2.0/sqrt(pi)
+ /// 2/sqrt(π)
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_2_SQRT_PI: f32 = 1.12837916709551257389615890312154517_f32;
- #[stable(feature = "rust1", since = "1.0.0")]
- #[deprecated(since = "1.0.0", reason = "renamed to FRAC_2_SQRT_PI")]
- pub const FRAC_2_SQRTPI: f32 = 1.12837916709551257389615890312154517_f32;
-
- /// sqrt(2.0)
+ /// sqrt(2)
#[stable(feature = "rust1", since = "1.0.0")]
pub const SQRT_2: f32 = 1.41421356237309504880168872420969808_f32;
- #[stable(feature = "rust1", since = "1.0.0")]
- #[deprecated(since = "1.0.0", reason = "renamed to SQRT_2")]
- pub const SQRT2: f32 = 1.41421356237309504880168872420969808_f32;
-
- /// 1.0/sqrt(2.0)
+ /// 1/sqrt(2)
#[stable(feature = "rust1", since = "1.0.0")]
pub const FRAC_1_SQRT_2: f32 = 0.707106781186547524400844362104849039_f32;
- #[stable(feature = "rust1", since = "1.0.0")]
- #[deprecated(since = "1.0.0", reason = "renamed to FRAC_1_SQRT_2")]
- pub const FRAC_1_SQRT2: f32 = 0.707106781186547524400844362104849039_f32;
-
- /// Euler's number
+ /// Euler's number (e)
#[stable(feature = "rust1", since = "1.0.0")]
pub const E: f32 = 2.71828182845904523536028747135266250_f32;
- /// log2(e)
+ /// log<sub>2</sub>(e)
#[stable(feature = "rust1", since = "1.0.0")]
pub const LOG2_E: f32 = 1.44269504088896340735992468100189214_f32;
- /// log10(e)
+ /// log<sub>10</sub>(e)
#[stable(feature = "rust1", since = "1.0.0")]
pub const LOG10_E: f32 = 0.434294481903251827651128918916605082_f32;
- /// ln(2.0)
+ /// ln(2)
#[stable(feature = "rust1", since = "1.0.0")]
pub const LN_2: f32 = 0.693147180559945309417232121458176568_f32;
- /// ln(10.0)
+ /// ln(10)
#[stable(feature = "rust1", since = "1.0.0")]
pub const LN_10: f32 = 2.30258509299404568401799145468436421_f32;
}
-#[unstable(feature = "core", reason = "trait is unstable")]
+#[unstable(feature = "core_float",
+ reason = "stable interface is via `impl f{32,64}` in later crates",
+ issue = "32110")]
impl Float for f32 {
- #[inline]
- fn nan() -> f32 { NAN }
-
- #[inline]
- fn infinity() -> f32 { INFINITY }
-
- #[inline]
- fn neg_infinity() -> f32 { NEG_INFINITY }
-
- #[inline]
- fn zero() -> f32 { 0.0 }
-
- #[inline]
- fn neg_zero() -> f32 { -0.0 }
-
- #[inline]
- fn one() -> f32 { 1.0 }
-
/// Returns `true` if the number is NaN.
#[inline]
- fn is_nan(self) -> bool { self != self }
+ fn is_nan(self) -> bool {
+ self != self
+ }
/// Returns `true` if the number is infinite.
#[inline]
fn is_infinite(self) -> bool {
- self == Float::infinity() || self == Float::neg_infinity()
+ self == INFINITY || self == NEG_INFINITY
}
/// Returns `true` if the number is neither infinite or NaN.
let bits: u32 = unsafe { mem::transmute(self) };
match (bits & MAN_MASK, bits & EXP_MASK) {
- (0, 0) => Fp::Zero,
- (_, 0) => Fp::Subnormal,
+ (0, 0) => Fp::Zero,
+ (_, 0) => Fp::Subnormal,
(0, EXP_MASK) => Fp::Infinite,
(_, EXP_MASK) => Fp::Nan,
- _ => Fp::Normal,
+ _ => Fp::Normal,
}
}
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn mantissa_digits(_: Option<f32>) -> usize { MANTISSA_DIGITS as usize }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn digits(_: Option<f32>) -> usize { DIGITS as usize }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn epsilon() -> f32 { EPSILON }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn min_exp(_: Option<f32>) -> isize { MIN_EXP as isize }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn max_exp(_: Option<f32>) -> isize { MAX_EXP as isize }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn min_10_exp(_: Option<f32>) -> isize { MIN_10_EXP as isize }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn max_10_exp(_: Option<f32>) -> isize { MAX_10_EXP as isize }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn min_value() -> f32 { MIN }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn min_pos_value(_: Option<f32>) -> f32 { MIN_POSITIVE }
-
- #[inline]
- #[unstable(feature = "core")]
- #[deprecated(since = "1.0.0")]
- fn max_value() -> f32 { MAX }
-
- /// Returns the mantissa, exponent and sign as integers.
- fn integer_decode(self) -> (u64, i16, i8) {
- let bits: u32 = unsafe { mem::transmute(self) };
- let sign: i8 = if bits >> 31 == 0 { 1 } else { -1 };
- let mut exponent: i16 = ((bits >> 23) & 0xff) as i16;
- let mantissa = if exponent == 0 {
- (bits & 0x7fffff) << 1
- } else {
- (bits & 0x7fffff) | 0x800000
- };
- // Exponent bias + mantissa shift
- exponent -= 127 + 23;
- (mantissa as u64, exponent, sign)
- }
-
- /// Rounds towards minus infinity.
- #[inline]
- fn floor(self) -> f32 {
- unsafe { intrinsics::floorf32(self) }
- }
-
- /// Rounds towards plus infinity.
- #[inline]
- fn ceil(self) -> f32 {
- unsafe { intrinsics::ceilf32(self) }
- }
-
- /// Rounds to nearest integer. Rounds half-way cases away from zero.
- #[inline]
- fn round(self) -> f32 {
- unsafe { intrinsics::roundf32(self) }
- }
-
- /// Returns the integer part of the number (rounds towards zero).
- #[inline]
- fn trunc(self) -> f32 {
- unsafe { intrinsics::truncf32(self) }
- }
-
- /// The fractional part of the number, satisfying:
- ///
- /// ```
- /// # #![feature(core)]
- /// use std::num::Float;
- ///
- /// let x = 1.65f32;
- /// assert!(x == x.trunc() + x.fract())
- /// ```
- #[inline]
- fn fract(self) -> f32 { self - self.trunc() }
-
/// Computes the absolute value of `self`. Returns `Float::nan()` if the
/// number is `Float::nan()`.
#[inline]
#[inline]
fn signum(self) -> f32 {
if self.is_nan() {
- Float::nan()
+ NAN
} else {
unsafe { intrinsics::copysignf32(1.0, self) }
}
}
- /// Returns `true` if `self` is positive, including `+0.0` and
- /// `Float::infinity()`.
- #[inline]
- fn is_positive(self) -> bool {
- self > 0.0 || (1.0 / self) == Float::infinity()
- }
-
- /// Returns `true` if `self` is negative, including `-0.0` and
- /// `Float::neg_infinity()`.
+ /// Returns `true` if and only if `self` has a positive sign, including `+0.0`, `NaN`s with
+ /// positive sign bit and positive infinity.
#[inline]
- fn is_negative(self) -> bool {
- self < 0.0 || (1.0 / self) == Float::neg_infinity()
+ fn is_sign_positive(self) -> bool {
+ !self.is_sign_negative()
}
- /// Fused multiply-add. Computes `(self * a) + b` with only one rounding
- /// error. This produces a more accurate result with better performance than
- /// a separate multiplication operation followed by an add.
+ /// Returns `true` if and only if `self` has a negative sign, including `-0.0`, `NaN`s with
+ /// negative sign bit and negative infinity.
#[inline]
- fn mul_add(self, a: f32, b: f32) -> f32 {
- unsafe { intrinsics::fmaf32(self, a, b) }
+ fn is_sign_negative(self) -> bool {
+ // IEEE754 says: isSignMinus(x) is true if and only if x has negative sign. isSignMinus
+ // applies to zeros and NaNs as well.
+ #[repr(C)]
+ union F32Bytes {
+ f: f32,
+ b: u32
+ }
+ unsafe { F32Bytes { f: self }.b & 0x8000_0000 != 0 }
}
/// Returns the reciprocal (multiplicative inverse) of the number.
#[inline]
- fn recip(self) -> f32 { 1.0 / self }
+ fn recip(self) -> f32 {
+ 1.0 / self
+ }
#[inline]
fn powi(self, n: i32) -> f32 {
unsafe { intrinsics::powif32(self, n) }
}
- #[inline]
- fn powf(self, n: f32) -> f32 {
- unsafe { intrinsics::powf32(self, n) }
- }
-
- #[inline]
- fn sqrt(self) -> f32 {
- if self < 0.0 {
- NAN
- } else {
- unsafe { intrinsics::sqrtf32(self) }
- }
- }
-
- #[inline]
- fn rsqrt(self) -> f32 { self.sqrt().recip() }
-
- /// Returns the exponential of the number.
- #[inline]
- fn exp(self) -> f32 {
- unsafe { intrinsics::expf32(self) }
- }
-
- /// Returns 2 raised to the power of the number.
- #[inline]
- fn exp2(self) -> f32 {
- unsafe { intrinsics::exp2f32(self) }
- }
-
- /// Returns the natural logarithm of the number.
- #[inline]
- fn ln(self) -> f32 {
- unsafe { intrinsics::logf32(self) }
- }
-
- /// Returns the logarithm of the number with respect to an arbitrary base.
- #[inline]
- fn log(self, base: f32) -> f32 { self.ln() / base.ln() }
-
- /// Returns the base 2 logarithm of the number.
- #[inline]
- fn log2(self) -> f32 {
- unsafe { intrinsics::log2f32(self) }
- }
-
- /// Returns the base 10 logarithm of the number.
- #[inline]
- fn log10(self) -> f32 {
- unsafe { intrinsics::log10f32(self) }
- }
-
/// Converts to degrees, assuming the number is in radians.
#[inline]
- fn to_degrees(self) -> f32 { self * (180.0f32 / consts::PI) }
+ fn to_degrees(self) -> f32 {
+ self * (180.0f32 / consts::PI)
+ }
/// Converts to radians, assuming the number is in degrees.
#[inline]
let value: f32 = consts::PI;
self * (value / 180.0f32)
}
+
+ /// Returns the maximum of the two numbers.
+ #[inline]
+ fn max(self, other: f32) -> f32 {
+ // IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the
+ // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
+ // is either x or y, canonicalized (this means results might differ among implementations).
+ // When either x or y is a signalingNaN, then the result is according to 6.2.
+ //
+ // Since we do not support sNaN in Rust yet, we do not need to handle them.
+ // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
+ // multiplying by 1.0. Should switch to the `canonicalize` when it works.
+ (if self < other || self.is_nan() { other } else { self }) * 1.0
+ }
+
+ /// Returns the minimum of the two numbers.
+ #[inline]
+ fn min(self, other: f32) -> f32 {
+ // IEEE754 says: minNum(x, y) is the canonicalized number x if x < y, y if y < x, the
+ // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
+ // is either x or y, canonicalized (this means results might differ among implementations).
+ // When either x or y is a signalingNaN, then the result is according to 6.2.
+ //
+ // Since we do not support sNaN in Rust yet, we do not need to handle them.
+ // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
+ // multiplying by 1.0. Should switch to the `canonicalize` when it works.
+ (if self < other || other.is_nan() { self } else { other }) * 1.0
+ }
}
projects / rustc.git / blobdiff