[][src]Struct half::f16

pub struct f16(_);

A 16-bit floating point type implementing the IEEE 754-2008 standard binary16 a.k.a half format.

This 16-bit floating point type is intended for efficient storage where the full range and precision of a larger floating point value is not required. Because f16 is primarily for efficient storage, floating point operations such as addition, multiplication, etc. are not implemented. Operations should be performed with f32 or higher-precision types and converted to/from f16 as necessary.

Methods

impl f16[src]

pub const fn from_bits(bits: u16) -> f16[src]

Constructs a 16-bit floating point value from the raw bits.

pub fn from_f32(value: f32) -> f16[src]

Constructs a 16-bit floating point value from a 32-bit floating point value.

If the 32-bit value is to large to fit in 16-bits, ±∞ will result. NaN values are preserved. 32-bit subnormal values are too tiny to be represented in 16-bits and result in ±0. Exponents that underflow the minimum 16-bit exponent will result in 16-bit subnormals or ±0. All other values are truncated and rounded to the nearest representable 16-bit value.

pub fn from_f64(value: f64) -> f16[src]

Constructs a 16-bit floating point value from a 64-bit floating point value.

If the 64-bit value is to large to fit in 16-bits, ±∞ will result. NaN values are preserved. 64-bit subnormal values are too tiny to be represented in 16-bits and result in ±0. Exponents that underflow the minimum 16-bit exponent will result in 16-bit subnormals or ±0. All other values are truncated and rounded to the nearest representable 16-bit value.

pub const fn to_bits(self) -> u16[src]

Converts a f16 into the underlying bit representation.

pub fn as_bits(self) -> u16[src]

Deprecated since 1.2.0:

renamed to to_bits

Converts a f16 into the underlying bit representation.

pub fn to_f32(self) -> f32[src]

Converts a f16 value into a f32 value.

This conversion is lossless as all 16-bit floating point values can be represented exactly in 32-bit floating point.

pub fn to_f64(self) -> f64[src]

Converts a f16 value into a f64 value.

This conversion is lossless as all 16-bit floating point values can be represented exactly in 64-bit floating point.

pub const fn is_nan(self) -> bool[src]

Returns true if this value is NaN and false otherwise.

Examples

let nan = f16::NAN;
let f = f16::from_f32(7.0_f32);

assert!(nan.is_nan());
assert!(!f.is_nan());

pub const fn is_infinite(self) -> bool[src]

Returns true if this value is ±∞ and false otherwise.

Examples

let f = f16::from_f32(7.0f32);
let inf = f16::INFINITY;
let neg_inf = f16::NEG_INFINITY;
let nan = f16::NAN;

assert!(!f.is_infinite());
assert!(!nan.is_infinite());

assert!(inf.is_infinite());
assert!(neg_inf.is_infinite());

pub const fn is_finite(self) -> bool[src]

Returns true if this number is neither infinite nor NaN.

Examples

let f = f16::from_f32(7.0f32);
let inf = f16::INFINITY;
let neg_inf = f16::NEG_INFINITY;
let nan = f16::NAN;

assert!(f.is_finite());

assert!(!nan.is_finite());
assert!(!inf.is_finite());
assert!(!neg_inf.is_finite());

pub fn is_normal(self) -> bool[src]

Returns true if the number is neither zero, infinite, subnormal, or NaN.

Examples

let min = f16::MIN_POSITIVE;
let max = f16::MAX;
let lower_than_min = f16::from_f32(1.0e-10_f32);
let zero = f16::from_f32(0.0_f32);

assert!(min.is_normal());
assert!(max.is_normal());

assert!(!zero.is_normal());
assert!(!f16::NAN.is_normal());
assert!(!f16::INFINITY.is_normal());
// Values between `0` and `min` are Subnormal.
assert!(!lower_than_min.is_normal());

pub fn classify(self) -> FpCategory[src]

Returns the floating point category of the number.

If only one property is going to be tested, it is generally faster to use the specific predicate instead.

Examples

use std::num::FpCategory;

let num = f16::from_f32(12.4_f32);
let inf = f16::INFINITY;

assert_eq!(num.classify(), FpCategory::Normal);
assert_eq!(inf.classify(), FpCategory::Infinite);

pub fn signum(self) -> f16[src]

Returns a number that represents the sign of self.

  • 1.0 if the number is positive, +0.0 or INFINITY
  • -1.0 if the number is negative, -0.0 or NEG_INFINITY
  • NAN if the number is NAN

Examples

let f = f16::from_f32(3.5_f32);

assert_eq!(f.signum(), f16::from_f32(1.0));
assert_eq!(f16::NEG_INFINITY.signum(), f16::from_f32(-1.0));

assert!(f16::NAN.signum().is_nan());

pub const fn is_sign_positive(self) -> bool[src]

Returns true if and only if self has a positive sign, including +0.0, NaNs with a positive sign bit and +∞.

Examples

let nan = f16::NAN;
let f = f16::from_f32(7.0_f32);
let g = f16::from_f32(-7.0_f32);

assert!(f.is_sign_positive());
assert!(!g.is_sign_positive());
// `NaN` can be either positive or negative
assert!(nan.is_sign_positive() != nan.is_sign_negative());

pub const fn is_sign_negative(self) -> bool[src]

Returns true if and only if self has a negative sign, including -0.0, NaNs with a negative sign bit and −∞.

Examples

let nan = f16::NAN;
let f = f16::from_f32(7.0f32);
let g = f16::from_f32(-7.0f32);

assert!(!f.is_sign_negative());
assert!(g.is_sign_negative());
// `NaN` can be either positive or negative
assert!(nan.is_sign_positive() != nan.is_sign_negative());

pub const DIGITS: u32[src]

Approximate number of f16 significant digits in base 10.

pub const EPSILON: f16[src]

f16 machine epsilon value.

This is the difference between 1.0 and the next largest representable number.

pub const INFINITY: f16[src]

f16 positive Infinity (+∞).

pub const MANTISSA_DIGITS: u32[src]

Number of f16 significant digits in base 2.

pub const MAX: f16[src]

Largest finite f16 value.

pub const MAX_10_EXP: i32[src]

Maximum possible f16 power of 10 exponent.

pub const MAX_EXP: i32[src]

Maximum possible f16 power of 2 exponent.

pub const MIN: f16[src]

Smallest finite f16 value.

pub const MIN_10_EXP: i32[src]

Minimum possible normal f16 power of 10 exponent.

pub const MIN_EXP: i32[src]

One greater than the minimum possible normal f16 power of 2 exponent.

pub const MIN_POSITIVE: f16[src]

Smallest positive normal f16 value.

pub const NAN: f16[src]

f16 Not a Number (NaN).

pub const NEG_INFINITY: f16[src]

f16 negative infinity (-∞).

pub const RADIX: u32[src]

The radix or base of the internal representation of f16.

pub const MIN_POSITIVE_SUBNORMAL: f16[src]

Minimum positive subnormal f16 value.

pub const MAX_SUBNORMAL: f16[src]

Maximum subnormal f16 value.

pub const ONE: f16[src]

f16 1

pub const ZERO: f16[src]

f16 0

pub const NEG_ZERO: f16[src]

f16 -0

pub const E: f16[src]

f16 Euler's number (ℯ).

pub const PI: f16[src]

f16 Archimedes' constant (π).

pub const FRAC_1_PI: f16[src]

f16 1/π

pub const FRAC_1_SQRT_2: f16[src]

f16 1/√2

pub const FRAC_2_PI: f16[src]

f16 2/π

pub const FRAC_2_SQRT_PI: f16[src]

f16 2/√π

pub const FRAC_PI_2: f16[src]

f16 π/2

pub const FRAC_PI_3: f16[src]

f16 π/3

pub const FRAC_PI_4: f16[src]

f16 π/4

pub const FRAC_PI_6: f16[src]

f16 π/6

pub const FRAC_PI_8: f16[src]

f16 π/8

pub const LN_10: f16[src]

f16 𝗅𝗇 10

pub const LN_2: f16[src]

f16 𝗅𝗇 2

pub const LOG10_E: f16[src]

f16 𝗅𝗈𝗀₁₀ℯ

pub const LOG2_E: f16[src]

f16 𝗅𝗈𝗀₂ℯ

pub const SQRT_2: f16[src]

f16 √2

Trait Implementations

impl From<f16> for f32[src]

impl From<f16> for f64[src]

impl From<i8> for f16[src]

impl From<u8> for f16[src]

impl Clone for f16[src]

impl Copy for f16[src]

impl Default for f16[src]

impl PartialEq<f16> for f16[src]

impl PartialOrd<f16> for f16[src]

impl LowerExp for f16[src]

impl UpperExp for f16[src]

impl Display for f16[src]

impl Debug for f16[src]

impl FromStr for f16[src]

type Err = ParseFloatError

The associated error which can be returned from parsing.

impl Serialize for f16[src]

impl<'de> Deserialize<'de> for f16[src]

Auto Trait Implementations

impl Send for f16

impl Sync for f16

impl Unpin for f16

impl UnwindSafe for f16

impl RefUnwindSafe for f16

Blanket Implementations

impl<T, U> Into<U> for T where
    U: From<T>, 
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impl<T> From<T> for T[src]

impl<T> ToOwned for T where
    T: Clone
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type Owned = T

The resulting type after obtaining ownership.

impl<T> ToString for T where
    T: Display + ?Sized
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impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
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type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<T> Borrow<T> for T where
    T: ?Sized
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impl<T> BorrowMut<T> for T where
    T: ?Sized
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impl<T> Any for T where
    T: 'static + ?Sized
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impl<T> DeserializeOwned for T where
    T: Deserialize<'de>, 
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