# Primitive Type f641.0.0[−]

Expand description

A 64-bit floating point type (specifically, the “binary64” type defined in IEEE 754-2008).

This type is very similar to `f32`, but has increased precision by using twice as many bits. Please see the documentation for `f32` or Wikipedia on double precision values for more information.

See also the `std::f64::consts` module.

## Implementations

Returns the largest integer less than or equal to a number.

# Examples

```let f = 3.7_f64;
let g = 3.0_f64;
let h = -3.7_f64;

assert_eq!(f.floor(), 3.0);
assert_eq!(g.floor(), 3.0);
assert_eq!(h.floor(), -4.0);```
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Returns the smallest integer greater than or equal to a number.

# Examples

```let f = 3.01_f64;
let g = 4.0_f64;

assert_eq!(f.ceil(), 4.0);
assert_eq!(g.ceil(), 4.0);```
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Returns the nearest integer to a number. Round half-way cases away from `0.0`.

# Examples

```let f = 3.3_f64;
let g = -3.3_f64;

assert_eq!(f.round(), 3.0);
assert_eq!(g.round(), -3.0);```
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Returns the integer part of a number.

# Examples

```let f = 3.7_f64;
let g = 3.0_f64;
let h = -3.7_f64;

assert_eq!(f.trunc(), 3.0);
assert_eq!(g.trunc(), 3.0);
assert_eq!(h.trunc(), -3.0);```
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Returns the fractional part of a number.

# Examples

```let x = 3.6_f64;
let y = -3.6_f64;
let abs_difference_x = (x.fract() - 0.6).abs();
let abs_difference_y = (y.fract() - (-0.6)).abs();

assert!(abs_difference_x < 1e-10);
assert!(abs_difference_y < 1e-10);```
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Computes the absolute value of `self`. Returns `NAN` if the number is `NAN`.

# Examples

```let x = 3.5_f64;
let y = -3.5_f64;

let abs_difference_x = (x.abs() - x).abs();
let abs_difference_y = (y.abs() - (-y)).abs();

assert!(abs_difference_x < 1e-10);
assert!(abs_difference_y < 1e-10);

assert!(f64::NAN.abs().is_nan());```
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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 = 3.5_f64;

assert_eq!(f.signum(), 1.0);
assert_eq!(f64::NEG_INFINITY.signum(), -1.0);

assert!(f64::NAN.signum().is_nan());```
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Returns a number composed of the magnitude of `self` and the sign of `sign`.

Equal to `self` if the sign of `self` and `sign` are the same, otherwise equal to `-self`. If `self` is a `NAN`, then a `NAN` with the sign of `sign` is returned.

# Examples

```let f = 3.5_f64;

assert_eq!(f.copysign(0.42), 3.5_f64);
assert_eq!(f.copysign(-0.42), -3.5_f64);
assert_eq!((-f).copysign(0.42), 3.5_f64);
assert_eq!((-f).copysign(-0.42), -3.5_f64);

assert!(f64::NAN.copysign(1.0).is_nan());```
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Fused multiply-add. Computes `(self * a) + b` with only one rounding error, yielding a more accurate result than an unfused multiply-add.

Using `mul_add` may be more performant than an unfused multiply-add if the target architecture has a dedicated `fma` CPU instruction. However, this is not always true, and will be heavily dependant on designing algorithms with specific target hardware in mind.

# Examples

```let m = 10.0_f64;
let x = 4.0_f64;
let b = 60.0_f64;

// 100.0
let abs_difference = (m.mul_add(x, b) - ((m * x) + b)).abs();

assert!(abs_difference < 1e-10);```
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Calculates Euclidean division, the matching method for `rem_euclid`.

This computes the integer `n` such that `self = n * rhs + self.rem_euclid(rhs)`. In other words, the result is `self / rhs` rounded to the integer `n` such that `self >= n * rhs`.

# Examples

```let a: f64 = 7.0;
let b = 4.0;
assert_eq!(a.div_euclid(b), 1.0); // 7.0 > 4.0 * 1.0
assert_eq!((-a).div_euclid(b), -2.0); // -7.0 >= 4.0 * -2.0
assert_eq!(a.div_euclid(-b), -1.0); // 7.0 >= -4.0 * -1.0
assert_eq!((-a).div_euclid(-b), 2.0); // -7.0 >= -4.0 * 2.0```
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Calculates the least nonnegative remainder of `self (mod rhs)`.

In particular, the return value `r` satisfies `0.0 <= r < rhs.abs()` in most cases. However, due to a floating point round-off error it can result in `r == rhs.abs()`, violating the mathematical definition, if `self` is much smaller than `rhs.abs()` in magnitude and `self < 0.0`. This result is not an element of the function’s codomain, but it is the closest floating point number in the real numbers and thus fulfills the property `self == self.div_euclid(rhs) * rhs + self.rem_euclid(rhs)` approximatively.

# Examples

```let a: f64 = 7.0;
let b = 4.0;
assert_eq!(a.rem_euclid(b), 3.0);
assert_eq!((-a).rem_euclid(b), 1.0);
assert_eq!(a.rem_euclid(-b), 3.0);
assert_eq!((-a).rem_euclid(-b), 1.0);
// limitation due to round-off error
assert!((-f64::EPSILON).rem_euclid(3.0) != 0.0);```
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Raises a number to an integer power.

Using this function is generally faster than using `powf`

# Examples

```let x = 2.0_f64;
let abs_difference = (x.powi(2) - (x * x)).abs();

assert!(abs_difference < 1e-10);```
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Raises a number to a floating point power.

# Examples

```let x = 2.0_f64;
let abs_difference = (x.powf(2.0) - (x * x)).abs();

assert!(abs_difference < 1e-10);```
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Returns the square root of a number.

Returns NaN if `self` is a negative number other than `-0.0`.

# Examples

```let positive = 4.0_f64;
let negative = -4.0_f64;
let negative_zero = -0.0_f64;

let abs_difference = (positive.sqrt() - 2.0).abs();

assert!(abs_difference < 1e-10);
assert!(negative.sqrt().is_nan());
assert!(negative_zero.sqrt() == negative_zero);```
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Returns `e^(self)`, (the exponential function).

# Examples

```let one = 1.0_f64;
// e^1
let e = one.exp();

// ln(e) - 1 == 0
let abs_difference = (e.ln() - 1.0).abs();

assert!(abs_difference < 1e-10);```
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Returns `2^(self)`.

# Examples

```let f = 2.0_f64;

// 2^2 - 4 == 0
let abs_difference = (f.exp2() - 4.0).abs();

assert!(abs_difference < 1e-10);```
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Returns the natural logarithm of the number.

# Examples

```let one = 1.0_f64;
// e^1
let e = one.exp();

// ln(e) - 1 == 0
let abs_difference = (e.ln() - 1.0).abs();

assert!(abs_difference < 1e-10);```
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Returns the logarithm of the number with respect to an arbitrary base.

The result may not be correctly rounded owing to implementation details; `self.log2()` can produce more accurate results for base 2, and `self.log10()` can produce more accurate results for base 10.

# Examples

```let twenty_five = 25.0_f64;

// log5(25) - 2 == 0
let abs_difference = (twenty_five.log(5.0) - 2.0).abs();

assert!(abs_difference < 1e-10);```
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Returns the base 2 logarithm of the number.

# Examples

```let four = 4.0_f64;

// log2(4) - 2 == 0
let abs_difference = (four.log2() - 2.0).abs();

assert!(abs_difference < 1e-10);```
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Returns the base 10 logarithm of the number.

# Examples

```let hundred = 100.0_f64;

// log10(100) - 2 == 0
let abs_difference = (hundred.log10() - 2.0).abs();

assert!(abs_difference < 1e-10);```
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👎 Deprecated since 1.10.0:

you probably meant `(self - other).abs()`: this operation is `(self - other).max(0.0)` except that `abs_sub` also propagates NaNs (also known as `fdim` in C). If you truly need the positive difference, consider using that expression or the C function `fdim`, depending on how you wish to handle NaN (please consider filing an issue describing your use-case too).

The positive difference of two numbers.

• If `self <= other`: `0:0`
• Else: `self - other`

# Examples

```let x = 3.0_f64;
let y = -3.0_f64;

let abs_difference_x = (x.abs_sub(1.0) - 2.0).abs();
let abs_difference_y = (y.abs_sub(1.0) - 0.0).abs();

assert!(abs_difference_x < 1e-10);
assert!(abs_difference_y < 1e-10);```
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Returns the cube root of a number.

# Examples

```let x = 8.0_f64;

// x^(1/3) - 2 == 0
let abs_difference = (x.cbrt() - 2.0).abs();

assert!(abs_difference < 1e-10);```
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Calculates the length of the hypotenuse of a right-angle triangle given legs of length `x` and `y`.

# Examples

```let x = 2.0_f64;
let y = 3.0_f64;

// sqrt(x^2 + y^2)
let abs_difference = (x.hypot(y) - (x.powi(2) + y.powi(2)).sqrt()).abs();

assert!(abs_difference < 1e-10);```
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Computes the sine of a number (in radians).

# Examples

```let x = std::f64::consts::FRAC_PI_2;

let abs_difference = (x.sin() - 1.0).abs();

assert!(abs_difference < 1e-10);```
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Computes the cosine of a number (in radians).

# Examples

```let x = 2.0 * std::f64::consts::PI;

let abs_difference = (x.cos() - 1.0).abs();

assert!(abs_difference < 1e-10);```
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Computes the tangent of a number (in radians).

# Examples

```let x = std::f64::consts::FRAC_PI_4;
let abs_difference = (x.tan() - 1.0).abs();

assert!(abs_difference < 1e-14);```
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Computes the arcsine of a number. Return value is in radians in the range [-pi/2, pi/2] or NaN if the number is outside the range [-1, 1].

# Examples

```let f = std::f64::consts::FRAC_PI_2;

// asin(sin(pi/2))
let abs_difference = (f.sin().asin() - std::f64::consts::FRAC_PI_2).abs();

assert!(abs_difference < 1e-10);```
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Computes the arccosine of a number. Return value is in radians in the range [0, pi] or NaN if the number is outside the range [-1, 1].

# Examples

```let f = std::f64::consts::FRAC_PI_4;

// acos(cos(pi/4))
let abs_difference = (f.cos().acos() - std::f64::consts::FRAC_PI_4).abs();

assert!(abs_difference < 1e-10);```
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Computes the arctangent of a number. Return value is in radians in the range [-pi/2, pi/2];

# Examples

```let f = 1.0_f64;

// atan(tan(1))
let abs_difference = (f.tan().atan() - 1.0).abs();

assert!(abs_difference < 1e-10);```
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Computes the four quadrant arctangent of `self` (`y`) and `other` (`x`) in radians.

• `x = 0`, `y = 0`: `0`
• `x >= 0`: `arctan(y/x)` -> `[-pi/2, pi/2]`
• `y >= 0`: `arctan(y/x) + pi` -> `(pi/2, pi]`
• `y < 0`: `arctan(y/x) - pi` -> `(-pi, -pi/2)`

# Examples

```// Positive angles measured counter-clockwise
// from positive x axis
// -pi/4 radians (45 deg clockwise)
let x1 = 3.0_f64;
let y1 = -3.0_f64;

// 3pi/4 radians (135 deg counter-clockwise)
let x2 = -3.0_f64;
let y2 = 3.0_f64;

let abs_difference_1 = (y1.atan2(x1) - (-std::f64::consts::FRAC_PI_4)).abs();
let abs_difference_2 = (y2.atan2(x2) - (3.0 * std::f64::consts::FRAC_PI_4)).abs();

assert!(abs_difference_1 < 1e-10);
assert!(abs_difference_2 < 1e-10);```
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Simultaneously computes the sine and cosine of the number, `x`. Returns `(sin(x), cos(x))`.

# Examples

```let x = std::f64::consts::FRAC_PI_4;
let f = x.sin_cos();

let abs_difference_0 = (f.0 - x.sin()).abs();
let abs_difference_1 = (f.1 - x.cos()).abs();

assert!(abs_difference_0 < 1e-10);
assert!(abs_difference_1 < 1e-10);```
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Returns `e^(self) - 1` in a way that is accurate even if the number is close to zero.

# Examples

```let x = 1e-16_f64;

// for very small x, e^x is approximately 1 + x + x^2 / 2
let approx = x + x * x / 2.0;
let abs_difference = (x.exp_m1() - approx).abs();

assert!(abs_difference < 1e-20);```
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Returns `ln(1+n)` (natural logarithm) more accurately than if the operations were performed separately.

# Examples

```let x = 1e-16_f64;

// for very small x, ln(1 + x) is approximately x - x^2 / 2
let approx = x - x * x / 2.0;
let abs_difference = (x.ln_1p() - approx).abs();

assert!(abs_difference < 1e-20);```
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Hyperbolic sine function.

# Examples

```let e = std::f64::consts::E;
let x = 1.0_f64;

let f = x.sinh();
// Solving sinh() at 1 gives `(e^2-1)/(2e)`
let g = ((e * e) - 1.0) / (2.0 * e);
let abs_difference = (f - g).abs();

assert!(abs_difference < 1e-10);```
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Hyperbolic cosine function.

# Examples

```let e = std::f64::consts::E;
let x = 1.0_f64;
let f = x.cosh();
// Solving cosh() at 1 gives this result
let g = ((e * e) + 1.0) / (2.0 * e);
let abs_difference = (f - g).abs();

// Same result
assert!(abs_difference < 1.0e-10);```
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Hyperbolic tangent function.

# Examples

```let e = std::f64::consts::E;
let x = 1.0_f64;

let f = x.tanh();
// Solving tanh() at 1 gives `(1 - e^(-2))/(1 + e^(-2))`
let g = (1.0 - e.powi(-2)) / (1.0 + e.powi(-2));
let abs_difference = (f - g).abs();

assert!(abs_difference < 1.0e-10);```
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Inverse hyperbolic sine function.

# Examples

```let x = 1.0_f64;
let f = x.sinh().asinh();

let abs_difference = (f - x).abs();

assert!(abs_difference < 1.0e-10);```
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Inverse hyperbolic cosine function.

# Examples

```let x = 1.0_f64;
let f = x.cosh().acosh();

let abs_difference = (f - x).abs();

assert!(abs_difference < 1.0e-10);```
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Inverse hyperbolic tangent function.

# Examples

```let e = std::f64::consts::E;
let f = e.tanh().atanh();

let abs_difference = (f - e).abs();

assert!(abs_difference < 1.0e-10);```
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🔬 This is a nightly-only experimental API. (`float_interpolation` #86269)

Linear interpolation between `start` and `end`.

This enables linear interpolation between `start` and `end`, where start is represented by `self == 0.0` and `end` is represented by `self == 1.0`. This is the basis of all “transition”, “easing”, or “step” functions; if you change `self` from 0.0 to 1.0 at a given rate, the result will change from `start` to `end` at a similar rate.

Values below 0.0 or above 1.0 are allowed, allowing you to extrapolate values outside the range from `start` to `end`. This also is useful for transition functions which might move slightly past the end or start for a desired effect. Mathematically, the values returned are equivalent to `start + self * (end - start)`, although we make a few specific guarantees that are useful specifically to linear interpolation.

These guarantees are:

• If `start` and `end` are finite, the value at 0.0 is always `start` and the value at 1.0 is always `end`. (exactness)
• If `start` and `end` are finite, the values will always move in the direction from `start` to `end` (monotonicity)
• If `self` is finite and `start == end`, the value at any point will always be `start == end`. (consistency)

The radix or base of the internal representation of `f64`.

Number of significant digits in base 2.

Approximate number of significant digits in base 10.

Machine epsilon value for `f64`.

This is the difference between `1.0` and the next larger representable number.

Smallest finite `f64` value.

Smallest positive normal `f64` value.

Largest finite `f64` value.

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

Maximum possible power of 2 exponent.

Minimum possible normal power of 10 exponent.

Maximum possible power of 10 exponent.

Not a Number (NaN).

Infinity (∞).

Negative infinity (−∞).

Returns `true` if this value is `NaN`.

```let nan = f64::NAN;
let f = 7.0_f64;

assert!(nan.is_nan());
assert!(!f.is_nan());```
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Returns `true` if this value is positive infinity or negative infinity, and `false` otherwise.

```let f = 7.0f64;
let inf = f64::INFINITY;
let neg_inf = f64::NEG_INFINITY;
let nan = f64::NAN;

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

assert!(inf.is_infinite());
assert!(neg_inf.is_infinite());```
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Returns `true` if this number is neither infinite nor `NaN`.

```let f = 7.0f64;
let inf: f64 = f64::INFINITY;
let neg_inf: f64 = f64::NEG_INFINITY;
let nan: f64 = f64::NAN;

assert!(f.is_finite());

assert!(!nan.is_finite());
assert!(!inf.is_finite());
assert!(!neg_inf.is_finite());```
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Returns `true` if the number is subnormal.

```let min = f64::MIN_POSITIVE; // 2.2250738585072014e-308_f64
let max = f64::MAX;
let lower_than_min = 1.0e-308_f64;
let zero = 0.0_f64;

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

assert!(!zero.is_subnormal());
assert!(!f64::NAN.is_subnormal());
assert!(!f64::INFINITY.is_subnormal());
// Values between `0` and `min` are Subnormal.
assert!(lower_than_min.is_subnormal());```
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Returns `true` if the number is neither zero, infinite, subnormal, or `NaN`.

```let min = f64::MIN_POSITIVE; // 2.2250738585072014e-308f64
let max = f64::MAX;
let lower_than_min = 1.0e-308_f64;
let zero = 0.0f64;

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

assert!(!zero.is_normal());
assert!(!f64::NAN.is_normal());
assert!(!f64::INFINITY.is_normal());
// Values between `0` and `min` are Subnormal.
assert!(!lower_than_min.is_normal());```
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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.

```use std::num::FpCategory;

let num = 12.4_f64;
let inf = f64::INFINITY;

assert_eq!(num.classify(), FpCategory::Normal);
assert_eq!(inf.classify(), FpCategory::Infinite);```
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Returns `true` if `self` has a positive sign, including `+0.0`, `NaN`s with positive sign bit and positive infinity.

```let f = 7.0_f64;
let g = -7.0_f64;

assert!(f.is_sign_positive());
assert!(!g.is_sign_positive());```
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Returns `true` if `self` has a negative sign, including `-0.0`, `NaN`s with negative sign bit and negative infinity.

```let f = 7.0_f64;
let g = -7.0_f64;

assert!(!f.is_sign_negative());
assert!(g.is_sign_negative());```
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Takes the reciprocal (inverse) of a number, `1/x`.

```let x = 2.0_f64;
let abs_difference = (x.recip() - (1.0 / x)).abs();

assert!(abs_difference < 1e-10);```
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```let angle = std::f64::consts::PI;

let abs_difference = (angle.to_degrees() - 180.0).abs();

assert!(abs_difference < 1e-10);```
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```let angle = 180.0_f64;

let abs_difference = (angle.to_radians() - std::f64::consts::PI).abs();

assert!(abs_difference < 1e-10);```
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Returns the maximum of the two numbers.

```let x = 1.0_f64;
let y = 2.0_f64;

assert_eq!(x.max(y), y);```
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If one of the arguments is NaN, then the other argument is returned.

Returns the minimum of the two numbers.

```let x = 1.0_f64;
let y = 2.0_f64;

assert_eq!(x.min(y), x);```
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If one of the arguments is NaN, then the other argument is returned.

Rounds toward zero and converts to any primitive integer type, assuming that the value is finite and fits in that type.

```let value = 4.6_f64;
let rounded = unsafe { value.to_int_unchecked::<u16>() };
assert_eq!(rounded, 4);

let value = -128.9_f64;
let rounded = unsafe { value.to_int_unchecked::<i8>() };
assert_eq!(rounded, i8::MIN);```
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# Safety

The value must:

• Not be `NaN`
• Not be infinite
• Be representable in the return type `Int`, after truncating off its fractional part

Raw transmutation to `u64`.

This is currently identical to `transmute::<f64, u64>(self)` on all platforms.

See `from_bits` for some discussion of the portability of this operation (there are almost no issues).

Note that this function is distinct from `as` casting, which attempts to preserve the numeric value, and not the bitwise value.

# Examples

```assert!((1f64).to_bits() != 1f64 as u64); // to_bits() is not casting!
assert_eq!((12.5f64).to_bits(), 0x4029000000000000);
```
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Raw transmutation from `u64`.

This is currently identical to `transmute::<u64, f64>(v)` on all platforms. It turns out this is incredibly portable, for two reasons:

• Floats and Ints have the same endianness on all supported platforms.
• IEEE-754 very precisely specifies the bit layout of floats.

However there is one caveat: prior to the 2008 version of IEEE-754, how to interpret the NaN signaling bit wasn’t actually specified. Most platforms (notably x86 and ARM) picked the interpretation that was ultimately standardized in 2008, but some didn’t (notably MIPS). As a result, all signaling NaNs on MIPS are quiet NaNs on x86, and vice-versa.

Rather than trying to preserve signaling-ness cross-platform, this implementation favors preserving the exact bits. This means that any payloads encoded in NaNs will be preserved even if the result of this method is sent over the network from an x86 machine to a MIPS one.

If the results of this method are only manipulated by the same architecture that produced them, then there is no portability concern.

If the input isn’t NaN, then there is no portability concern.

If you don’t care about signaling-ness (very likely), then there is no portability concern.

Note that this function is distinct from `as` casting, which attempts to preserve the numeric value, and not the bitwise value.

# Examples

```let v = f64::from_bits(0x4029000000000000);
assert_eq!(v, 12.5);```
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Return the memory representation of this floating point number as a byte array in big-endian (network) byte order.

# Examples

```let bytes = 12.5f64.to_be_bytes();
assert_eq!(bytes, [0x40, 0x29, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]);```
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Return the memory representation of this floating point number as a byte array in little-endian byte order.

# Examples

```let bytes = 12.5f64.to_le_bytes();
assert_eq!(bytes, [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x29, 0x40]);```
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Return the memory representation of this floating point number as a byte array in native byte order.

As the target platform’s native endianness is used, portable code should use `to_be_bytes` or `to_le_bytes`, as appropriate, instead.

# Examples

```let bytes = 12.5f64.to_ne_bytes();
assert_eq!(
bytes,
if cfg!(target_endian = "big") {
[0x40, 0x29, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]
} else {
[0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x29, 0x40]
}
);```
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Create a floating point value from its representation as a byte array in big endian.

# Examples

```let value = f64::from_be_bytes([0x40, 0x29, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]);
assert_eq!(value, 12.5);```
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Create a floating point value from its representation as a byte array in little endian.

# Examples

```let value = f64::from_le_bytes([0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x29, 0x40]);
assert_eq!(value, 12.5);```
Run

Create a floating point value from its representation as a byte array in native endian.

As the target platform’s native endianness is used, portable code likely wants to use `from_be_bytes` or `from_le_bytes`, as appropriate instead.

# Examples

```let value = f64::from_ne_bytes(if cfg!(target_endian = "big") {
[0x40, 0x29, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]
} else {
[0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x29, 0x40]
});
assert_eq!(value, 12.5);```
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🔬 This is a nightly-only experimental API. (`total_cmp` #72599)

Returns an ordering between self and other values. Unlike the standard partial comparison between floating point numbers, this comparison always produces an ordering in accordance to the totalOrder predicate as defined in IEEE 754 (2008 revision) floating point standard. The values are ordered in following order:

• Negative quiet NaN
• Negative signaling NaN
• Negative infinity
• Negative numbers
• Negative subnormal numbers
• Negative zero
• Positive zero
• Positive subnormal numbers
• Positive numbers
• Positive infinity
• Positive signaling NaN
• Positive quiet NaN

Note that this function does not always agree with the `PartialOrd` and `PartialEq` implementations of `f64`. In particular, they regard negative and positive zero as equal, while `total_cmp` doesn’t.

# Example

```#![feature(total_cmp)]
struct GoodBoy {
name: String,
weight: f64,
}

let mut bois = vec![
GoodBoy { name: "Pucci".to_owned(), weight: 0.1 },
GoodBoy { name: "Woofer".to_owned(), weight: 99.0 },
GoodBoy { name: "Yapper".to_owned(), weight: 10.0 },
GoodBoy { name: "Chonk".to_owned(), weight: f64::INFINITY },
GoodBoy { name: "Abs. Unit".to_owned(), weight: f64::NAN },
GoodBoy { name: "Floaty".to_owned(), weight: -5.0 },
];

bois.sort_by(|a, b| a.weight.total_cmp(&b.weight));```
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Restrict a value to a certain interval unless it is NaN.

Returns `max` if `self` is greater than `max`, and `min` if `self` is less than `min`. Otherwise this returns `self`.

Note that this function returns NaN if the initial value was NaN as well.

# Panics

Panics if `min > max`, `min` is NaN, or `max` is NaN.

# Examples

```assert!((-3.0f64).clamp(-2.0, 1.0) == -2.0);
assert!((0.0f64).clamp(-2.0, 1.0) == 0.0);
assert!((2.0f64).clamp(-2.0, 1.0) == 1.0);
assert!((f64::NAN).clamp(-2.0, 1.0).is_nan());```
Run

## Trait Implementations

The resulting type after applying the `+` operator.

Performs the `+` operation. Read more

The resulting type after applying the `+` operator.

Performs the `+` operation. Read more

The resulting type after applying the `+` operator.

Performs the `+` operation. Read more

The resulting type after applying the `+` operator.

Performs the `+` operation. Read more

Performs the `+=` operation. Read more

Performs the `+=` operation. Read more

Returns a copy of the value. Read more

Performs copy-assignment from `source`. Read more

Formats the value using the given formatter. Read more

Returns the default value of `0.0`

Formats the value using the given formatter. Read more

The resulting type after applying the `/` operator.

Performs the `/` operation. Read more

The resulting type after applying the `/` operator.

Performs the `/` operation. Read more

The resulting type after applying the `/` operator.

Performs the `/` operation. Read more

The resulting type after applying the `/` operator.

Performs the `/` operation. Read more

Performs the `/=` operation. Read more

Performs the `/=` operation. Read more

Converts `f32` to `f64` losslessly.

Converts `i16` to `f64` losslessly.

Converts `i32` to `f64` losslessly.

Converts `i8` to `f64` losslessly.

Converts `u16` to `f64` losslessly.

Converts `u32` to `f64` losslessly.

Converts `u8` to `f64` losslessly.

Converts a string in base 10 to a float. Accepts an optional decimal exponent.

This function accepts strings such as

• ‘3.14’
• ‘-3.14’
• ‘2.5E10’, or equivalently, ‘2.5e10’
• ‘2.5E-10’
• ‘5.’
• ‘.5’, or, equivalently, ‘0.5’
• ‘inf’, ‘-inf’, ‘NaN’

Leading and trailing whitespace represent an error.

# Grammar

All strings that adhere to the following EBNF grammar will result in an `Ok` being returned:

```Float  ::= Sign? ( 'inf' | 'NaN' | Number )
Number ::= ( Digit+ |
Digit+ '.' Digit* |
Digit* '.' Digit+ ) Exp?
Exp    ::= [eE] Sign? Digit+
Sign   ::= [+-]
Digit  ::= [0-9]```

# Arguments

• src - A string

# Return value

`Err(ParseFloatError)` if the string did not represent a valid number. Otherwise, `Ok(n)` where `n` is the floating-point number represented by `src`.

The associated error which can be returned from parsing.

Formats the value using the given formatter.

The resulting type after applying the `*` operator.

Performs the `*` operation. Read more

The resulting type after applying the `*` operator.

Performs the `*` operation. Read more

The resulting type after applying the `*` operator.

Performs the `*` operation. Read more

The resulting type after applying the `*` operator.

Performs the `*` operation. Read more

Performs the `*=` operation. Read more

Performs the `*=` operation. Read more

The resulting type after applying the `-` operator.

Performs the unary `-` operation. Read more

The resulting type after applying the `-` operator.

Performs the unary `-` operation. Read more

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

This method tests for `!=`.

This method returns an ordering between `self` and `other` values if one exists. Read more

This method tests less than (for `self` and `other`) and is used by the `<` operator. Read more

This method tests less than or equal to (for `self` and `other`) and is used by the `<=` operator. Read more

This method tests greater than or equal to (for `self` and `other`) and is used by the `>=` operator. Read more

This method tests greater than (for `self` and `other`) and is used by the `>` operator. Read more

Method which takes an iterator and generates `Self` from the elements by multiplying the items. Read more

Method which takes an iterator and generates `Self` from the elements by multiplying the items. Read more

The resulting type after applying the `%` operator.

Performs the `%` operation. Read more

The resulting type after applying the `%` operator.

Performs the `%` operation. Read more

The remainder from the division of two floats.

The remainder has the same sign as the dividend and is computed as: `x - (x / y).trunc() * y`.

# Examples

```let x: f32 = 50.50;
let y: f32 = 8.125;
let remainder = x - (x / y).trunc() * y;

// The answer to both operations is 1.75
assert_eq!(x % y, remainder);```
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The resulting type after applying the `%` operator.

Performs the `%` operation. Read more

The resulting type after applying the `%` operator.

Performs the `%` operation. Read more

Performs the `%=` operation. Read more

Performs the `%=` operation. Read more

The resulting type after applying the `-` operator.

Performs the `-` operation. Read more

The resulting type after applying the `-` operator.

Performs the `-` operation. Read more

The resulting type after applying the `-` operator.

Performs the `-` operation. Read more

The resulting type after applying the `-` operator.

Performs the `-` operation. Read more

Performs the `-=` operation. Read more

Performs the `-=` operation. Read more

Method which takes an iterator and generates `Self` from the elements by “summing up” the items. Read more

Method which takes an iterator and generates `Self` from the elements by “summing up” the items. Read more

Formats the value using the given formatter.

## Blanket Implementations

Gets the `TypeId` of `self`. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Performs the conversion.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (`toowned_clone_into` #41263)

Converts the given value to a `String`. Read more