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primitive_float_cbrt

malachite_float::float::arithmetic::cbrt

Function primitive_float_cbrt 

Source 
pub fn primitive_float_cbrt<T>(x: T) -> T
where
    Float: From<T> + PartialOrd<T>,
    for<'a> T: ExactFrom<&'a Float> + RoundingFrom<&'a Float> + PrimitiveFloat,
Expand description

Takes the cube root of a primitive float, returning a correctly-rounded result.

Unlike the cbrt methods of f32 and f64 (which are not guaranteed to be correctly rounded), this function returns the primitive float closest to the real cube root of the input, with ties rounded to even. It is computed by taking the cube root of the exact value of the input at the appropriate precision.

$$ f(x) = \sqrt[3]{x}. $$

§Worst-case complexity

Constant time and additional memory.

§Examples

use malachite_base::num::basic::traits::NegativeInfinity;
use malachite_float::float::arithmetic::cbrt::primitive_float_cbrt;

assert!(primitive_float_cbrt::<f64>(f64::NAN).is_nan());
assert_eq!(primitive_float_cbrt::<f64>(f64::INFINITY), f64::INFINITY);
assert_eq!(
    primitive_float_cbrt::<f64>(f64::NEGATIVE_INFINITY),
    f64::NEGATIVE_INFINITY
);
assert_eq!(primitive_float_cbrt::<f64>(27.0), 3.0);
assert_eq!(primitive_float_cbrt::<f64>(-8.0), -2.0);