Trait ExpM1 

pub trait ExpM1 {
    // Required method
    fn exp_m1(self) -> Self;
}

Trait for computing exp(x) - 1 with high precision for small values.

This trait provides the exp_m1 function, which computes e^x - 1 more accurately than exp(x) - 1 when x is close to zero. This avoids catastrophic cancellation that occurs when subtracting two nearly equal numbers.

Mathematical Background

For small values of x, computing exp(x) - 1 directly can lose precision because exp(x) is close to 1. The exp_m1 function uses alternative algorithms (such as Taylor series) that maintain accuracy in this regime.

Examples

use num_valid::functions::ExpM1;

let x = 1e-10f64;
let result = ExpM1::exp_m1(x);
// More accurate than: x.exp() - 1.0
assert!((result - x).abs() < 1e-15);

Required Methods

fn exp_m1(self) -> Self

Returns `e^(self) - 1`` in a way that is accurate even if the number is close to zero.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl ExpM1 for f64

fn exp_m1(self) -> Self

Returns `e^(self) - 1`` in a way that is accurate even if the number is close to zero.

Implementors

impl<K: NumKernel> ExpM1 for RealValidated<K>