asserting::assertions

Trait AssertIsCloseToWithDefaultMargin

Source 
pub trait AssertIsCloseToWithDefaultMargin<E> {
    // Required methods
    fn is_close_to(self, expected: E) -> Self;
    fn is_not_close_to(self, expected: E) -> Self;
}
Available on crate feature float-cmp only.
Expand description

Assert approximate equality for floating point numbers.

§Examples

use asserting::prelude::*;

assert_that!(5.0_f32 / 2.0).is_close_to(2.5);
assert_that!(10.0_f64 / 8.0).is_close_to(1.25);

assert_that!(5.0_f32 / 2.5).is_not_close_to(2.01);
assert_that!(10.0_f64 / 8.0).is_not_close_to(1.255);

Required Methods§

Source

fn is_close_to(self, expected: E) -> Self

Verifies that the actual value is approximately equal to the expected value.

For the approximation, a default margin with 4 * epsilon and 4 * ULPS is used.

§Examples
use asserting::prelude::*;

assert_that!(5.0_f32 / 2.0).is_close_to(2.5);
assert_that!(10.0_f64 / 8.0).is_close_to(1.25);

The following articles describe the challenges with comparing floating point numbers and the meaning of the epsilon and ULPS values:

Source

fn is_not_close_to(self, expected: E) -> Self

Verifies that the actual value is not approximately equal to the expected value.

For the approximation, a default margin with 4 * epsilon and 4 * ULPS is used.

§Examples
use asserting::prelude::*;

assert_that!(10.0_f32 / 2.0).is_not_close_to(5.01);
assert_that!(10.0_f64 / 2.0).is_not_close_to(5.01);

The following articles describe the challenges with comparing floating point numbers and the meaning of the epsilon and ULPS values:

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.

Implementors§