Macro assert_y 

macro_rules! assert_y {
    ($function:expr, $x:expr, $expected:expr $(, $msg:literal $(, $($args:tt),*)?)?) => { ... };
}

Asserts that evaluating a polynomial at a given x matches the expected y value within floating-point epsilon tolerance.

Useful for spot-checking specific predictions of the model.

Arguments

• $function - The polynomial under test (must implement AsRef<Polynomial<...>>).
• $x - The input x value where the polynomial is evaluated.
• $expected - The expected result of the polynomial evaluation.

Panics

Panics if the evaluated value differs from the expected value by more than machine epsilon for the type T.

Example

use polyfit::{function, assert_y};

function!(test(x) = 8.0 + 7.0 x^1 + 6.0 x^2);

// 8 + 7*2 + 6*4 = 8 + 14 + 24 = 46
assert_y!(test, 2.0, 46.0);