pub fn gauss_legendre_quadrature<F, Y>(f: F, n: usize, (a, b): (f64, f64)) -> Y
where
    F: Fn(f64) -> Y,
    Y: GLKIntegrable,
{
    unit_gauss_legendre_quadrature(|x| f(x * (b - a) / 2f64 + (a + b) / 2f64), n) * ((b - a) / 2f64)
}
Gauss Legendre Quadrature

# Type
* `f, n, (a,b) -> Y`
* `Y` implements [`GLKIntegrable`], like `f64` or `C64` (`complex` feature
only)
* `f`: Numerical function (`Fn(f64) -> Y`)
* `n`: Order of Legendre polynomial (up to 16)
* `(a,b)`: Interval of integration

# Reference
* A. N. Lowan et al. (1942)
src/numerical/integral.rs