Function reikna::integral::integrate

pub fn integrate(f: &Function, a: f64, b: f64) -> f64

Estimate the value of the integral of f over [a, b].

This is a helper function that calls integrate_wp() using a p value calculated depending on the size of [a, b]. See the documentation for integrate_wp() for more information.

The value of p is calculated by the following formula:

p = round(|b - a|) * precision

Where precision is the constant DEFAULT_PRECISION.

Note -- because of the way the precision is calculated, the computational complexity of this function grows linearly with the size of the interval. Very large intervals will have very large precision values, which can slow down computation while not providing a large improvement to accuracy. For very large intervals, is is better to use integrate_wp() directly, so the precision value can be set to a more reasonable target.

Examples

#[macro_use] extern crate reikna;
use reikna::integral::*;

let f = func!(|x| x + 4.0);
assert_eq!(integrate(&f, 0.0, 0.0), 0.0);
assert_eq!(integrate(&f, 0.0, 1.0), 4.5);