Function iqr 

pub fn iqr(values: &[f64]) -> f64

Compute interquartile range (IQR = Q3 - Q1).

The IQR is a robust measure of spread that is not affected by outliers.

Example

use codec_eval::stats::iqr;

let values = [1.0, 2.0, 3.0, 4.0, 5.0];
assert!((iqr(&values) - 2.0).abs() < 0.001);  // Q3(4) - Q1(2) = 2