Function std_dev 

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

Compute sample standard deviation.

Uses Bessel’s correction (N-1 denominator) for sample standard deviation.

Example

use codec_eval::stats::std_dev;

let values = [2.0, 4.0, 4.0, 4.0, 5.0, 5.0, 7.0, 9.0];
assert!((std_dev(&values) - 2.138).abs() < 0.001);