Function stdev 

pub fn stdev<T>(data: &[T]) -> f64
where
    T: Num + NumCast + Copy,

Computes the standard deviation (σ) of a numeric data series.

NOTE: This calculates the sample standard deviation using Bessel’s correction (dividing by n - 1 instead of n) to reduce bias in estimation from a finite data sample.

Example

use quant_mathema::stats::stdev;

let data = [1.0, 2.0, 3.0, 4.0, 5.0];
let std_dev = stdev(&data);
assert!((std_dev - 1.58).abs() < 0.01);