Function information::conditional::conditional_entropy

pub fn conditional_entropy(p_xy: &Array2<f64>) -> f64

Conditional Entropy

https://en.wikipedia.org/wiki/Conditional_entropy

Calculates the conditional entropy of a random variable X given that another random variable Y is known measured in nats.

H(X|Y) is calculated as follows:

H(X|Y) = - Σ p(x,y) * ln[ p(x,y) / p(x) ]

Usage

use ndarray::array;
use information::conditional_entropy;

let p_xy = array![[0.5, 0.0], [0.25, 0.25]];
let hx = conditional_entropy(&p_xy);
assert_eq!(hx, 0.4773856262211097);