chainer.cross_entropy

chainer.cross_entropy(dist1, dist2)

Computes Cross entropy.

For two continuous distributions \(p(x), q(x)\), it is expressed as

\[H(p,q) = - \int p(x) \log q(x) dx\]

For two discrete distributions \(p(x), q(x)\), it is expressed as

\[H(p,q) = - \sum_x p(x) \log q(x)\]

This function call kl_divergence() and entropy() of dist1. Therefore, it is necessary to register KL divergence function with register_kl() decoartor and define entropy() in dist1.

Parameters

• dist1 (Distribution) – Distribution to calculate cross entropy \(p\). This is the first (left) operand of the cross entropy.

• dist2 (Distribution) – Distribution to calculate cross entropy \(q\). This is the second (right) operand of the cross entropy.

Returns

Output variable representing cross entropy \(H(p,q)\).

Return type

Variable