NAME

Algorithm::KernelKMeans::Util

DESCRIPTION

This module provides some utility functions suitable to use with Algorithm::KernelKMeans.

FUNCTIONS

This module exports nothing by default. You can import functions below:

centroid($cluster)

Takes array ref of vertices and returns centroid vector of the cluster.

inner_product($v, $u)

Calculates inner product of $v and $u.

generate_polynominal_kernel($l, $p)

Generates a polynominal kernel function and returns it.

Generated kernel function will be formed K(x1, x2) = ($l + x1 . x2)^$p, where "x1 . x2" represents inner product.

generate_gaussian_kernel($sigma)

K(x1, x2) = exp(-||x1 - x2||^2 / (2 * $sigma)^2)

generate_sigmoid_kernel($s, $theta)

K(x1, x2) = tanh($s * (x1 . x2) + $theta)

AUTHOR

Koichi SATOH <r.sekia@gmail.com>