Returns similarity between two vectors.
Returns similarity between two vectors.
[Dx1] vector
[Dx1] vector
[N x D] vector, N - number of random variables, D - dimensionality of random variable
[N x N] covariance matrix
[N x D] vector, N - number of random variables, D - dimensionality of random variable
[M x D] vector, N - number of random variables, D - dimensionality of random variable
[N x M] covariance matrix
[N x D] vector, N - number of random variables, D - dimensionality of random variable
([N x N] covariance matrix, [N x N] partial derivatives matrix with respect to sf parameter, array of [NxN] partial derivative matrix with respect to ell parameters)
- vector of log of length scale standard deviation
- log of signal standard deviation
Implementation based 'http://www.gaussianprocess.org/gpml/code/matlab/doc/index.html'
Squared Exponential covariance function with isotropic distance measure. The covariance function is parameterized as:
k(xp,xq) = sf2 * exp(-(xp - xq)'*inv(P)*(xp - x^q)/2)
where the P matrix is ell2 times the unit matrix and sf2 is the signal variance.
Copyright (c) by Carl Edward Rasmussen and Hannes Nickisch, 2010-09-10.
- log of signal standard deviation
- vector of log of length scale standard deviation