Generate matrix-wise functions for two matrices using rbf kernel.
kernel_rbf(l, p, sigma)
(numeric) A numeric number indicating the hyperparameter (flexibility) of a specific kernel.
(integer) For polynomial, p is the power; for matern, v = p + 1 / 2; for rational, alpha = p.
(numeric) The covariance coefficient for neural network kernel.
(function) A function calculating the relevance of two matrices.
Gaussian RBF Kernels $$k_{SE}(r)=exp\Big(-\frac{r^2}{2l^2}\Big)$$
The MIT Press. Gaussian Processes for Machine Learning, 2006.