diff --git a/GPy/kern/_src/stationary.py b/GPy/kern/_src/stationary.py index 1694cf48..cc5634e9 100644 --- a/GPy/kern/_src/stationary.py +++ b/GPy/kern/_src/stationary.py @@ -310,6 +310,19 @@ class Matern52(Stationary): class ExpQuad(Stationary): + """ + The Exponentiated quadratic covariance function. + + .. math:: + + k(r) = \sigma^2 (1 + \sqrt{5} r + \\frac53 r^2) \exp(- \sqrt{5} r) + + notes:: + - Yes, this is exactly the same as the RBF covariance function, but the + RBF implementation also has some features for doing variational kernels + (the psi-statistics). + + """ def __init__(self, input_dim, variance=1., lengthscale=None, ARD=False, active_dims=None, name='ExpQuad'): super(ExpQuad, self).__init__(input_dim, variance, lengthscale, ARD, active_dims, name)