parameters: (self, X, Y=None, eval_gradient=False)
docstring: Evaluate the kernel.
docstring_summary: Evaluate the kernel.
docstring_tokens: Evaluate the kernel .
function: def __call__(self, X, Y=None, eval_gradient=False):
          """Evaluate the kernel."""
function_tokens: def __call__ ( self , X , Y = None , eval_gradient = False ) :