# Copyright (c) 2013, GPy authors (see AUTHORS.txt).
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
from ..core import Mapping
[docs]class Additive(Mapping):
"""
Mapping based on adding two existing mappings together.
.. math::
f(\mathbf{x}*) = f_1(\mathbf{x}*) + f_2(\mathbf(x)*)
:param mapping1: first mapping to add together.
:type mapping1: GPy.mappings.Mapping
:param mapping2: second mapping to add together.
:type mapping2: GPy.mappings.Mapping
"""
def __init__(self, mapping1, mapping2):
assert(mapping1.input_dim==mapping2.input_dim)
assert(mapping1.output_dim==mapping2.output_dim)
input_dim, output_dim = mapping1.input_dim, mapping1.output_dim
super(Additive, self).__init__(input_dim=input_dim, output_dim=output_dim)
self.mapping1 = mapping1
self.mapping2 = mapping2
self.link_parameters(self.mapping1, self.mapping2)
[docs] def f(self, X):
return self.mapping1.f(X) + self.mapping2.f(X)
[docs] def update_gradients(self, dL_dF, X):
self.mapping1.update_gradients(dL_dF, X)
self.mapping2.update_gradients(dL_dF, X)
[docs] def gradients_X(self, dL_dF, X):
return self.mapping1.gradients_X(dL_dF, X) + self.mapping2.gradients_X(dL_dF, X)