GPy/GPy/models/sparse_gp_regression.py

55 lines
1.8 KiB
Python

# Copyright (c) 2012, James Hensman
# Licensed under the BSD 3-clause license (see LICENSE.txt)
import numpy as np
from ..core import SparseGP
from .. import likelihoods
from .. import kern
class SparseGPRegression(SparseGP):
"""
Gaussian Process model for regression
This is a thin wrapper around the SparseGP class, with a set of sensible defalts
:param X: input observations
:param Y: observed values
:param kernel: a GPy kernel, defaults to rbf+white
:param normalize_X: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_X: False|True
:param normalize_Y: whether to normalize the input data before computing (predictions will be in original scales)
:type normalize_Y: False|True
:rtype: model object
.. Note:: Multiple independent outputs are allowed using columns of Y
"""
def __init__(self, X, Y, kernel=None, normalize_X=False, normalize_Y=False, Z=None, num_inducing=10, X_variance=None):
# kern defaults to rbf (plus white for stability)
if kernel is None:
kernel = kern.rbf(X.shape[1]) + kern.white(X.shape[1], 1e-3)
# Z defaults to a subset of the data
if Z is None:
i = np.random.permutation(X.shape[0])[:num_inducing]
Z = X[i].copy()
else:
assert Z.shape[1] == X.shape[1]
# likelihood defaults to Gaussian
likelihood = likelihoods.Gaussian(Y, normalize=normalize_Y)
SparseGP.__init__(self, X, likelihood, kernel, Z=Z, normalize_X=normalize_X, X_variance=X_variance)
self.ensure_default_constraints()
pass
def getstate(self):
return SparseGP.getstate(self)
def setstate(self, state):
return SparseGP.setstate(self, state)
pass