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Modifications to allow noise_model related parameters.

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Ricardo 2013-10-07 12:39:23 +01:00
parent d2bc9044fe
commit b20ea09f89
1 changed files with 27 additions and 54 deletions
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81
GPy/core/gp.py
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@ -58,7 +58,6 @@ class GP(GPBase):
def _get_params(self):
return np.hstack((self.kern._get_params_transformed(), self.likelihood._get_params()))
def _get_param_names(self):
return self.kern._get_param_names_transformed() + self.likelihood._get_param_names()
@ -129,7 +128,7 @@ class GP(GPBase):
debug_this # @UndefinedVariable
return mu, var
def predict(self, Xnew, which_parts='all', full_cov=False, likelihood_args=dict()):
def predict(self, Xnew, which_parts='all', full_cov=False, **likelihood_args):
"""
Predict the function(s) at the new point(s) Xnew.
@ -156,67 +155,41 @@ class GP(GPBase):
mean, var, _025pm, _975pm = self.likelihood.predictive_values(mu, var, full_cov, **likelihood_args)
return mean, var, _025pm, _975pm
def predict_single_output(self, Xnew, output=0, which_parts='all', full_cov=False):
def _raw_predict_single_output(self, _Xnew, output, which_parts='all', full_cov=False,stop=False):
"""
For a specific output, predict the function at the new point(s) Xnew.
:param Xnew: The points at which to make a prediction
:type Xnew: np.ndarray, Nnew x self.input_dim
:param output: output to predict
:type output: integer in {0,..., num_outputs-1}
:param which_parts: specifies which outputs kernel(s) to use in prediction
:type which_parts: ('all', list of bools)
:param full_cov: whether to return the full covariance matrix, or just the diagonal
:type full_cov: bool
:returns: posterior mean, a Numpy array, Nnew x self.input_dim
:returns: posterior variance, a Numpy array, Nnew x 1 if full_cov=False, Nnew x Nnew otherwise
:returns: lower and upper boundaries of the 95% confidence intervals, Numpy arrays, Nnew x self.input_dim
.. Note:: For multiple output models only
"""
assert hasattr(self,'multioutput'), 'This function is for multiple output models only.'
index = np.ones_like(Xnew)*output
Xnew = np.hstack((Xnew,index))
# normalize X values
Xnew = (Xnew.copy() - self._Xoffset) / self._Xscale
mu, var = self._raw_predict(Xnew, full_cov=full_cov, which_parts=which_parts)
# now push through likelihood
mean, var, _025pm, _975pm = self.likelihood.predictive_values(mu, var, full_cov, noise_model = output)
return mean, var, _025pm, _975pm
def _raw_predict_single_output(self, _Xnew, output=0, which_parts='all', full_cov=False,stop=False):
"""
Internal helper function for making predictions for a specific output,
does not account for normalization or likelihood
For a specific output, calls _raw_predict() at the new point(s) _Xnew.
This functions calls _add_output_index(), so _Xnew should not have an index column specifying the output.
---------
:param Xnew: The points at which to make a prediction
:type Xnew: np.ndarray, Nnew x self.input_dim
:param output: output to predict
:type output: integer in {0,..., num_outputs-1}
:type output: integer in {0,..., output_dim-1}
:param which_parts: specifies which outputs kernel(s) to use in prediction
:type which_parts: ('all', list of bools)
:param full_cov: whether to return the full covariance matrix, or just the diagonal
.. Note:: For multiple output models only
.. Note:: For multiple non-independent outputs models only.
"""
assert hasattr(self,'multioutput'), 'This function is for multiple output models only.'
# creates an index column and appends it to _Xnew
index = np.ones_like(_Xnew)*output
_Xnew = np.hstack((_Xnew,index))
_Xnew = self._add_output_index(_Xnew, output)
return self._raw_predict(_Xnew, which_parts=which_parts,full_cov=full_cov, stop=stop)
Kx = self.kern.K(_Xnew,self.X,which_parts=which_parts).T
KiKx, _ = dpotrs(self.L, np.asfortranarray(Kx), lower=1)
mu = np.dot(KiKx.T, self.likelihood.Y)
if full_cov:
Kxx = self.kern.K(_Xnew, which_parts=which_parts)
var = Kxx - np.dot(KiKx.T, Kx)
else:
Kxx = self.kern.Kdiag(_Xnew, which_parts=which_parts)
var = Kxx - np.sum(np.multiply(KiKx, Kx), 0)
var = var[:, None]
if stop:
debug_this # @UndefinedVariable
return mu, var
def predict_single_output(self, Xnew,output=0, which_parts='all', full_cov=False, likelihood_args=dict()):
"""
For a specific output, calls predict() at the new point(s) Xnew.
This functions calls _add_output_index(), so Xnew should not have an index column specifying the output.
:param Xnew: The points at which to make a prediction
:type Xnew: np.ndarray, Nnew x self.input_dim
:param which_parts: specifies which outputs kernel(s) to use in prediction
:type which_parts: ('all', list of bools)
:param full_cov: whether to return the full covariance matrix, or just the diagonal
:type full_cov: bool
:returns: mean: posterior mean, a Numpy array, Nnew x self.input_dim
:returns: var: posterior variance, a Numpy array, Nnew x 1 if full_cov=False, Nnew x Nnew otherwise
:returns: lower and upper boundaries of the 95% confidence intervals, Numpy arrays, Nnew x self.input_dim
.. Note:: For multiple non-independent outputs models only.
"""
Xnew = self._add_output_index(Xnew, output)
return self.predict(Xnew, which_parts=which_parts, full_cov=full_cov, likelihood_args=likelihood_args)