apunkt/GPy
1
0
Fork 0
mirror of https://github.com/SheffieldML/GPy.git synced 2026-05-08 11:32:39 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

shape changes for gradeitns of likelihood parameters in variational_expectations

Browse source
This commit is contained in:
James Hensman 2015-03-27 11:14:41 +00:00
parent e74bfd81c6
commit 55dba3d2d9
3 changed files with 6 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

2
GPy/inference/latent_function_inference/svgp.py
View file

@ -48,7 +48,7 @@ class SVGP(LatentFunctionInference):
#rescale the F term if working on a batch
F, dF_dmu, dF_dv = F*batch_scale, dF_dmu*batch_scale, dF_dv*batch_scale
if dF_dthetaL is not None:
dF_dthetaL = dF_dthetaL.sum(1)*batch_scale
dF_dthetaL = dF_dthetaL.sum(1).sum(1)*batch_scale
#derivatives of expected likelihood
Adv = A.T[:,:,None]*dF_dv[None,:,:] # As if dF_Dv is diagonal

9
GPy/likelihoods/gaussian.py
View file

@ -305,18 +305,17 @@ class Gaussian(Likelihood):
Ysim = np.array([np.random.normal(self.gp_link.transf(gpj), scale=np.sqrt(self.variance), size=1) for gpj in gp])
return Ysim.reshape(orig_shape)
def log_predictive_density(self, y_test, mu_star, var_star):
def log_predictive_density(self, y_test, mu_star, var_star, Y_metadata=None):
"""
assumes independence
"""
v = var_star + self.variance
return -0.5*np.log(2*np.pi) -0.5*np.log(v) - 0.5*np.square(y_test - mu_star)/v
def variational_expectations(self, Y, m, v, gh_points=None):
def variational_expectations(self, Y, m, v, gh_points=None, Y_metadata=None):
lik_var = float(self.variance)
F = -0.5*np.log(2*np.pi) -0.5*np.log(lik_var) - 0.5*(np.square(Y) + np.square(m) + v - 2*m*Y)/lik_var
dF_dmu = (Y - m)/lik_var
dF_dv = np.ones_like(v)*(-0.5/lik_var)
dF_dlik_var = np.sum(-0.5/lik_var + 0.5*(np.square(Y) + np.square(m) + v - 2*m*Y)/(lik_var**2))
dF_dtheta = [dF_dlik_var]
return F, dF_dmu, dF_dv, dF_dtheta
dF_dtheta = -0.5/lik_var + 0.5*(np.square(Y) + np.square(m) + v - 2*m*Y)/(lik_var**2)
return F, dF_dmu, dF_dv, dF_dtheta.reshape(1, Y.shape[0], Y.shape[1])

1
GPy/likelihoods/likelihood.py
View file

@ -180,6 +180,7 @@ class Likelihood(Parameterized):
if self.size:
dF_dtheta = self.dlogpdf_dtheta(X, Y[:,None]) # Ntheta x (orig size) x N_{quad_points}
dF_dtheta = np.dot(dF_dtheta, gh_w)
dF_dtheta = dF_dtheta.reshape(self.size, shape[0], shape[1])
else:
dF_dtheta = None # Not yet implemented
return F.reshape(*shape), dF_dm.reshape(*shape), dF_dv.reshape(*shape), dF_dtheta