[GPU] vardtc_likelihood

This commit is contained in:
Zhenwen Dai 2014-04-03 10:59:17 +01:00
parent f1d831c5f1
commit daf5a877f3
2 changed files with 142 additions and 224 deletions

View file

@ -15,7 +15,7 @@ try:
from scikits.cuda import cublas
import pycuda.autoinit
from pycuda.reduction import ReductionKernel
from ...util.linalg_gpu import logDiagSum, strideSum
from ...util.linalg_gpu import logDiagSum, strideSum, mul_bcast, sum_axis
except:
pass
@ -49,7 +49,7 @@ class VarDTC_GPU(object):
# Initialize GPU caches
self.gpuCache = None
def _initGPUCache(self, num_inducing, output_dim):
def _initGPUCache(self, num_inducing, output_dim, Y):
if self.gpuCache == None:
self.gpuCache = {# inference_likelihood
'Kmm_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
@ -63,17 +63,19 @@ class VarDTC_GPU(object):
'KmmInvPsi2P_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
'dL_dpsi2R_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
'dL_dKmm_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
'psi1Y_gpu' :gpuarray.empty((num_inducing,output_dim),np.float64,order='F'),
'psi2_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
'beta_gpu' :gpuarray.empty((output_dim,),np.float64,order='F'),
'Y_gpu' :gpuarray.to_gpu(np.asfortranarray(Y)),
'betaY_gpu' :gpuarray.empty(Y.shape,np.float64,order='F'),
'psi2_t_gpu' :gpuarray.empty((self.batchsize,num_inducing,num_inducing),np.float64,order='F'),
# inference_minibatch
}
self.gpuCache['ones_gpu'].fill(1.0)
def set_limit(self, limit):
self.get_trYYT.limit = limit
self.get_YYTfactor.limit = limit
Y_gpu = self.gpuCache['Y_gpu']
self._trYYT = cublas.cublasDdot(self.cublas_handle, Y_gpu.size, Y_gpu.gpudata, 1, Y_gpu.gpudata, 1)
def _get_trYYT(self, Y):
return param_to_array(np.sum(np.square(Y)))
def _get_YYTfactor(self, Y):
"""
find a matrix L which satisfies LLT = YYT.
@ -94,7 +96,7 @@ class VarDTC_GPU(object):
Cached intermediate results: Kmm, KmmInv,
"""
num_inducing = Z.shape[0]
num_inducing = Z.shape[0]
num_data, output_dim = Y.shape
self._initGPUCache(num_inducing, output_dim)
@ -107,59 +109,120 @@ class VarDTC_GPU(object):
#see whether we've got a different noise variance for each datum
beta = 1./np.fmax(likelihood.variance, 1e-6)
het_noise = beta.size > 1
trYYT = self.get_trYYT(Y)
trYYT = self._trYYT
psi1Y_gpu = self.gpuCache['psi1Y_gpu']
psi2_gpu = self.gpuCache['psi2_gpu']
beta_gpu = self.gpuCache['beta_gpu']
Y_gpu = self.gpuCache['Y_gpu']
betaY_gpu = self.gpuCache['betaY_gpu']
psi2_t_gpu = self.gpuCache['psi2_t_gpu']
psi2_full = np.zeros((num_inducing,num_inducing))
psi1Y_full = np.zeros((num_inducing,output_dim)) # DxM
psi0_full = 0
YRY_full = 0
for n_start in xrange(0,num_data,self.batchsize):
n_end = min(self.batchsize+n_start, num_data)
Y_slice = Y[n_start:n_end]
X_slice = X[n_start:n_end]
if uncertain_inputs:
psi0 = kern.psi0(Z, X_slice)
psi1 = kern.psi1(Z, X_slice)
psi2 = kern.psi2(Z, X_slice)
else:
psi0 = kern.Kdiag(X_slice)
psi1 = kern.K(X_slice, Z)
psi2 = None
if het_noise:
beta_slice = beta[n_start:n_end]
psi0_full += (beta_slice*psi0).sum()
psi1Y_full += np.dot(psi1.T,beta_slice[:,None]*Y_slice) # MxD
YRY_full += (beta_slice*np.square(Y_slice).sum(axis=-1)).sum()
else:
psi0_full += psi0.sum()
psi1Y_full += np.dot(psi1.T,Y_slice) # MxD
if uncertain_inputs:
if het_noise:
psi2_full += np.einsum('n,nmo->mo',beta_slice,psi2)
else:
psi2_full += psi2.sum(axis=0)
else:
if het_noise:
psi2_full += np.einsum('n,nm,no->mo',beta_slice,psi1,psi1)
else:
psi2_full += tdot(psi1.T)
if not het_noise:
psi0_full *= beta
psi1Y_full *= beta
psi2_full *= beta
if het_noise:
beta_gpu.set(np.asfortranarray(beta))
mul_bcast(betaY_gpu,beta_gpu,Y_gpu,beta_gpu.size)
YRY_full = cublas.cublasDdot(self.cublas_handle, Y_gpu.size, betaY_gpu.gpudata, 1, Y_gpu.gpudata, 1)
else:
beta_gpu.fill(beta)
betaY_gpu.fill(0.)
cublas.cublasDaxpy(self.cublas_handle, betaY_gpu.size, beta, Y_gpu.gpudata, 1, betaY_gpu, 1)
YRY_full = trYYT*beta
psi1Y_gpu = gpuarray.to_gpu(np.asfortranarray(psi1Y_full))
psi2_gpu = gpuarray.to_gpu(np.asfortranarray(psi2_full))
if kern.useGPU:
psi1Y_gpu.fill(0.)
psi2_gpu.fill(0.)
psi0_full = 0
for n_start in xrange(0,num_data,self.batchsize):
n_end = min(self.batchsize+n_start, num_data)
ndata = n_end - n_start
Y_slice = Y[n_start:n_end]
X_slice = X[n_start:n_end]
beta_gpu_slice = beta_gpu[n_start:n_end]
betaY_gpu_slice = betaY_gpu[n_start:n_end]
if ndata==self.batchsize:
psi2_t_gpu_slice = psi2_t_gpu
else:
psi2_t_gpu_slice = psi2_t_gpu[0:ndata]
if uncertain_inputs:
psi0p_gpu = kern.psi0(Z, X_slice)
psi1p_gpu = kern.psi1(Z, X_slice)
psi2p_gpu = kern.psi2(Z, X_slice)
else:
psi0p_gpu = kern.Kdiag(X_slice)
psi1p_gpu = kern.K(X_slice, Z)
cublas.cublasDgemm(self.cublas_handle, 'T', 'N', num_inducing, output_dim, ndata, 1.0, psi1p_gpu.gpudata, ndata, betaY_gpu_slice.gpudata, ndata, 1.0, psi1Y_gpu.gpudata, num_inducing)
if het_noise:
psi0_full += cublas.cublasDdot(self.cublas_handle, psi0p_gpu.size, beta_gpu_slice.gpudata, 1, psi0p_gpu.gpudata, 1)
else:
psi0_full += gpuarray.sum(psi0p_gpu).get()
if uncertain_inputs:
if het_noise:
mul_bcast(psi2_t_gpu_slice,beta_gpu_slice,psi2p_gpu,beta_gpu_slice.size)
sum_axis(psi2_gpu,psi2_t_gpu_slice,1,ndata)
else:
sum_axis(psi2_gpu,psi2p_gpu,1,ndata)
else:
if het_noise:
psi1_t_gpu = psi2_t_gpu_slice[:,:,0]
mul_bcast(psi1_t_gpu,beta_gpu_slice,psi1p_gpu,beta_gpu_slice.size)
cublas.cublasDgemm(self.cublas_handle, 'T', 'N', num_inducing, num_inducing, ndata, 1.0, psi1p_gpu.gpudata, ndata, psi1_t_gpu.gpudata, ndata, 1.0, psi2_gpu.gpudata, num_inducing)
else:
cublas.cublasDgemm(self.cublas_handle, 'T', 'N', num_inducing, num_inducing, ndata, beta, psi1p_gpu.gpudata, ndata, psi1p_gpu.gpudata, ndata, 1.0, psi2_gpu.gpudata, num_inducing)
if not het_noise:
psi0_full *= beta
if uncertain_inputs:
cublas.cublasDscal(self.cublas_handle, psi2_gpu.size, beta, psi2_gpu.gpudata, 1)
else:
psi2_full = np.zeros((num_inducing,num_inducing),order='F')
psi1Y_full = np.zeros((num_inducing,output_dim),order='F') # MxD
psi0_full = 0
YRY_full = 0
for n_start in xrange(0,num_data,self.batchsize):
n_end = min(self.batchsize+n_start, num_data)
Y_slice = Y[n_start:n_end]
X_slice = X[n_start:n_end]
if uncertain_inputs:
psi0 = kern.psi0(Z, X_slice)
psi1 = kern.psi1(Z, X_slice)
psi2 = kern.psi2(Z, X_slice)
else:
psi0 = kern.Kdiag(X_slice)
psi1 = kern.K(X_slice, Z)
if het_noise:
beta_slice = beta[n_start:n_end]
psi0_full += (beta_slice*psi0).sum()
psi1Y_full += np.dot(psi1.T,beta_slice[:,None]*Y_slice) # MxD
YRY_full += (beta_slice*np.square(Y_slice).sum(axis=-1)).sum()
else:
psi0_full += psi0.sum()
psi1Y_full += np.dot(psi1.T,Y_slice) # MxD
if uncertain_inputs:
if het_noise:
psi2_full += np.einsum('n,nmo->mo',beta_slice,psi2)
else:
psi2_full += psi2.sum(axis=0)
else:
if het_noise:
psi2_full += np.einsum('n,nm,no->mo',beta_slice,psi1,psi1)
else:
psi2_full += tdot(psi1.T)
if not het_noise:
psi0_full *= beta
psi1Y_full *= beta
psi2_full *= beta
YRY_full = trYYT*beta
psi1Y_gpu.set(psi1Y_full)
psi2_gpu.set(psi2_full)
#======================================================================
# Compute Common Components