rbf kernel gpu implementation ready

This commit is contained in:
Zhenwen Dai 2014-06-20 15:02:00 +01:00
parent e0412ebf54
commit 155511b761
2 changed files with 48 additions and 254 deletions

View file

@ -3,9 +3,10 @@ The module for psi-statistics for RBF kernel
"""
import numpy as np
from GPy.util.caching import Cacher
from ....util.caching import Cache_this
from . import PSICOMP_RBF
from ....util import gpu_init
from ....util.linalg_gpu import sum_axis
try:
import pycuda.gpuarray as gpuarray
@ -251,19 +252,25 @@ class PSICOMP_RBF_GPU(PSICOMP_RBF):
'psi1_gpu' :gpuarray.empty((N,M),np.float64,order='F'),
'psi2_gpu' :gpuarray.empty((M,M),np.float64,order='F'),
'psi2n_gpu' :gpuarray.empty((N,M,M),np.float64,order='F'),
'dL_dpsi1_gpu' :gpuarray.empty((N,M),np.float64,order='F'),
'dL_dpsi2_gpu' :gpuarray.empty((M,M),np.float64,order='F'),
# derivatives
'dvar_gpu' :gpuarray.empty((self.blocknum,),np.float64, order='F'),
'dl_gpu' :gpuarray.empty((Q,self.blocknum),np.float64, order='F'),
'dZ_gpu' :gpuarray.empty((M,Q),np.float64, order='F'),
'dmu_gpu' :gpuarray.empty((N,Q,self.blocknum),np.float64, order='F'),
'dS_gpu' :gpuarray.empty((N,Q,self.blocknum),np.float64, order='F'),
# gradients
'grad_l_gpu' :gpuarray.empty((Q,),np.float64,order='F'),
'grad_Z_gpu' :gpuarray.empty((M,Q),np.float64,order='F'),
# grad
'grad_l_gpu' :gpuarray.empty((Q,),np.float64, order='F'),
'grad_mu_gpu' :gpuarray.empty((N,Q,),np.float64, order='F'),
'grad_S_gpu' :gpuarray.empty((N,Q,),np.float64, order='F'),
}
def sync_params(self, lengthscale, Z, mu, S):
self.gpuCache['l_gpu'].set(np.asfortranarray(lengthscale))
if len(lengthscale)==1:
self.gpuCache['l_gpu'].fill(lengthscale)
else:
self.gpuCache['l_gpu'].set(np.asfortranarray(lengthscale))
self.gpuCache['Z_gpu'].set(np.asfortranarray(Z))
self.gpuCache['mu_gpu'].set(np.asfortranarray(mu))
self.gpuCache['S_gpu'].set(np.asfortranarray(S))
@ -274,23 +281,21 @@ class PSICOMP_RBF_GPU(PSICOMP_RBF):
self.gpuCache['dZ_gpu'].fill(0.)
self.gpuCache['dmu_gpu'].fill(0.)
self.gpuCache['dS_gpu'].fill(0.)
self.gpuCache['grad_l_gpu'].fill(0.)
self.gpuCache['grad_mu_gpu'].fill(0.)
self.gpuCache['grad_S_gpu'].fill(0.)
def get_dimensions(self, Z, variational_posterior):
return variational_posterior.mean.shape[0], Z.shape[0], Z.shape[1]
# @Cache_this(limit=1, ignore_args=(0,))
@Cache_this(limit=1, ignore_args=(0,))
def psicomputations(self, variance, lengthscale, Z, variational_posterior):
"""
Z - MxQ
mu - NxQ
S - NxQ
gamma - NxQ
"""
# here are the "statistics" for psi0, psi1 and psi2
# Produced intermediate results:
# _psi1 NxM
mu = variational_posterior.mean
S = variational_posterior.variance
N = mu.shape[0]
M = Z.shape[0]
Q = Z.shape[1]
N,M,Q = self.get_dimensions(Z, variational_posterior)
self._initGPUCache(N,M,Q)
self.sync_params(lengthscale, Z, variational_posterior.mean, variational_posterior.variance)
@ -312,33 +317,11 @@ class PSICOMP_RBF_GPU(PSICOMP_RBF):
else:
return psi0_gpu.get(), psi1_gpu.get(), psi2_gpu.get()
psi0 = np.empty(mu.shape[0])
psi0[:] = variance
psi1 = _psi1computations(variance, lengthscale, Z, mu, S)
self.g_psi1computations(psi1_gpu, np.float64(variance),l_gpu,Z_gpu,mu_gpu,S_gpu, np.int32(N), np.int32(M), np.int32(Q), block=(self.threadnum,1,1), grid=(self.blocknum,1))
psi1g = psi1_gpu.get()
print np.abs(psi1-psi1g).max()
psi2 = _psi2computations(variance, lengthscale, Z, mu, S).sum(axis=0)
self.g_psi2computations(psi2_gpu, psi2n_gpu, np.float64(variance),l_gpu,Z_gpu,mu_gpu,S_gpu, np.int32(N), np.int32(M), np.int32(Q), block=(self.threadnum,1,1), grid=(self.blocknum,1))
psi2g = psi2_gpu.get()
print np.abs(psi2-psi2g).max()
return psi0, psi1, psi2
# @Cache_this(limit=1, ignore_args=(0,1,2,3))
@Cache_this(limit=1, ignore_args=(0,1,2,3))
def psiDerivativecomputations(self, dL_dpsi0, dL_dpsi1, dL_dpsi2, variance, lengthscale, Z, variational_posterior):
ARD = (len(lengthscale)!=1)
dvar_psi1, dl_psi1, dZ_psi1, dmu_psi1, dS_psi1 = _psi1compDer(dL_dpsi1, variance, lengthscale, Z, variational_posterior.mean, variational_posterior.variance)
dvar_psi2, dl_psi2, dZ_psi2, dmu_psi2, dS_psi2 = _psi2compDer(dL_dpsi2, variance, lengthscale, Z, variational_posterior.mean, variational_posterior.variance)
mu = variational_posterior.mean
S = variational_posterior.variance
N = mu.shape[0]
M = Z.shape[0]
Q = Z.shape[1]
N,M,Q = self.get_dimensions(Z, variational_posterior)
psi1_gpu = self.gpuCache['psi1_gpu']
psi2n_gpu = self.gpuCache['psi2n_gpu']
l_gpu = self.gpuCache['l_gpu']
@ -350,207 +333,35 @@ class PSICOMP_RBF_GPU(PSICOMP_RBF):
dZ_gpu = self.gpuCache['dZ_gpu']
dmu_gpu = self.gpuCache['dmu_gpu']
dS_gpu = self.gpuCache['dS_gpu']
grad_l_gpu = self.gpuCache['grad_l_gpu']
grad_mu_gpu = self.gpuCache['grad_mu_gpu']
grad_S_gpu = self.gpuCache['grad_S_gpu']
if self.GPU_direct:
dL_dpsi1_gpu = dL_dpsi1
dL_dpsi2_gpu = dL_dpsi2
else:
dL_dpsi1_gpu = gpuarray.to_gpu(np.asfortranarray(dL_dpsi1))
dL_dpsi2_gpu = gpuarray.to_gpu(np.asfortranarray(dL_dpsi2))
dL_dpsi1_gpu = self.gpuCache['dL_dpsi1_gpu']
dL_dpsi2_gpu = self.gpuCache['dL_dpsi2_gpu']
dL_dpsi1_gpu.set(np.asfortranarray(dL_dpsi1))
dL_dpsi2_gpu.set(np.asfortranarray(dL_dpsi2))
self.reset_derivative()
self.g_psi1compDer(dvar_gpu,dl_gpu,dZ_gpu,dmu_gpu,dS_gpu,dL_dpsi1_gpu,psi1_gpu, np.float64(variance),l_gpu,Z_gpu,mu_gpu,S_gpu, np.int32(N), np.int32(M), np.int32(Q), block=(self.threadnum,1,1), grid=(self.blocknum,1))
# print np.abs(dvar_psi1-dvar_gpu.get().sum(axis=-1)).max()
# print np.abs(dl_psi1-dl_gpu.get().sum(axis=-1)).max()
# print np.abs(dmu_psi1-dmu_gpu.get().sum(axis=-1)).max()
# print np.abs(dS_psi1-dS_gpu.get().sum(axis=-1)).max()
# print np.abs(dZ_psi1-dZ_gpu.get()).max()
# self.reset_derivative()
self.g_psi2compDer(dvar_gpu,dl_gpu,dZ_gpu,dmu_gpu,dS_gpu,dL_dpsi2_gpu,psi2n_gpu, np.float64(variance),l_gpu,Z_gpu,mu_gpu,S_gpu, np.int32(N), np.int32(M), np.int32(Q), block=(self.threadnum,1,1), grid=(self.blocknum,1))
# print np.abs(dvar_psi2-dvar_gpu.get().sum(axis=-1)).max()
# print np.abs(dl_psi2-dl_gpu.get().sum(axis=-1)).max()
# print np.abs(dmu_psi2-dmu_gpu.get().sum(axis=-1)).max()
# print np.abs(dS_psi2-dS_gpu.get().sum(axis=-1)).max()
# print np.abs(dZ_psi2-dZ_gpu.get()).max()
dL_dvar = np.sum(dL_dpsi0) + dvar_gpu.get().sum()
dL_dmu = dmu_gpu.get().sum(axis=-1)
dL_dS = dS_gpu.get().sum(axis=-1)
dL_dvar = np.sum(dL_dpsi0) + gpuarray.sum(dvar_gpu).get()
sum_axis(grad_mu_gpu,dmu_gpu,N*Q,self.blocknum)
dL_dmu = grad_mu_gpu.get()
sum_axis(grad_S_gpu,dS_gpu,N*Q,self.blocknum)
dL_dS = grad_S_gpu.get()
dL_dZ = dZ_gpu.get()
if ARD:
dL_dlengscale = dl_gpu.get().sum(axis=-1)
sum_axis(grad_l_gpu,dl_gpu,Q,self.blocknum)
dL_dlengscale = grad_l_gpu.get()
else:
dL_dlengscale = dl_gpu.get().sum()
dL_dlengscale = gpuarray.sum(dl_gpu).get()
# print np.abs(dL_dlengscale - dl_psi1-dl_psi2).max()
#
# dL_dvar = np.sum(dL_dpsi0) + dvar_psi1 + dvar_psi2
#
# dL_dlengscale = dl_psi1 + dl_psi2
# if not ARD:
# dL_dlengscale = dL_dlengscale.sum()
#
# dL_dmu = dmu_psi1 + dmu_psi2
# dL_dS = dS_psi1 + dS_psi2
# dL_dZ = dZ_psi1 + dZ_psi2
return dL_dvar, dL_dlengscale, dL_dZ, dL_dmu, dL_dS
def psicomputations(variance, lengthscale, Z, variational_posterior):
"""
Z - MxQ
mu - NxQ
S - NxQ
gamma - NxQ
"""
# here are the "statistics" for psi0, psi1 and psi2
# Produced intermediate results:
# _psi1 NxM
mu = variational_posterior.mean
S = variational_posterior.variance
psi0 = np.empty(mu.shape[0])
psi0[:] = variance
psi1 = _psi1computations(variance, lengthscale, Z, mu, S)
psi2 = _psi2computations(variance, lengthscale, Z, mu, S).sum(axis=0)
return psi0, psi1, psi2
def __psi1computations(variance, lengthscale, Z, mu, S):
"""
Z - MxQ
mu - NxQ
S - NxQ
gamma - NxQ
"""
# here are the "statistics" for psi1
# Produced intermediate results:
# _psi1 NxM
lengthscale2 = np.square(lengthscale)
# psi1
_psi1_logdenom = np.log(S/lengthscale2+1.).sum(axis=-1) # N
_psi1_log = (_psi1_logdenom[:,None]+np.einsum('nmq,nq->nm',np.square(mu[:,None,:]-Z[None,:,:]),1./(S+lengthscale2)))/(-2.)
_psi1 = variance*np.exp(_psi1_log)
return _psi1
def __psi2computations(variance, lengthscale, Z, mu, S):
"""
Z - MxQ
mu - NxQ
S - NxQ
gamma - NxQ
"""
# here are the "statistics" for psi2
# Produced intermediate results:
# _psi2 MxM
lengthscale2 = np.square(lengthscale)
_psi2_logdenom = np.log(2.*S/lengthscale2+1.).sum(axis=-1)/(-2.) # N
_psi2_exp1 = (np.square(Z[:,None,:]-Z[None,:,:])/lengthscale2).sum(axis=-1)/(-4.) #MxM
Z_hat = (Z[:,None,:]+Z[None,:,:])/2. #MxMxQ
denom = 1./(2.*S+lengthscale2)
_psi2_exp2 = -(np.square(mu)*denom).sum(axis=-1)[:,None,None]+2.*np.einsum('nq,moq,nq->nmo',mu,Z_hat,denom)-np.einsum('moq,nq->nmo',np.square(Z_hat),denom)
_psi2 = variance*variance*np.exp(_psi2_logdenom[:,None,None]+_psi2_exp1[None,:,:]+_psi2_exp2)
return _psi2
def psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, variance, lengthscale, Z, variational_posterior):
ARD = (len(lengthscale)!=1)
dvar_psi1, dl_psi1, dZ_psi1, dmu_psi1, dS_psi1 = _psi1compDer(dL_dpsi1, variance, lengthscale, Z, variational_posterior.mean, variational_posterior.variance)
dvar_psi2, dl_psi2, dZ_psi2, dmu_psi2, dS_psi2 = _psi2compDer(dL_dpsi2, variance, lengthscale, Z, variational_posterior.mean, variational_posterior.variance)
dL_dvar = np.sum(dL_dpsi0) + dvar_psi1 + dvar_psi2
dL_dlengscale = dl_psi1 + dl_psi2
if not ARD:
dL_dlengscale = dL_dlengscale.sum()
dL_dmu = dmu_psi1 + dmu_psi2
dL_dS = dS_psi1 + dS_psi2
dL_dZ = dZ_psi1 + dZ_psi2
return dL_dvar, dL_dlengscale, dL_dZ, dL_dmu, dL_dS
def _psi1compDer(dL_dpsi1, variance, lengthscale, Z, mu, S):
"""
dL_dpsi1 - NxM
Z - MxQ
mu - NxQ
S - NxQ
gamma - NxQ
"""
# here are the "statistics" for psi1
# Produced intermediate results: dL_dparams w.r.t. psi1
# _dL_dvariance 1
# _dL_dlengthscale Q
# _dL_dZ MxQ
# _dL_dgamma NxQ
# _dL_dmu NxQ
# _dL_dS NxQ
lengthscale2 = np.square(lengthscale)
_psi1 = _psi1computations(variance, lengthscale, Z, mu, S)
Lpsi1 = dL_dpsi1*_psi1
Zmu = Z[None,:,:]-mu[:,None,:] # NxMxQ
denom = 1./(S+lengthscale2)
Zmu2_denom = np.square(Zmu)*denom[:,None,:] #NxMxQ
_dL_dvar = Lpsi1.sum()/variance
_dL_dmu = np.einsum('nm,nmq,nq->nq',Lpsi1,Zmu,denom)
_dL_dS = np.einsum('nm,nmq,nq->nq',Lpsi1,(Zmu2_denom-1.),denom)/2.
_dL_dZ = -np.einsum('nm,nmq,nq->mq',Lpsi1,Zmu,denom)
_dL_dl = np.einsum('nm,nmq,nq->q',Lpsi1,(Zmu2_denom+(S/lengthscale2)[:,None,:]),denom*lengthscale)
return _dL_dvar, _dL_dl, _dL_dZ, _dL_dmu, _dL_dS
def _psi2compDer(dL_dpsi2, variance, lengthscale, Z, mu, S):
"""
Z - MxQ
mu - NxQ
S - NxQ
gamma - NxQ
dL_dpsi2 - MxM
"""
# here are the "statistics" for psi2
# Produced the derivatives w.r.t. psi2:
# _dL_dvariance 1
# _dL_dlengthscale Q
# _dL_dZ MxQ
# _dL_dgamma NxQ
# _dL_dmu NxQ
# _dL_dS NxQ
lengthscale2 = np.square(lengthscale)
denom = 1./(2*S+lengthscale2)
denom2 = np.square(denom)
_psi2 = _psi2computations(variance, lengthscale, Z, mu, S) # NxMxM
Lpsi2 = dL_dpsi2[None,:,:]*_psi2
Lpsi2sum = np.einsum('nmo->n',Lpsi2) #N
Lpsi2Z = np.einsum('nmo,oq->nq',Lpsi2,Z) #NxQ
Lpsi2Z2 = np.einsum('nmo,oq,oq->nq',Lpsi2,Z,Z) #NxQ
Lpsi2Z2p = np.einsum('nmo,mq,oq->nq',Lpsi2,Z,Z) #NxQ
Lpsi2Zhat = Lpsi2Z
Lpsi2Zhat2 = (Lpsi2Z2+Lpsi2Z2p)/2
_dL_dvar = Lpsi2sum.sum()*2/variance
_dL_dmu = (-2*denom) * (mu*Lpsi2sum[:,None]-Lpsi2Zhat)
_dL_dS = (2*np.square(denom))*(np.square(mu)*Lpsi2sum[:,None]-2*mu*Lpsi2Zhat+Lpsi2Zhat2) - denom*Lpsi2sum[:,None]
_dL_dZ = -np.einsum('nmo,oq->oq',Lpsi2,Z)/lengthscale2+np.einsum('nmo,oq->mq',Lpsi2,Z)/lengthscale2+ \
2*np.einsum('nmo,nq,nq->mq',Lpsi2,mu,denom) - np.einsum('nmo,nq,mq->mq',Lpsi2,denom,Z) - np.einsum('nmo,oq,nq->mq',Lpsi2,Z,denom)
_dL_dl = 2*lengthscale* ((S/lengthscale2*denom+np.square(mu*denom))*Lpsi2sum[:,None]+(Lpsi2Z2-Lpsi2Z2p)/(2*np.square(lengthscale2))-
(2*mu*denom2)*Lpsi2Zhat+denom2*Lpsi2Zhat2).sum(axis=0)
return _dL_dvar, _dL_dl, _dL_dZ, _dL_dmu, _dL_dS
_psi1computations = Cacher(__psi1computations, limit=1)
_psi2computations = Cacher(__psi2computations, limit=1)

View file

@ -29,6 +29,8 @@ class RBF(Stationary):
self.psicomp = PSICOMP_RBF()
if self.useGPU:
self.psicomp = PSICOMP_RBF_GPU()
else:
self.psicomp = PSICOMP_RBF()
def K_of_r(self, r):
return self.variance * np.exp(-0.5 * r**2)
@ -41,41 +43,22 @@ class RBF(Stationary):
#---------------------------------------#
def psi0(self, Z, variational_posterior):
if self.useGPU:
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[0]
else:
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[0]
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[0]
def psi1(self, Z, variational_posterior):
if self.useGPU:
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[1]
else:
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[1]
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[1]
def psi2(self, Z, variational_posterior):
if self.useGPU:
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[2]
else:
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[2]
return self.psicomp.psicomputations(self.variance, self.lengthscale, Z, variational_posterior)[2]
def update_gradients_expectations(self, dL_dpsi0, dL_dpsi1, dL_dpsi2, Z, variational_posterior):
if self.useGPU:
dL_dvar, dL_dlengscale = self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[:2]
self.variance.gradient = dL_dvar
self.lengthscale.gradient = dL_dlengscale
else:
dL_dvar, dL_dlengscale = self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[:2]
self.variance.gradient = dL_dvar
self.lengthscale.gradient = dL_dlengscale
dL_dvar, dL_dlengscale = self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[:2]
self.variance.gradient = dL_dvar
self.lengthscale.gradient = dL_dlengscale
def gradients_Z_expectations(self, dL_dpsi0, dL_dpsi1, dL_dpsi2, Z, variational_posterior):
if self.useGPU:
return self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[2]
else:
return self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[2]
return self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[2]
def gradients_qX_expectations(self, dL_dpsi0, dL_dpsi1, dL_dpsi2, Z, variational_posterior):
if self.useGPU:
return self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[3:]
else:
return self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[3:]
return self.psicomp.psiDerivativecomputations(dL_dpsi0, dL_dpsi1, dL_dpsi2, self.variance, self.lengthscale, Z, variational_posterior)[3:]