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546 lines
28 KiB
Python
546 lines
28 KiB
Python
# Copyright (c) 2012, GPy authors (see AUTHORS.txt).
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# Licensed under the BSD 3-clause license (see LICENSE.txt)
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from posterior import Posterior
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from ...util.linalg import jitchol, backsub_both_sides, tdot, dtrtrs
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from ...util import diag
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from ...core.parameterization.variational import VariationalPosterior
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import numpy as np
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from ...util.misc import param_to_array
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from . import LatentFunctionInference
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log_2_pi = np.log(2*np.pi)
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from ...util import gpu_init
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try:
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import scikits.cuda.linalg as culinalg
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import pycuda.gpuarray as gpuarray
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from scikits.cuda import cublas
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from ...util.linalg_gpu import logDiagSum, strideSum, mul_bcast, sum_axis, outer_prod, mul_bcast_first, join_prod
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except:
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pass
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class VarDTC_GPU(LatentFunctionInference):
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"""
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An object for inference when the likelihood is Gaussian, but we want to do sparse inference.
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The function self.inference returns a Posterior object, which summarizes
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the posterior.
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For efficiency, we sometimes work with the cholesky of Y*Y.T. To save repeatedly recomputing this, we cache it.
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"""
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const_jitter = np.float64(1e-6)
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def __init__(self, batchsize=None, gpu_memory=4., limit=1):
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self.batchsize = batchsize
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self.gpu_memory = gpu_memory
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self.midRes = {}
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self.batch_pos = 0 # the starting position of the current mini-batch
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self.cublas_handle = gpu_init.cublas_handle
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# Initialize GPU caches
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self.gpuCache = None
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def _initGPUCache(self, kern, num_inducing, input_dim, output_dim, Y):
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ndata = Y.shape[0]
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if self.batchsize==None:
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self.batchsize = self._estimateBatchSize(kern, ndata, num_inducing, input_dim, output_dim)
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if self.gpuCache == None:
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self.gpuCache = {# inference_likelihood
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'Kmm_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'Lm_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'ones_gpu' :gpuarray.empty(num_inducing, np.float64,order='F'),
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'LL_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'b_gpu' :gpuarray.empty((num_inducing,output_dim),np.float64,order='F'),
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'v_gpu' :gpuarray.empty((num_inducing,output_dim),np.float64,order='F'),
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'vvt_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'KmmInvPsi2LLInvT_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'KmmInvPsi2P_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'dL_dpsi2R_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'dL_dKmm_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'psi1Y_gpu' :gpuarray.empty((num_inducing,output_dim),np.float64,order='F'),
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'psi2_gpu' :gpuarray.empty((num_inducing,num_inducing),np.float64,order='F'),
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'beta_gpu' :gpuarray.empty((ndata,),np.float64,order='F'),
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'YT_gpu' :gpuarray.to_gpu(np.asfortranarray(Y.T)), # DxN
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'betaYT_gpu' :gpuarray.empty(Y.T.shape,np.float64,order='F'), # DxN
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'psi2_t_gpu' :gpuarray.empty((num_inducing*num_inducing*self.batchsize),np.float64,order='F'),
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# inference_minibatch
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'dL_dpsi0_gpu' :gpuarray.empty((self.batchsize,),np.float64,order='F'),
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'dL_dpsi1_gpu' :gpuarray.empty((self.batchsize,num_inducing),np.float64,order='F'),
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'dL_dpsi2_gpu' :gpuarray.empty((self.batchsize,num_inducing,num_inducing),np.float64,order='F'),
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'dL_dthetaL_gpu' :gpuarray.empty((self.batchsize,),np.float64,order='F'),
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'betapsi1_gpu' :gpuarray.empty((self.batchsize,num_inducing),np.float64,order='F'),
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'thetaL_t_gpu' :gpuarray.empty((self.batchsize,),np.float64,order='F'),
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'betaYT2_gpu' :gpuarray.empty((output_dim,self.batchsize),np.float64,order='F'),
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'psi0p_gpu' :gpuarray.empty((self.batchsize,),np.float64,order='F'),
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'psi1p_gpu' :gpuarray.empty((self.batchsize,num_inducing),np.float64,order='F'),
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'psi2p_gpu' :gpuarray.empty((self.batchsize,num_inducing,num_inducing),np.float64,order='F'),
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}
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self.gpuCache['ones_gpu'].fill(1.0)
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YT_gpu = self.gpuCache['YT_gpu']
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self._trYYT = cublas.cublasDdot(self.cublas_handle, YT_gpu.size, YT_gpu.gpudata, 1, YT_gpu.gpudata, 1)
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def _estimateMemoryOccupation(self, N, M, D):
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"""
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Estimate the best batch size.
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N - the number of total datapoints
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M - the number of inducing points
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D - the number of observed (output) dimensions
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return: the constant memory size, the memory occupation of batchsize=1
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unit: GB
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"""
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return (M+9.*M*M+3*M*D+N+2.*N*D)*8./1024./1024./1024., (4.+3.*M+D+3.*M*M)*8./1024./1024./1024.
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def _estimateBatchSize(self, kern, N, M, Q, D):
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"""
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Estimate the best batch size.
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N - the number of total datapoints
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M - the number of inducing points
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D - the number of observed (output) dimensions
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return: the constant memory size, the memory occupation of batchsize=1
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unit: GB
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"""
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if kern.useGPU:
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x0,x1 = kern.psicomp.estimateMemoryOccupation(N,M,Q)
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else:
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x0, x1 = 0.,0.
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y0, y1 = self._estimateMemoryOccupation(N, M, D)
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opt_batchsize = min(int((self.gpu_memory-y0-x0)/(x1+y1)), N)
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return opt_batchsize
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def _get_YYTfactor(self, Y):
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"""
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find a matrix L which satisfies LLT = YYT.
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Note that L may have fewer columns than Y.
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"""
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N, D = Y.shape
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if (N>=D):
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return param_to_array(Y)
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else:
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return jitchol(tdot(Y))
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def inference_likelihood(self, kern, X, Z, likelihood, Y):
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"""
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The first phase of inference:
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Compute: log-likelihood, dL_dKmm
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Cached intermediate results: Kmm, KmmInv,
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"""
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num_inducing, input_dim = Z.shape[0], Z.shape[1]
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num_data, output_dim = Y.shape
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self._initGPUCache(kern, num_inducing, input_dim, output_dim, Y)
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if isinstance(X, VariationalPosterior):
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uncertain_inputs = True
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else:
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uncertain_inputs = False
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#see whether we've got a different noise variance for each datum
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beta = 1./np.fmax(likelihood.variance, 1e-6)
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het_noise = beta.size > 1
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trYYT = self._trYYT
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psi1Y_gpu = self.gpuCache['psi1Y_gpu']
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psi2_gpu = self.gpuCache['psi2_gpu']
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beta_gpu = self.gpuCache['beta_gpu']
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YT_gpu = self.gpuCache['YT_gpu']
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betaYT_gpu = self.gpuCache['betaYT_gpu']
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psi2_t_gpu = self.gpuCache['psi2_t_gpu']
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if het_noise:
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beta_gpu.set(np.asfortranarray(beta))
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mul_bcast(betaYT_gpu,beta_gpu,YT_gpu,beta_gpu.size)
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YRY_full = cublas.cublasDdot(self.cublas_handle, YT_gpu.size, betaYT_gpu.gpudata, 1, YT_gpu.gpudata, 1)
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else:
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beta_gpu.fill(beta)
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betaYT_gpu.fill(0.)
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cublas.cublasDaxpy(self.cublas_handle, betaYT_gpu.size, beta, YT_gpu.gpudata, 1, betaYT_gpu.gpudata, 1)
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YRY_full = trYYT*beta
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if kern.useGPU:
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psi1Y_gpu.fill(0.)
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psi2_gpu.fill(0.)
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psi0_full = 0
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for n_start in xrange(0,num_data,self.batchsize):
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n_end = min(self.batchsize+n_start, num_data)
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ndata = n_end - n_start
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X_slice = X[n_start:n_end]
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beta_gpu_slice = beta_gpu[n_start:n_end]
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betaYT_gpu_slice = betaYT_gpu[:,n_start:n_end]
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if ndata==self.batchsize:
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psi2_t_gpu_slice = psi2_t_gpu
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else:
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psi2_t_gpu_slice = psi2_t_gpu[:num_inducing*num_inducing*ndata]
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if uncertain_inputs:
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psi0p_gpu = kern.psi0(Z, X_slice)
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psi1p_gpu = kern.psi1(Z, X_slice)
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psi2p_gpu = kern.psi2(Z, X_slice)
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else:
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psi0p_gpu = kern.Kdiag(X_slice)
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psi1p_gpu = kern.K(X_slice, Z)
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cublas.cublasDgemm(self.cublas_handle, 'T', 'T', num_inducing, output_dim, ndata, 1.0, psi1p_gpu.gpudata, ndata, betaYT_gpu_slice.gpudata, output_dim, 1.0, psi1Y_gpu.gpudata, num_inducing)
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if het_noise:
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psi0_full += cublas.cublasDdot(self.cublas_handle, psi0p_gpu.size, beta_gpu_slice.gpudata, 1, psi0p_gpu.gpudata, 1)
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else:
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psi0_full += gpuarray.sum(psi0p_gpu).get()
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if uncertain_inputs:
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if het_noise:
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mul_bcast(psi2_t_gpu_slice,beta_gpu_slice,psi2p_gpu,beta_gpu_slice.size)
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sum_axis(psi2_gpu,psi2_t_gpu_slice,1,ndata)
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else:
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sum_axis(psi2_gpu,psi2p_gpu,1,ndata)
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else:
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if het_noise:
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psi1_t_gpu = psi2_t_gpu_slice[:,num_inducing*ndata]
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mul_bcast(psi1_t_gpu,beta_gpu_slice,psi1p_gpu,beta_gpu_slice.size)
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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)
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else:
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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)
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if not het_noise:
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psi0_full *= beta
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if uncertain_inputs:
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cublas.cublasDscal(self.cublas_handle, psi2_gpu.size, beta, psi2_gpu.gpudata, 1)
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else:
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psi2_full = np.zeros((num_inducing,num_inducing),order='F')
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psi1Y_full = np.zeros((num_inducing,output_dim),order='F') # MxD
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psi0_full = 0
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# YRY_full = 0
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for n_start in xrange(0,num_data,self.batchsize):
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n_end = min(self.batchsize+n_start, num_data)
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Y_slice = Y[n_start:n_end]
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X_slice = X[n_start:n_end]
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if uncertain_inputs:
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psi0 = kern.psi0(Z, X_slice)
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psi1 = kern.psi1(Z, X_slice)
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psi2 = kern.psi2(Z, X_slice)
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else:
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psi0 = kern.Kdiag(X_slice)
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psi1 = kern.K(X_slice, Z)
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if het_noise:
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beta_slice = beta[n_start:n_end]
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psi0_full += (beta_slice*psi0).sum()
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psi1Y_full += np.dot(psi1.T,beta_slice[:,None]*Y_slice) # MxD
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# YRY_full += (beta_slice*np.square(Y_slice).sum(axis=-1)).sum()
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else:
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psi0_full += psi0.sum()
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psi1Y_full += np.dot(psi1.T,Y_slice) # MxD
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if uncertain_inputs:
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if het_noise:
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psi2_full += np.einsum('n,nmo->mo',beta_slice,psi2)
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else:
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psi2_full += psi2.sum(axis=0)
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else:
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if het_noise:
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psi2_full += np.einsum('n,nm,no->mo',beta_slice,psi1,psi1)
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else:
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psi2_full += tdot(psi1.T)
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if not het_noise:
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psi0_full *= beta
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psi1Y_full *= beta
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psi2_full *= beta
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# YRY_full = trYYT*beta
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psi1Y_gpu.set(psi1Y_full)
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psi2_gpu.set(psi2_full)
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#======================================================================
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# Compute Common Components
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#======================================================================
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Kmm = kern.K(Z).copy()
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Kmm_gpu = self.gpuCache['Kmm_gpu']
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Kmm_gpu.set(np.asfortranarray(Kmm))
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diag.add(Kmm, self.const_jitter)
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ones_gpu = self.gpuCache['ones_gpu']
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cublas.cublasDaxpy(self.cublas_handle, num_inducing, self.const_jitter, ones_gpu.gpudata, 1, Kmm_gpu.gpudata, num_inducing+1)
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# assert np.allclose(Kmm, Kmm_gpu.get())
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# Lm = jitchol(Kmm)
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#
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Lm_gpu = self.gpuCache['Lm_gpu']
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cublas.cublasDcopy(self.cublas_handle, Kmm_gpu.size, Kmm_gpu.gpudata, 1, Lm_gpu.gpudata, 1)
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culinalg.cho_factor(Lm_gpu,'L')
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# print np.abs(np.tril(Lm)-np.tril(Lm_gpu.get())).max()
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# Lambda = Kmm+psi2_full
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# LL = jitchol(Lambda)
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#
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Lambda_gpu = self.gpuCache['LL_gpu']
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cublas.cublasDcopy(self.cublas_handle, Kmm_gpu.size, Kmm_gpu.gpudata, 1, Lambda_gpu.gpudata, 1)
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cublas.cublasDaxpy(self.cublas_handle, psi2_gpu.size, np.float64(1.0), psi2_gpu.gpudata, 1, Lambda_gpu.gpudata, 1)
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LL_gpu = Lambda_gpu
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culinalg.cho_factor(LL_gpu,'L')
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# print np.abs(np.tril(LL)-np.tril(LL_gpu.get())).max()
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# b,_ = dtrtrs(LL, psi1Y_full)
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# bbt_cpu = np.square(b).sum()
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#
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b_gpu = self.gpuCache['b_gpu']
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cublas.cublasDcopy(self.cublas_handle, b_gpu.size, psi1Y_gpu.gpudata, 1, b_gpu.gpudata, 1)
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cublas.cublasDtrsm(self.cublas_handle , 'L', 'L', 'N', 'N', num_inducing, output_dim, np.float64(1.0), LL_gpu.gpudata, num_inducing, b_gpu.gpudata, num_inducing)
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bbt = cublas.cublasDdot(self.cublas_handle, b_gpu.size, b_gpu.gpudata, 1, b_gpu.gpudata, 1)
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# print np.abs(bbt-bbt_cpu)
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# v,_ = dtrtrs(LL.T,b,lower=False)
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# vvt = np.einsum('md,od->mo',v,v)
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# LmInvPsi2LmInvT = backsub_both_sides(Lm,psi2_full,transpose='right')
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#
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v_gpu = self.gpuCache['v_gpu']
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cublas.cublasDcopy(self.cublas_handle, v_gpu.size, b_gpu.gpudata, 1, v_gpu.gpudata, 1)
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cublas.cublasDtrsm(self.cublas_handle , 'L', 'L', 'T', 'N', num_inducing, output_dim, np.float64(1.0), LL_gpu.gpudata, num_inducing, v_gpu.gpudata, num_inducing)
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vvt_gpu = self.gpuCache['vvt_gpu']
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cublas.cublasDgemm(self.cublas_handle, 'N', 'T', num_inducing, num_inducing, output_dim, np.float64(1.0), v_gpu.gpudata, num_inducing, v_gpu.gpudata, num_inducing, np.float64(0.), vvt_gpu.gpudata, num_inducing)
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LmInvPsi2LmInvT_gpu = self.gpuCache['KmmInvPsi2LLInvT_gpu']
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cublas.cublasDcopy(self.cublas_handle, psi2_gpu.size, psi2_gpu.gpudata, 1, LmInvPsi2LmInvT_gpu.gpudata, 1)
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cublas.cublasDtrsm(self.cublas_handle , 'L', 'L', 'N', 'N', num_inducing, num_inducing, np.float64(1.0), Lm_gpu.gpudata, num_inducing, LmInvPsi2LmInvT_gpu.gpudata, num_inducing)
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cublas.cublasDtrsm(self.cublas_handle , 'r', 'L', 'T', 'N', num_inducing, num_inducing, np.float64(1.0), Lm_gpu.gpudata, num_inducing, LmInvPsi2LmInvT_gpu.gpudata, num_inducing)
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#tr_LmInvPsi2LmInvT = cublas.cublasDasum(self.cublas_handle, num_inducing, LmInvPsi2LmInvT_gpu.gpudata, num_inducing+1)
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tr_LmInvPsi2LmInvT = float(strideSum(LmInvPsi2LmInvT_gpu, num_inducing+1).get())
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# print np.abs(vvt-vvt_gpu.get()).max()
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# print np.abs(np.trace(LmInvPsi2LmInvT)-tr_LmInvPsi2LmInvT)
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# Psi2LLInvT = dtrtrs(LL,psi2_full)[0].T
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# LmInvPsi2LLInvT= dtrtrs(Lm,Psi2LLInvT)[0]
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# KmmInvPsi2LLInvT = dtrtrs(Lm,LmInvPsi2LLInvT,trans=True)[0]
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# KmmInvPsi2P = dtrtrs(LL,KmmInvPsi2LLInvT.T, trans=True)[0].T
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#
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KmmInvPsi2LLInvT_gpu = LmInvPsi2LmInvT_gpu # Reuse GPU memory (size:MxM)
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cublas.cublasDcopy(self.cublas_handle, psi2_gpu.size, psi2_gpu.gpudata, 1, KmmInvPsi2LLInvT_gpu.gpudata, 1)
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cublas.cublasDtrsm(self.cublas_handle , 'L', 'L', 'N', 'N', num_inducing, num_inducing, np.float64(1.0), Lm_gpu.gpudata, num_inducing, KmmInvPsi2LLInvT_gpu.gpudata, num_inducing)
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cublas.cublasDtrsm(self.cublas_handle , 'r', 'L', 'T', 'N', num_inducing, num_inducing, np.float64(1.0), LL_gpu.gpudata, num_inducing, KmmInvPsi2LLInvT_gpu.gpudata, num_inducing)
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cublas.cublasDtrsm(self.cublas_handle , 'L', 'L', 'T', 'N', num_inducing, num_inducing, np.float64(1.0), Lm_gpu.gpudata, num_inducing, KmmInvPsi2LLInvT_gpu.gpudata, num_inducing)
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KmmInvPsi2P_gpu = self.gpuCache['KmmInvPsi2P_gpu']
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cublas.cublasDcopy(self.cublas_handle, KmmInvPsi2LLInvT_gpu.size, KmmInvPsi2LLInvT_gpu.gpudata, 1, KmmInvPsi2P_gpu.gpudata, 1)
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cublas.cublasDtrsm(self.cublas_handle , 'r', 'L', 'N', 'N', num_inducing, num_inducing, np.float64(1.0), LL_gpu.gpudata, num_inducing, KmmInvPsi2P_gpu.gpudata, num_inducing)
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# print np.abs(KmmInvPsi2P-KmmInvPsi2P_gpu.get()).max()
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# dL_dpsi2R = (output_dim*KmmInvPsi2P - vvt)/2. # dL_dpsi2 with R inside psi2
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#
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dL_dpsi2R_gpu = self.gpuCache['dL_dpsi2R_gpu']
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cublas.cublasDcopy(self.cublas_handle, vvt_gpu.size, vvt_gpu.gpudata, 1, dL_dpsi2R_gpu.gpudata, 1)
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cublas.cublasDaxpy(self.cublas_handle, KmmInvPsi2P_gpu.size, np.float64(-output_dim), KmmInvPsi2P_gpu.gpudata, 1, dL_dpsi2R_gpu.gpudata, 1)
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cublas.cublasDscal(self.cublas_handle, dL_dpsi2R_gpu.size, np.float64(-0.5), dL_dpsi2R_gpu.gpudata, 1)
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# print np.abs(dL_dpsi2R_gpu.get()-dL_dpsi2R).max()
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|
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#======================================================================
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# Compute log-likelihood
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#======================================================================
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if het_noise:
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logL_R = -np.log(beta).sum()
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else:
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logL_R = -num_data*np.log(beta)
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# logL_old = -(output_dim*(num_data*log_2_pi+logL_R+psi0_full-np.trace(LmInvPsi2LmInvT))+YRY_full-bbt)/2.-output_dim*(-np.log(np.diag(Lm)).sum()+np.log(np.diag(LL)).sum())
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|
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logdetKmm = float(logDiagSum(Lm_gpu,num_inducing+1).get())
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logdetLambda = float(logDiagSum(LL_gpu,num_inducing+1).get())
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logL = -(output_dim*(num_data*log_2_pi+logL_R+psi0_full-tr_LmInvPsi2LmInvT)+YRY_full-bbt)/2.+output_dim*(logdetKmm-logdetLambda)
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# print np.abs(logL_old - logL)
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#======================================================================
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# Compute dL_dKmm
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#======================================================================
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|
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# dL_dKmm = -(output_dim*np.einsum('md,od->mo',KmmInvPsi2LLInvT,KmmInvPsi2LLInvT) + vvt)/2.
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|
#
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dL_dKmm_gpu = self.gpuCache['dL_dKmm_gpu']
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cublas.cublasDgemm(self.cublas_handle, 'N', 'T', num_inducing, num_inducing, num_inducing, np.float64(1.0), KmmInvPsi2LLInvT_gpu.gpudata, num_inducing, KmmInvPsi2LLInvT_gpu.gpudata, num_inducing, np.float64(0.), dL_dKmm_gpu.gpudata, num_inducing)
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|
cublas.cublasDaxpy(self.cublas_handle, dL_dKmm_gpu.size, np.float64(1./output_dim), vvt_gpu.gpudata, 1, dL_dKmm_gpu.gpudata, 1)
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|
cublas.cublasDscal(self.cublas_handle, dL_dKmm_gpu.size, np.float64(-output_dim/2.), dL_dKmm_gpu.gpudata, 1)
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|
# print np.abs(dL_dKmm - dL_dKmm_gpu.get()).max()
|
|
|
|
#======================================================================
|
|
# Compute the Posterior distribution of inducing points p(u|Y)
|
|
#======================================================================
|
|
|
|
post = Posterior(woodbury_inv=KmmInvPsi2P_gpu.get(), woodbury_vector=v_gpu.get(), K=Kmm_gpu.get(), mean=None, cov=None, K_chol=Lm_gpu.get())
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|
|
|
return logL, dL_dKmm_gpu.get(), post
|
|
|
|
def inference_minibatch(self, kern, X, Z, likelihood, Y):
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|
"""
|
|
The second phase of inference: Computing the derivatives over a minibatch of Y
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|
Compute: dL_dpsi0, dL_dpsi1, dL_dpsi2, dL_dthetaL
|
|
return a flag showing whether it reached the end of Y (isEnd)
|
|
"""
|
|
|
|
num_data, output_dim = Y.shape
|
|
num_inducing = Z.shape[0]
|
|
|
|
if isinstance(X, VariationalPosterior):
|
|
uncertain_inputs = True
|
|
else:
|
|
uncertain_inputs = False
|
|
|
|
beta = 1./np.fmax(likelihood.variance, 1e-6)
|
|
het_noise = beta.size > 1
|
|
|
|
n_start = self.batch_pos
|
|
n_end = min(self.batchsize+n_start, num_data)
|
|
if n_end==num_data:
|
|
isEnd = True
|
|
self.batch_pos = 0
|
|
else:
|
|
isEnd = False
|
|
self.batch_pos = n_end
|
|
|
|
nSlice = n_end-n_start
|
|
X_slice = X[n_start:n_end]
|
|
|
|
if kern.useGPU:
|
|
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)
|
|
psi2p_gpu = self.gpuCache['psi2p_gpu']
|
|
if psi2p_gpu.shape[0] > nSlice:
|
|
psi2p_gpu = psi2p_gpu.ravel()[:nSlice*num_inducing*num_inducing].reshape(nSlice,num_inducing,num_inducing)
|
|
else:
|
|
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)
|
|
|
|
psi0p_gpu = self.gpuCache['psi0p_gpu']
|
|
psi1p_gpu = self.gpuCache['psi1p_gpu']
|
|
psi2p_gpu = self.gpuCache['psi2p_gpu']
|
|
if psi0p_gpu.shape[0] > nSlice:
|
|
psi0p_gpu = psi0p_gpu[:nSlice]
|
|
psi1p_gpu = psi1p_gpu.ravel()[:nSlice*num_inducing].reshape(nSlice,num_inducing)
|
|
psi2p_gpu = psi2p_gpu.ravel()[:nSlice*num_inducing*num_inducing].reshape(nSlice,num_inducing,num_inducing)
|
|
psi0p_gpu.set(np.asfortranarray(psi0))
|
|
psi1p_gpu.set(np.asfortranarray(psi1))
|
|
if uncertain_inputs:
|
|
psi2p_gpu.set(np.asfortranarray(psi2))
|
|
|
|
#======================================================================
|
|
# Prepare gpu memory
|
|
#======================================================================
|
|
|
|
dL_dpsi2R_gpu = self.gpuCache['dL_dpsi2R_gpu']
|
|
v_gpu = self.gpuCache['v_gpu']
|
|
betaYT_gpu = self.gpuCache['betaYT_gpu']
|
|
beta_gpu = self.gpuCache['beta_gpu']
|
|
dL_dpsi0_gpu = self.gpuCache['dL_dpsi0_gpu']
|
|
dL_dpsi1_gpu = self.gpuCache['dL_dpsi1_gpu']
|
|
dL_dpsi2_gpu = self.gpuCache['dL_dpsi2_gpu']
|
|
dL_dthetaL_gpu = self.gpuCache['dL_dthetaL_gpu']
|
|
psi2R_gpu = self.gpuCache['psi2_t_gpu'][:nSlice*num_inducing*num_inducing].reshape(nSlice,num_inducing,num_inducing)
|
|
betapsi1_gpu = self.gpuCache['betapsi1_gpu']
|
|
thetaL_t_gpu = self.gpuCache['thetaL_t_gpu']
|
|
betaYT2_gpu = self.gpuCache['betaYT2_gpu']
|
|
|
|
betaYT_gpu_slice = betaYT_gpu[:,n_start:n_end]
|
|
beta_gpu_slice = beta_gpu[n_start:n_end]
|
|
|
|
# Adjust to the batch size
|
|
if dL_dpsi0_gpu.shape[0] > nSlice:
|
|
betaYT2_gpu = betaYT2_gpu[:,:nSlice]
|
|
dL_dpsi0_gpu = dL_dpsi0_gpu.ravel()[:nSlice]
|
|
dL_dpsi1_gpu = dL_dpsi1_gpu.ravel()[:nSlice*num_inducing].reshape(nSlice,num_inducing)
|
|
dL_dpsi2_gpu = dL_dpsi2_gpu.ravel()[:nSlice*num_inducing*num_inducing].reshape(nSlice,num_inducing,num_inducing)
|
|
dL_dthetaL_gpu = dL_dthetaL_gpu.ravel()[:nSlice]
|
|
psi2R_gpu = psi2R_gpu.ravel()[:nSlice*num_inducing*num_inducing].reshape(nSlice,num_inducing,num_inducing)
|
|
thetaL_t_gpu = thetaL_t_gpu.ravel()[:nSlice]
|
|
betapsi1_gpu = betapsi1_gpu.ravel()[:nSlice*num_inducing].reshape(nSlice,num_inducing)
|
|
|
|
mul_bcast(betapsi1_gpu,beta_gpu_slice,psi1p_gpu,beta_gpu_slice.size)
|
|
|
|
#======================================================================
|
|
# Compute dL_dpsi
|
|
#======================================================================
|
|
|
|
dL_dpsi0_gpu.fill(0.)
|
|
cublas.cublasDaxpy(self.cublas_handle, dL_dpsi0_gpu.size, output_dim/(-2.), beta_gpu_slice.gpudata, 1, dL_dpsi0_gpu.gpudata, 1)
|
|
|
|
cublas.cublasDgemm(self.cublas_handle, 'T', 'T', nSlice, num_inducing, output_dim, 1.0, betaYT_gpu_slice.gpudata, output_dim, v_gpu.gpudata, num_inducing, 0., dL_dpsi1_gpu.gpudata, nSlice)
|
|
|
|
if uncertain_inputs:
|
|
outer_prod(dL_dpsi2_gpu,beta_gpu_slice,dL_dpsi2R_gpu,beta_gpu_slice.size)
|
|
else:
|
|
cublas.cublasDgemm(self.cublas_handle, 'N', 'N', nSlice, num_inducing, output_dim, 1.0, betapsi1_gpu.gpudata, nSlice, dL_dpsi2R_gpu.gpudata, num_inducing, 1.0, dL_dpsi1_gpu.gpudata, nSlice)
|
|
|
|
#======================================================================
|
|
# Compute dL_dthetaL
|
|
#======================================================================
|
|
|
|
if not uncertain_inputs:
|
|
join_prod(psi2p_gpu,psi1p_gpu,psi1p_gpu,nSlice,num_inducing)
|
|
|
|
mul_bcast_first(psi2R_gpu,dL_dpsi2R_gpu,psi2p_gpu,nSlice)
|
|
|
|
|
|
dL_dthetaL_gpu.fill(0.)
|
|
|
|
cublas.cublasDcopy(self.cublas_handle, betaYT_gpu_slice.size, betaYT_gpu_slice.gpudata, 1, betaYT2_gpu.gpudata, 1)
|
|
mul_bcast(betaYT2_gpu,betaYT2_gpu,betaYT2_gpu,betaYT2_gpu.size)
|
|
cublas.cublasDscal(self.cublas_handle, betaYT2_gpu.size, 0.5, betaYT2_gpu.gpudata, 1)
|
|
sum_axis(dL_dthetaL_gpu, betaYT2_gpu, 1, output_dim)
|
|
|
|
cublas.cublasDaxpy(self.cublas_handle, dL_dthetaL_gpu.size, output_dim/(-2.0), beta_gpu_slice.gpudata, 1, dL_dthetaL_gpu.gpudata, 1)
|
|
cublas.cublasDcopy(self.cublas_handle, beta_gpu_slice.size, beta_gpu_slice.gpudata, 1, thetaL_t_gpu.gpudata, 1)
|
|
mul_bcast(thetaL_t_gpu,thetaL_t_gpu,thetaL_t_gpu,thetaL_t_gpu.size)
|
|
mul_bcast(thetaL_t_gpu,thetaL_t_gpu,psi0p_gpu,thetaL_t_gpu.size)
|
|
cublas.cublasDaxpy(self.cublas_handle, dL_dthetaL_gpu.size, output_dim/2.0, thetaL_t_gpu.gpudata, 1, dL_dthetaL_gpu.gpudata, 1)
|
|
|
|
thetaL_t_gpu.fill(0.)
|
|
sum_axis(thetaL_t_gpu, psi2R_gpu, nSlice, num_inducing*num_inducing)
|
|
mul_bcast(thetaL_t_gpu,thetaL_t_gpu,beta_gpu_slice,thetaL_t_gpu.size)
|
|
mul_bcast(thetaL_t_gpu,thetaL_t_gpu,beta_gpu_slice,thetaL_t_gpu.size)
|
|
cublas.cublasDaxpy(self.cublas_handle, dL_dthetaL_gpu.size, -1.0, thetaL_t_gpu.gpudata, 1, dL_dthetaL_gpu.gpudata, 1)
|
|
|
|
cublas.cublasDgemm(self.cublas_handle, 'T', 'T', output_dim, nSlice, num_inducing, -1.0, v_gpu.gpudata, num_inducing, betapsi1_gpu.gpudata, nSlice, 0.0, betaYT2_gpu.gpudata, output_dim)
|
|
mul_bcast(betaYT2_gpu,betaYT2_gpu,betaYT_gpu_slice,betaYT2_gpu.size)
|
|
sum_axis(dL_dthetaL_gpu, betaYT2_gpu, 1, output_dim)
|
|
|
|
if kern.useGPU:
|
|
dL_dpsi0 = dL_dpsi0_gpu
|
|
dL_dpsi1 = dL_dpsi1_gpu
|
|
else:
|
|
dL_dpsi0 = dL_dpsi0_gpu.get()
|
|
dL_dpsi1 = dL_dpsi1_gpu.get()
|
|
if uncertain_inputs:
|
|
if kern.useGPU:
|
|
dL_dpsi2 = dL_dpsi2_gpu
|
|
else:
|
|
dL_dpsi2 = dL_dpsi2_gpu.get()
|
|
if het_noise:
|
|
dL_dthetaL = dL_dthetaL_gpu.get()
|
|
else:
|
|
dL_dthetaL = gpuarray.sum(dL_dthetaL_gpu).get()
|
|
if uncertain_inputs:
|
|
grad_dict = {'dL_dpsi0':dL_dpsi0,
|
|
'dL_dpsi1':dL_dpsi1,
|
|
'dL_dpsi2':dL_dpsi2,
|
|
'dL_dthetaL':dL_dthetaL}
|
|
else:
|
|
grad_dict = {'dL_dKdiag':dL_dpsi0,
|
|
'dL_dKnm':dL_dpsi1,
|
|
'dL_dthetaL':dL_dthetaL}
|
|
|
|
return isEnd, (n_start,n_end), grad_dict
|
|
|