Mercurial > ift6266
changeset 276:727ed56fad12
Add reworked code for convolutional auto-encoder.
author | Arnaud Bergeron <abergeron@gmail.com> |
---|---|
date | Mon, 22 Mar 2010 13:33:29 -0400 |
parents | 7b4507295eba |
children | 20ebc1f2a9fe |
files | deep/convolutional_dae/scdae.py deep/convolutional_dae/sgd_opt.py |
diffstat | 2 files changed, 281 insertions(+), 0 deletions(-) [+] |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/deep/convolutional_dae/scdae.py Mon Mar 22 13:33:29 2010 -0400 @@ -0,0 +1,229 @@ +from pynnet import * +# use hacks also +from pynnet.utils import * + +import numpy +import theano +import theano.tensor as T + +from itertools import izip + +class cdae(LayerStack): + def __init__(self, filter_size, num_filt, num_in, subsampling, corruption, + dtype, img_shape): + LayerStack.__init__(self, [ConvAutoencoder(filter_size=filter_size, + num_filt=num_filt, + num_in=num_in, + noisyness=corruption, + dtype=dtype, + image_shape=img_shape), + MaxPoolLayer(subsampling)]) + + def build(self, input): + LayerStack.build(self, input) + self.cost = self.layers[0].cost + +def cdae_out_size(in_size, filt_size, num_filt, num_in, subs): + out = [None] * 3 + out[0] = num_filt + out[1] = (in_size[1]-filt_size[0]+1)/subs[0] + out[2] = (in_size[2]-filt_size[1]+1)/subs[1] + return out + +def scdae(in_size, num_in, filter_sizes, num_filts, + subsamplings, corruptions, dtype): + layers = [] + old_nfilt = 1 + for fsize, nfilt, subs, corr in izip(filter_sizes, num_filts, + subsamplings, corruptions): + layers.append(cdae(fsize, nfilt, old_nfilt, subs, corr, dtype, + (num_in, in_size[0], in_size[1], in_size[2]))) + in_size = cdae_out_size(in_size, fsize, nfilt, old_nfilt, subs) + old_nfilt = nfilt + return LayerStack(layers), in_size + +def mlp(layer_sizes, dtype): + layers = [] + old_size = layer_sizes[0] + for size in layer_sizes[1:]: + layers.append(SimpleLayer(old_size, size, activation=nlins.tanh, + dtype=dtype)) + old_size = size + return LayerStack(layers) + +def scdae_net(in_size, num_in, filter_sizes, num_filts, subsamplings, + corruptions, layer_sizes, out_size, dtype, batch_size): + rl1 = ReshapeLayer((None,)+in_size) + ls, outs = scdae(in_size, num_in, filter_sizes, num_filts, subsamplings, + corruptions, dtype) + outs = numpy.prod(outs) + rl2 = ReshapeLayer((None, outs)) + layer_sizes = [outs]+layer_sizes + ls2 = mlp(layer_sizes, dtype) + lrl = SimpleLayer(layer_sizes[-1], out_size, activation=nlins.sigmoid) + return NNet([rl1, ls, rl2, ls2, lrl], error=errors.nll) + +def build_funcs(batch_size, img_size, filter_sizes, num_filters, subs, + noise, mlp_sizes, out_size, dtype, pretrain_lr, train_lr): + + n = scdae_net((1,)+img_size, batch_size, filter_sizes, num_filters, subs, + noise, mlp_sizes, out_size, dtype, batch_size) + x = T.fmatrix('x') + y = T.ivector('y') + + def pretrainfunc(net, alpha): + up = trainers.get_updates(net.params, net.cost, alpha) + return theano.function([x], net.cost, updates=up) + + def trainfunc(net, alpha): + up = trainers.get_updates(net.params, net.cost, alpha) + return theano.function([x, y], net.cost, updates=up) + + n.build(x, y) + pretrain_funcs_opt = [pretrainfunc(l, pretrain_lr) for l in n.layers[1].layers] + trainf_opt = trainfunc(n, train_lr) + evalf_opt = theano.function([x, y], errors.class_error(n.output, y)) + + clear_imgshape(n) + n.build(x, y) + pretrain_funcs_reg = [pretrainfunc(l, 0.01) for l in n.layers[1].layers] + trainf_reg = trainfunc(n, 0.1) + evalf_reg = theano.function([x, y], errors.class_error(n.output, y)) + + def select_f(f1, f2, bsize): + def f(x): + if x.shape[0] == bsize: + return f1(x) + else: + return f2(x) + return f + + pretrain_funcs = [select_f(p_opt, p_reg, batch_size) for p_opt, p_reg in zip(pretrain_funcs_opt, pretrain_funcs_reg)] + + def select_f2(f1, f2, bsize): + def f(x, y): + if x.shape[0] == bsize: + return f1(x, y) + else: + return f2(x, y) + return f + + trainf = select_f2(trainf_opt, trainf_reg, batch_size) + evalf = select_f2(evalf_opt, evalf_reg, batch_size) + return pretrain_funcs, trainf, evalf + +def do_pretrain(pretrain_funcs, pretrain_epochs): + for f in pretrain_funcs: + for i in xrange(pretrain_epochs): + f() + +def massage_funcs(batch_size, dset, pretrain_funcs, trainf, evalf): + def pretrain_f(f): + def res(): + for x, y in dset.train(batch_size): + print "pretrain:", f(x) + return res + + pretrain_fs = map(pretrain_f, pretrain_funcs) + + def train_f(f, dsetf): + def dset_it(): + while True: + for x, y in dsetf(batch_size): + yield f(x, y) + it = dset_it() + return lambda: it.next() + + train = train_f(trainf, dset.train) + + def eval_f(f, dsetf): + def res(): + c = 0 + i = 0 + for x, y in dsetf(batch_size): + i += x.shape[0] + c += f(x, y)*x.shape[0] + return c/i + return res + + test = eval_f(evalf, dset.test) + valid = eval_f(evalf, dset.valid) + + return pretrain_fs, train, valid, test + +def run_exp(state, channel): + from ift6266 import datasets + from sgd_opt import sgd_opt + import sys, time + + channel.save() + + # params: bsize, pretrain_lr, train_lr, nfilts1, nfilts2, nftils3, nfilts4 + # pretrain_rounds + + dset = dataset.nist_all() + + nfilts = [] + if state.nfilts1 != 0: + nfilts.append(state.nfilts1) + if state.nfilts2 != 0: + nfilts.append(state.nfilts2) + if state.nfilts3 != 0: + nfilts.append(state.nfilts3) + if state.nfilts4 != 0: + nfilts.append(state.nfilts4) + + fsizes = [(5,5)]*len(nfilts) + subs = [(2,2)]*len(nfilts) + noise = [state.noise]*len(nfilts) + + pretrain_funcs, trainf, evalf = build_funcs( + img_size=(32, 32), + batch_size=state.bsize, + filter_sizes=fsizes, + num_filters=nfilts, + subs=subs, + noise=noise, + mlp_sizes=[state.mlp_sz], + out_size=62, + dtype=numpy.float32, + pretrain_lr=state.pretrain_lr, + train_lr=state.train_lr) + + pretrain_fs, train, valid, test = massage_funcs( + state.bsize, dset, pretrain_funcs, trainf, evalf) + + do_pretrain(pretrain_fs, state.pretrain_rounds) + + sgd_opt(train, valid, test, training_epochs=100000, patience=10000, + patience_increase=2., improvement_threshold=0.995, + validation_frequency=2500) + +if __name__ == '__main__': + from ift6266 import datasets + from sgd_opt import sgd_opt + import sys, time + + batch_size = 100 + dset = datasets.mnist(200) + + pretrain_funcs, trainf, evalf = build_funcs( + img_size = (28, 28), + batch_size=batch_size, filter_sizes=[(5,5), (5,5)], + num_filters=[4, 3], subs=[(2,2), (2,2)], noise=[0.2, 0.2], + mlp_sizes=[500], out_size=10, dtype=numpy.float32, + pretrain_lr=0.01, train_lr=0.1) + + pretrain_fs, train, valid, test = massage_funcs( + batch_size, dset, pretrain_funcs, trainf, evalf) + + print "pretraining ...", + sys.stdout.flush() + start = time.time() + do_pretrain(pretrain_fs, 0) + end = time.time() + print "done (in", end-start, "s)" + + sgd_opt(train, valid, test, training_epochs=1000, patience=1000, + patience_increase=2., improvement_threshold=0.995, + validation_frequency=500)
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/deep/convolutional_dae/sgd_opt.py Mon Mar 22 13:33:29 2010 -0400 @@ -0,0 +1,52 @@ +import time +import sys + +def sgd_opt(train, valid, test, training_epochs=10000, patience=10000, + patience_increase=2., improvement_threshold=0.995, + validation_frequency=None): + + if validation_frequency is None: + validation_frequency = patience/2 + + start_time = time.clock() + + best_params = None + best_validation_loss = float('inf') + test_score = 0. + + start_time = time.clock() + + for epoch in xrange(1, training_epochs+1): + train() + + if epoch % validation_frequency == 0: + this_validation_loss = valid() + print('epoch %i, validation error %f %%' % \ + (epoch, this_validation_loss*100.)) + + # if we got the best validation score until now + if this_validation_loss < best_validation_loss: + + #improve patience if loss improvement is good enough + if this_validation_loss < best_validation_loss * \ + improvement_threshold : + patience = max(patience, epoch * patience_increase) + + # save best validation score and epoch number + best_validation_loss = this_validation_loss + best_epoch = epoch + + # test it on the test set + test_score = test() + print((' epoch %i, test error of best model %f %%') % + (epoch, test_score*100.)) + + if patience <= epoch: + break + + end_time = time.clock() + print(('Optimization complete with best validation score of %f %%,' + 'with test performance %f %%') % + (best_validation_loss * 100., test_score*100.)) + print ('The code ran for %f minutes' % ((end_time-start_time)/60.)) +