def predict():
classifier = cPickle.load(file('best_model_logistic.pkl','r'))
datasets = LF.load_cifar()
test_set_x, test_set_y = datasets[1]
test_set_x = test_set_x.get_value()
predict_model = theano.function(inputs=[classifier.input], outputs=classifier.errors(test_set_y))
test_score = predict_model(test_set_x)
print "Predicted accuracy for the test set: %.2f%%" % (test_score*100.)
def sgd_optimization(learning_rate=0.1, n_epochs=1000, batch_size=200):
datasets = LF.load_cifar()
train_set_x, train_set_y = datasets[0]
test_set_x, test_set_y = datasets[1]
n_train_batches = train_set_x.get_value(borrow=True).shape[0]/batch_size
n_test_batches = test_set_x.get_value(borrow=True).shape[0]/batch_size
print '... building the model'
index = T.lscalar()
x = T.matrix('x')
y = T.ivector('y')
classifier = LogisticRegression(input=x, n_in=1024, n_out=10)
test_model = theano.function(
inputs=[index],
outputs=classifier.errors(y),
givens={
x: test_set_x[index * batch_size: (index + 1) * batch_size],
y: test_set_y[index * batch_size: (index + 1) * batch_size]
}
)
cost = classifier.neg_log_hood(y)
g_W = T.grad(cost=cost, wrt=classifier.W)
g_b = T.grad(cost=cost, wrt=classifier.b)
updates = [(classifier.W, classifier.W - learning_rate * g_W),
(classifier.b, classifier.b - learning_rate * g_b)]
train_model = theano.function(
inputs=[index],
outputs=cost,
updates=updates,
givens={
x: train_set_x[index * batch_size: (index + 1) * batch_size],
y: train_set_y[index * batch_size: (index + 1) * batch_size]
}
)
###############
# TRAIN MODEL #
###############
print '... training the model'
test_score = 0.
start_time = timeit.default_timer()
prev_avg_cost = 0
done_looping = False
epoch = 0
while (epoch < n_epochs) and (not done_looping):
epoch = epoch + 1
train_cost_vector=[train_model(i) for i in xrange(n_train_batches)]
train_cost = numpy.mean(train_cost_vector)/batch_size
test_losses = [test_model(i) for i in xrange(n_test_batches)]
test_score = numpy.mean(test_losses)
print 'epoch %d with train cost %.2f, test error %.2f%%'% (epoch,train_cost,test_score*100.)
if train_cost<1920:
test_losses_opt = [test_model(i) for i in xrange(n_test_batches)]
test_score_opt = numpy.mean(test_losses_opt)
# save the best model
f = file('best_model_logistic.pkl', 'w')
cPickle.dump(classifier, f, protocol=cPickle.HIGHEST_PROTOCOL)
f.close()
break
prev_avg_cost=train_cost
end_time = timeit.default_timer()
print 'Optimization complete with test performance %.2f %%' %(test_score_opt*100.)
print 'The code runs for %.1fs' % (end_time - start_time)
#############################################################
# Created by Yinan Xu, 12/06/2015 #
# Copyright @ Yinan Xu #
#############################################################
import Image
from utils import tile_raster_images
import load_CIFAR as LF
datasets = LF.load_cifar()
train_set_x, train_set_y = datasets[0]
xx = train_set_x.get_value()[0:100]
image = Image.fromarray(
tile_raster_images(
X=xx,
img_shape=(32, 32),
tile_shape=(10, 10),
tile_spacing=(1, 1)
)
)
image.save('first_100_images.png')
print "save images successful"