def main(num_epochs=500):
# Load the dataset
print("Loading data...")
#X_train, y_train, X_val, y_val, X_test, y_test= pull_data()
trainX, trainY, valX, valY, testX, testY = pull_data()
trainX = normalize(trainX.reshape(trainX.shape[0],1, DIM, DIM))
valX = normalize(valX.reshape(valX.shape[0],1, DIM, DIM))
testX = normalize(testX.reshape(testX.shape[0],1, DIM, DIM))
trainY = trainY - 1
valY = valY - 1
testY = testY - 1
trainX, trainY = shuffle(trainX, trainY)
valX, valY = shuffle(valX, valY)
testX, testY = shuffle(testX, testY)
# Prepare Theano variables for inputs and targets
input_var = T.tensor4('inputs')
output_var = T.ivector('targets')
model = build_cnn(input_var)
print "[X] CNN defining its goals."
model_params = lasagne.layers.get_all_params(model, trainable=True)
sh_lr = theano.shared(lasagne.utils.floatX(LEARNING_RATE))
#why do we want to compute output expressions for model and input_var???
noisy_output = lasagne.layers.get_output(model, input_var, deterministic=False)
true_output = lasagne.layers.get_output(model, input_var, deterministic=True)
noisy_prediction = T.argmax(noisy_output, 1)
true_prediction = T.argmax(true_output, 1)
l2_loss = regularize_layer_params(model, l2)*L2_REG
## Loss expression
noisy_cost = T.mean(T.nnet.categorical_crossentropy(noisy_output, output_var)) + l2_loss
true_cost = T.mean(T.nnet.categorical_crossentropy(true_output, output_var)) + l2_loss
## error values
noisy_error = 1.0 - T.mean(lasagne.objectives.categorical_accuracy(noisy_output, output_var))
true_error = 1.0 - T.mean(lasagne.objectives.categorical_accuracy(true_output, output_var))
## stochastic gradient descent updates
#updates = lasagne.updates.sgd(noisy_cost, model_params, learning_rate=sh_lr)
##stochastic gradient descent with Nesterov momentum
updates = lasagne.updates.nesterov_momentum(
noisy_cost, model_params, learning_rate=sh_lr, momentum=0.99)
train = theano.function([input_var,output_var], [noisy_cost, noisy_error],
updates=updates,
allow_input_downcast=True)
get_score = theano.function([input_var,output_var], [true_cost, true_error],
allow_input_downcast=True)
best_validation_cost = np.inf
best_iter = 0
n_train_batches = int(np.ceil(trainX.shape[0] / float(BATCH_SIZE)))
plot_iters = []
plot_train_cost = []
plot_train_error = []
plot_valid_cost = []
plot_valid_error = []
plot_test_cost = []
plot_test_error = []
epoch = 0
print "[X] CNN begins its training."
try:
while True:
epoch = epoch + 1
for minibatch_index in xrange(n_train_batches):
iter = (epoch - 1) * n_train_batches + minibatch_index
if iter % 100 == 0:
print "[O] Training at iteration %d." % iter
cost_ij = train(trainX[minibatch_index*BATCH_SIZE:np.minimum((minibatch_index+1)*BATCH_SIZE, trainX.shape[0])],
trainY[minibatch_index*BATCH_SIZE:np.minimum((minibatch_index+1)*BATCH_SIZE, trainY.shape[0])])
if (iter+1) % VALIDATION_FREQUENCY == 0:
train_cost, train_error = get_score(trainX, trainY)
valid_cost, valid_error = get_score(valX, valY)
test_cost, test_error = get_score(testX, testY)
plot_train_cost.append(train_cost)
plot_train_error.append(train_error)
plot_valid_cost.append(valid_cost)
plot_valid_error.append(valid_error)
plot_test_cost.append(test_cost)
plot_test_error.append(test_error)
plot_iters.append(iter)
## plotting functions
if not os.path.exists(FIGURE_SAVE_DIR):
os.makedirs(FIGURE_SAVE_DIR)
plot_curves(plot_iters, plot_train_cost, plot_valid_cost, 'Training Cost', 'Validation Cost', 'train_val_cost.pdf')
plot_curves(plot_iters, plot_train_error, plot_valid_error, 'Training Error', 'Validation Error', 'train_val_error.pdf')
#plot_cm(train_pred, trainY, 'Confusion Matrix on the Training Set', 'cm_train.pdf')
#plot_cm(valid_pred, valY, 'Confusion Matrix on the Validation Set', 'cm_valid.pdf')
#plot_cm(test_pred, testY, 'Confusion Matrix on the Test Set', 'cm_test.pdf')
print "--> Epoch %i, minibatch %i/%i has training true cost \t %f." % (epoch, minibatch_index+1, n_train_batches, train_cost)
print "--> Epoch %i, minibatch %i/%i has validation true cost \t %f and error of \t %f %%." % (epoch, minibatch_index+1, n_train_batches, valid_cost, valid_error)
if valid_cost < best_validation_cost:
print "----> New best score found!"
print "--> Test cost of %f and test error of %f." % (test_cost, test_error)
if not os.path.exists(PARAM_SAVE_DIR):
os.makedirs(PARAM_SAVE_DIR)
for f in glob.glob(PARAM_SAVE_DIR+'/*'):
os.remove(f)
all_param_values = lasagne.layers.get_all_param_values(model)
joblib.dump(all_param_values, os.path.join(PARAM_SAVE_DIR, 'params.pkl'))
print "----> Parameters saved."
best_validation_cost = valid_cost
best_iter = iter
except KeyboardInterrupt:
pass
end_time = timeit.default_timer()
print "--> Best validation score of %f." % best_validation_cost
print "--> Total runtime %.2f minutes." % ((end_time-start_time) / 60.)
print "[X] Saving the scores."
joblib.dump(plot_iters, os.path.join(PARAM_SAVE_DIR, "iters.pkl"))
joblib.dump(plot_train_cost, os.path.join(PARAM_SAVE_DIR, "train_cost.pkl"))
joblib.dump(plot_train_error, os.path.join(PARAM_SAVE_DIR, "train_error.pkl"))
joblib.dump(plot_valid_cost, os.path.join(PARAM_SAVE_DIR, "valid_cost.pkl"))
joblib.dump(plot_valid_error, os.path.join(PARAM_SAVE_DIR, "valid_error.pkl"))
joblib.dump(plot_test_cost, os.path.join(PARAM_SAVE_DIR, "test_cost.pkl"))
joblib.dump(plot_test_error, os.path.join(PARAM_SAVE_DIR, "test_error.pkl"))
PARAM_SAVE_DIR = "./params"
# Data params:
IMAGE_WIDTH = 41
IMAGE_HEIGHT = 41
N_CLASSES = 15
# Conv_net params:
NUM_EPOCHS = 8000
LEARNING_RATE = 0.005
if __name__ == "__main__":
trainX, trainY, valX, valY, testX, testY = pull_data()
print "Building the conv net..."
layer0 = lasagne.layers.InputLayer(shape=(None, 1, IMAGE_WIDTH, IMAGE_HEIGHT))
layer1 = lasagne.layers.Conv2DLayer(layer0, num_filters=16, filter_size=(8, 8))
layer2 = lasagne.layers.MaxPool2DLayer(layer1, pool_size=(2, 2))
layer3 = lasagne.layers.Conv2DLayer(layer2, num_filters=48, filter_size=(5, 5))
layer4 = lasagne.layers.MaxPool2DLayer(layer3, pool_size=(2, 2))
layer5 = lasagne.layers.Conv2DLayer(layer4, num_filters=60, filter_size=(2, 2))
layer6 = lasagne.layers.MaxPool2DLayer(layer5, pool_size=(2, 2))
layer7 = lasagne.layers.DenseLayer(layer6, num_units=256, W=lasagne.init.GlorotUniform())
layer8 = lasagne.layers.DenseLayer(
layer7, num_units=N_CLASSES, nonlinearity=lasagne.nonlinearities.softmax, W=lasagne.init.GlorotUniform()
)
model = layer8
