def continuity(weights):
"""
:param weights: nxd array where n = neurons and d = weights
:return: continuity value based on simulated cortical sheet
"""
# determine number of neurons
neurons = weights.shape[0]
# get distance matrix
distances = distMat(neurons, d=neurons)
# get similarity value between all pairwise neurons
similarity = np.dot(weights.T, weights)
# calculate continuity
c = np.multiply(distances, similarity)
return c
def continuity(weights):
"""
:param weights: nxd array where n = neurons and d = weights
:return: continuity value based on simulated cortical sheet
"""
# determine number of neurons
neurons = weights.shape[0]
# get distance matrix
distances = distMat(neurons, d=neurons)
# get similarity value between all pairwise neurons
similarity = np.dot(weights.T, weights)
# calculate continuity
c = np.multiply(distances, similarity)
return c
print "finding optimal neuronal positions..."
optimal_positions = {}
minimal_wiring_length = {}
# initial_distance = distMat(weights.shape[0])
for model in model_names:
entity = None
optimal_positions[model] = []
minimal_wiring_length[model] = []
if convolutional == 'n':
entity = final_weights[model].shape[0]
elif convolutional == 'y':
entity = train_labels.shape[1]
for neuron in xrange(entity):
weights = final_weights[model][neuron, :]
distances = distMat(len(weights), d=None, kind='euclidean', inverted='n')
wiring_lengths = np.dot(np.abs(weights), distances.T) # should this be transposed?
minimum_wiring = np.min(wiring_lengths)
XY = np.argmin(wiring_lengths)
optimal_positions[model].append(XY) # [X, Y] # todo: convert to coordinates
minimal_wiring_length[model].append(minimum_wiring)
# w = t.fvector()
# d_mat = t.fmatrix()
# # d_mat = t.fvector()
#
# x = theano.shared(np.asarray(np.floor(np.sqrt(final_weights[model].shape[0]) / 2), dtype=theano.config.floatX))
# y = theano.shared(np.asarray(np.floor(np.sqrt(final_weights[model].shape[0]) / 2), dtype=theano.config.floatX))
#
def main():
# get the folders in "saved" and select most recent
base_path = os.path.dirname(__file__)
folder_path = os.path.join(base_path, "saved")
folders = os.listdir(folder_path)
folder = folders[3] # select most frequent folder # -1
# load in activation data
print "loading in the data..."
file_path = os.path.join(folder_path, folder, "concatenated_activations.mat")
# data = loadmat(file_path)['master'] # [examples, neurons, image-space]
data = h5py.File(file_path, 'r')['master']
data = np.array(data)
data = data.T
print data.shape
# TODO: scale and normalize data
# load in data labels
file_path = os.path.join(base_path, "data", "CIFAR_data.mat")
train_labels = loadmat(file_path)['y']
# augment training_labels to account for extra examples in image-space
y_labels = numpy.matlib.repmat(train_labels, 1, data.shape[2]).reshape((data.shape[0] * data.shape[2], 1))
# convert labels to binary vector
lb = LabelBinarizer()
lb.fit(train_labels)
y_labels = lb.transform(y_labels)
# perform neuron-wise regularized linear regression to obtain coefficients
print "performing neuron-wise regularized linear regression..."
neurons = data.shape[1]
classes = 10
coefficients = np.zeros((neurons, classes))
for neuron in xrange(data.shape[1]):
print neuron
x = data[:, neuron, :].reshape(data.shape[0] * data.shape[2], 1)
clf = Ridge(alpha=1.0)
clf.fit(y_labels, x)
coefficients[neuron, :] = clf.coef_
# save the coefficients
c = {'coefficients': coefficients}
coefficient_path = os.path.join(folder_path, folder, "coefficients.mat")
savemat(coefficient_path, c)
# visualize histogram of coefficients
pl.hist(np.abs(coefficients.flatten()), bins=30)
pl.title('Frequency Distribution of Coefficient Values')
pl.xlabel('Coefficient Value')
pl.ylabel('Frequency')
pl.show()
# todo: find the N sparse filters from the data
model = ['SparseFilter']
n_filters = 10
input_dim = coefficients.shape[1]
dimensions = ([n_filters, input_dim],) # number of filters equals number of classes
pool = None
group = None
step = None
learn_rate = .001
opt = 'GD'
convolution = 'n'
test = 'n'
batch_size = 1000
random = 'n'
weights = None
iterations = 1000
channels = 1
n_batches = coefficients.shape[0] / batch_size
if n_batches == 0:
n_batches = 1
# construct the network
print "building model..."
model = sf.Network(
model_type=model,
weight_dims=dimensions,
p=pool,
group_size=group,
step=step,
lr=learn_rate,
opt=opt,
c=convolution,
test=test,
batch_size=batch_size,
random=random,
weights=weights
)
# compile the training, output, and test functions for the network
print "compiling theano functions..."
train, outputs, test = model.training_functions(np.float32(coefficients))
# train the sparse filtering network
print "training network..."
t = time.time()
cost = {}
weights = {}
layer = None
for l in xrange(model.n_layers):
layer = 'layer' + str(l)
cost_layer = []
w = None
# iterate over training epochs
for epoch in xrange(iterations):
# go though [mini]batches
for batch_index in xrange(n_batches):
c, w = train[l](index=batch_index)
cost_layer.append(c)
print("Layer %i cost at epoch %i and batch %i: %f" % (l + 1, epoch, batch_index, c))
# add layer cost and weights to the dictionaries
cost[layer] = cost_layer
weights[layer] = w
# calculate and display elapsed training time
elapsed = time.time() - t
print('Elapsed training time: %f' % elapsed)
# order the components based on their activations (proxy for amount of variance explained)
activations, _, _, _, _, _ = outputs[0](np.float32(coefficients))
activations_summed = np.sum(np.abs(activations), axis=1)
index = np.argsort(activations_summed)
weights[layer] = weights[layer][index]
# save the components (each column represents a component with each element the value for each object category)
components_path = os.path.join(folder_path, folder, 'weights.mat')
savemat(components_path, weights)
# plot the cost function over time
visualize.plotCost(cost)
# visualize the components with respect to the object categories
pl.imshow(weights[layer], interpolation='nearest')
pl.title('Sparse Filtering Components')
pl.xlabel('Weights')
pl.ylabel('Filters')
pl.xticks(np.arange(1, 10, 10))
pl.yticks(np.arange(1, 10, 10))
pl.show()
# project the components back onto the cortical sheet (i.e., the dot product between each neuron's model
# coefficients and each component)
projections = activations
visualize.drawplots(projections.T, color='gray', convolution=convolution,
pad=0, examples=None, channels=channels)
# todo: compare the similarity of adjacent neurons of different distances and visualize
distance_measure = 'cityblock'
max_distance = cdist(np.atleast_2d([0, 0]), np.atleast_2d([np.sqrt(neurons), np.sqrt(neurons)]), distance_measure)
continuity_data = np.zeros((1, max_distance))
distances = distMat(neurons, d=neurons * 100, kind=distance_measure)
pl.imshow(distances)
pl.show()
divisor = np.zeros((1, max_distance))
for i in xrange(neurons):
for j in xrange(neurons):
correlation = pearsonr(coefficients[i, :].T, coefficients[j, :].T)
d = distances[i, j]
print d, correlation
continuity_data[0, d] += correlation[0]
divisor[0, d] += 1
c += 1
correlation_averages = continuity_data / divisor
correlation_averages = correlation_averages[~np.isnan(correlation_averages)]
# correlation_std = np.std(continuity_data, axis=0)
# correlation_std = correlation_std[~np.isnan(correlation_std)] # todo: allow computation of std
temp_std = np.linspace(.2, .1, len(correlation_averages))
print temp_std
print correlation_averages
hypothetical_averages = [1., 0.7, 0.5, 0.4, 0.28, 0.21, 0.15, 0.09, 0.07, 0.05]
hypothetical_stds = np.linspace(.07, .1, len(correlation_averages) - 1)
fig = visualize.plot_mean_std(correlation_averages[0:10], temp_std[0:10], hypothetical_averages, hypothetical_stds)
fig.show()
optimal_positions = {}
minimal_wiring_length = {}
# initial_distance = distMat(weights.shape[0])
for model in model_names:
entity = None
optimal_positions[model] = []
minimal_wiring_length[model] = []
if convolutional == 'n':
entity = final_weights[model].shape[0]
elif convolutional == 'y':
entity = train_labels.shape[1]
for neuron in xrange(entity):
weights = final_weights[model][neuron, :]
distances = distMat(len(weights),
d=None,
kind='euclidean',
inverted='n')
wiring_lengths = np.dot(np.abs(weights),
distances.T) # should this be transposed?
minimum_wiring = np.min(wiring_lengths)
XY = np.argmin(wiring_lengths)
optimal_positions[model].append(
XY) # [X, Y] # todo: convert to coordinates
minimal_wiring_length[model].append(minimum_wiring)
# w = t.fvector()
# d_mat = t.fmatrix()
# # d_mat = t.fvector()
#
