def nn_save(w, b, path="./", file_prefix=""):
"""Temporary function for saving neural network weights to disk
"""
layer_count = len(w)
for i in range(layer_count):
np.save(path + file_prefix + "L" + repr(i + 1) + "_w.npy", gnp.as_numpy_array(w[i]))
np.save(path + file_prefix + "L" + repr(i + 1) + "_b.npy", gnp.as_numpy_array(b[i]))
def partition_function(self, batch_size, prec):
"""The exact value of Z calculated with precision prec.
Only feasible for small number of hidden units."""
with decimal.localcontext() as ctx:
if prec != 0:
ctx.prec = prec
batches = ml.common.util.pack_in_batches(all_states(self.n_hid),
batch_size)
if prec != 0:
s = decimal.Decimal(0)
else:
allfhes = np.array([])
seen_samples = 0L
total_samples = 2L**self.n_hid
for hid in batches:
print >>stderr, "%i / %i \r" % (seen_samples, total_samples),
fhes = self.free_hidden_energy(hid)
if prec != 0:
for fhe in gp.as_numpy_array(fhes):
p = decimal.Decimal(-fhe).exp()
s += p
else:
allfhes = np.concatenate((allfhes,
-gp.as_numpy_array(fhes)))
seen_samples += hid.shape[0]
if prec != 0:
return s
else:
return logsum(allfhes)
def tuple_to_array(t):
x = t[0]
y = t[1]
out = np.zeros((x.shape[0], x.shape[1], x.shape[2], 2))
out[:,:,:,0] = gp.as_numpy_array(x)
out[:,:,:,1] = gp.as_numpy_array(y)
return out
def plot_samples(samples, samples_force=None, twod=False, width=28, height=28):
samples = gp.as_numpy_array(samples)
samples = np.asarray(samples)
if samples_force is not None:
samples_force = gp.as_numpy_array(samples_force)
samples_force = np.asarray(samples_force)
if (not twod and samples.ndim == 1) or (twod and samples.ndim == 2):
if twod:
height = samples.shape[0]
width = samples.shape[1]
return _plot_one_sample(samples, samples_force, twod=twod,
width=width, height=height)
else:
n_samples = samples.shape[0]
if twod:
height = samples.shape[1]
width = samples.shape[2]
out = np.zeros((height, width*n_samples, 3))
for s in range(n_samples):
if samples_force is not None:
o = _plot_one_sample(samples[s], samples_force[s], twod=twod,
width=width, height=height)
else:
o = _plot_one_sample(samples[s], None, twod=twod,
width=width, height=height)
out[:, s*width : (s+1)*width, :] = o
return out
def output_errors(self, n_plot=100000, alpha=0.05,
plot_only_guilty_samples=True):
# output statistics
acc_low, acc_high, acc_mle = \
self.generator_accuracy_interval(alpha=alpha)
print "Error probability: %g [%g, %g]" % (1-acc_mle,
1-acc_high, 1-acc_low)
fe_low, fe_high = self.fe_interval(alpha=alpha)
print "Free energy: [%g, %g]" % (fe_low, fe_high)
if self.tmpl_X is not None:
# collect incorrectly classified samples
tmpl_X = gp.as_numpy_array(self.tmpl_X)
gen_X = gp.as_numpy_array(self.gen_X)
if plot_only_guilty_samples:
s = self.guilty_samples
else:
s = self.incorrect_samples
err_tmpl_X = tmpl_X[s,:]
err_gen_X = gen_X[s,:]
err_tmpl_Z = self.tmpl_Z[s]
err_gen_Z = np.asarray(self.gen_Z[s], dtype='uint8')
# output
print "Misclassified samples:"
print "True labels: ", err_tmpl_Z[0:n_plot]
print "Generated labels: ", err_gen_Z[0:n_plot]
if err_tmpl_X.shape[0] > 0:
myplt = np.concatenate((common.util.plot_samples(err_tmpl_X[0:n_plot]),
ml.common.util.plot_samples(err_gen_X[0:n_plot])))
plt.imshow(myplt, interpolation='none')
def free_energies_during_gibbs_sampling(self, x, kmax, beta=1):
fes = []
fes.append(gp.as_numpy_array(self.free_energy(x)))
for k in range(kmax):
x, _ = self.gibbs_sample(x, 1, beta=beta)
fes.append(gp.as_numpy_array(self.free_energy(x)))
fes=np.asarray(fes)
return fes
def dbn_save(ws_vh, ws_v, ws_h, path="./", file_prefix=""):
"""Temporary function for saving dbn weights from disk
"""
layer_count = len(ws_vh)
for i in range(layer_count):
np.save(path + file_prefix + "L" + repr(i + 1) + "_w_vh.npy", gnp.as_numpy_array(ws_vh[i]))
np.save(path + file_prefix + "L" + repr(i + 1) + "_w_v.npy", gnp.as_numpy_array(ws_v[i]))
np.save(path + file_prefix + "L" + repr(i + 1) + "_w_h.npy", gnp.as_numpy_array(ws_h[i]))
def generation_accuracy(label, ref_predict, myrbm,
tmpl_X, tmpl_Z, tmpl_ref_Z,
gen_X, gen_Z=None,
output_data_line=True, store_samples=True):
tmpl_Z = gp.as_numpy_array(tmpl_Z)
n_samples = gen_X.shape[0]
if n_samples < tmpl_X.shape[0]:
print "Warning: less generated samples than template samples were provided"
tmpl_X = tmpl_X[0:n_samples,:]
tmpl_Z = tmpl_Z[0:n_samples]
tmpl_ref_Z = tmpl_ref_Z[0:n_samples]
# calculate accuracy of reference classifier
diff = tmpl_Z - tmpl_ref_Z
errs = np.count_nonzero(diff)
corr = n_samples - errs
svc_acc = corr / n_samples
# classify generated data
if gen_Z is None:
gen_Z = ml.common.util.map(gp.as_numpy_array(gen_X), 100, ref_predict,
caption="Classifying results with reference predictor")
# count correctly classified samples
diff = tmpl_Z - gen_Z
errs = np.count_nonzero(diff)
corr = n_samples - errs
# find incorrect samples
incorrect_samples = np.nonzero(diff)[0]
guilty_samples = \
incorrect_samples[tmpl_ref_Z[incorrect_samples] ==
tmpl_Z[incorrect_samples]]
# calculate free energy
fes = ml.common.util.map(gen_X, 1000, myrbm.free_energy,
caption="Calculating free energy")
fes = gp.as_numpy_array(fes)
fe_mean = np.mean(fes)
fe_variance = ml.common.stats.unbiased_varince(fes)
# create stability object
s = Stability(label, n_samples, corr, svc_acc,
fe_mean, fe_variance, incorrect_samples, guilty_samples)
if store_samples:
s.tmpl_X = tmpl_X
s.tmpl_Z = tmpl_Z
s.tmpl_ref_Z = tmpl_ref_Z
s.gen_X = gen_X
s.gen_Z = gen_Z
# output performance data in table format
if output_data_line:
s.output_data_line()
return s
def or_rest_fast(z, x):
z = gp.as_numpy_array(z)
x = gp.as_numpy_array(x)
y = np.zeros(z.shape)
ym = np.ones(z.shape)
ym[(z == 1) & (x == 1)] = 0
y[(z == 1) & (x == 0)] = 1
return gp.as_garray(y), gp.as_garray(ym)
def save_parameters(rbm, epoch_or_filename):
if type(epoch_or_filename) == str:
filename = epoch_or_filename
else:
filename = "weights-%02i.npz" % epoch_or_filename
np.savez_compressed(
filename,
weights=gp.as_numpy_array(rbm.weights),
bias_vis=gp.as_numpy_array(rbm.bias_vis),
bias_hid=gp.as_numpy_array(rbm.bias_hid),
)
def nn_forward_pass(x, w, b, return_all=True):
"""
Forward pass for multilayer feed-forward sigmoid neural network
Hidden units have sigmoid non-linearity.
Output is soft-max.
x: DxN matrix of input data
w: Weights. List of weight matrices for each layer.
b: Biases. List of bias vectors for each layer
return_all: If True, returns hidden unit activations for each layer. If False
just returns the output layer activations
Returns a list h where each element is a matrix containing the activations
for that layer. h[0] is input data x.
"""
# ---- TEMP HACK --------------
# I should find a more seamless way of running in mixed (some operations
# with numpy, some with gnumpy) mode.
# I had to resort to this, because i needed the validation classification
# step in nn_train to run on CPU with numpy. GPU ran out of memory.
if isinstance(x, gnp.garray):
use_gpu = True
else:
use_gpu = False
layer_count = len(w)
if return_all:
hs = [x] # unit activations for each layer
h = x
# all layers except the output layer
for l in range(layer_count - 1):
if use_gpu:
a = gnp.dot(w[l].T, h) + b[l]
h = gnp.logistic(a)
else:
a = np.dot(gnp.as_numpy_array(w[l]).T, h) + gnp.as_numpy_array(b[l])
h = 1.0 / (1 + np.exp(-a))
if return_all:
hs.append(h)
# output layer
if use_gpu:
h = gnp.dot(w[-1].T, h) + b[-1]
h = gnp.exp(h) / gnp.sum(gnp.exp(h), axis=0) # soft-max
else:
h = np.dot(gnp.as_numpy_array(w[-1]).T, h) + gnp.as_numpy_array(b[-1])
h = np.exp(h) / np.sum(np.exp(h), axis=0) # soft-max
if return_all:
hs.append(h)
return hs
else:
return h
def generate_or_dataset(X, Z, samples):
X = gp.as_numpy_array(X)
Z = gp.as_numpy_array(Z)
si = np.random.randint(0, X.shape[0], size=(samples, 2))
x = X[si[:, 0], :]
y = X[si[:, 1], :]
O = or_sample(x, y)
OZ = np.zeros((samples, 2))
OZ[:, 0] = Z[si[:, 0]]
OZ[:, 1] = Z[si[:, 1]]
return O, OZ
def apply_nn_test(P, net, nCxt, outLayer, feat_dir, FeatList, outFeatDir, useDropout):
"Sends the test features for feedforward, and applies the PCA calculated from training files"
fdir = '';
inFeatList = open(feat_dir + FeatList).readlines()
for fname in inFeatList:
if fname == '\n':
continue
elif fname.rstrip()[-1] == ':':
fdir = fname.rstrip()[:-1]+'/'
print fdir
continue
elif fname.rstrip()[-3:]=='txt':
utt = np.loadtxt(feat_dir + fdir + fname[:-1])
# if not useDropout:
outputs = gpu.as_numpy_array(net.fprop_xf(utt, outLayer))
# else:
# outputs = gpu.as_numpy_array(net.fpropDropout(utt, outLayer))
assert(outputs.shape[1] == 40)
outputs = np.dot(outputs, P)
# if i/1*1 == i:
# gpu.free_reuse_cache()
outfile=htkmfc.HTKFeat_write(feat_dir + outFeatDir + 'test_feat/' + fdir[-9:] + fname[:-5], outputs.shape[1], htkmfc.USER)
outfile.writeall(outputs)
del outfile
del outputs
gpu.free_reuse_cache()
def forward(self, X):
self.X = X
# Num of examples
N = X.shape[0]
# Timespan
T = X.shape[1]
# Windows size
S = self.windowSize
# Channels
D = self.numChannels
# Num filters
F = self.numFilters
Z = np.zeros((N, T - S + 1, S, D), X.dtype)
for i in range(T - S + 1):
Z[:, i, :, :] = X[:, i:i + S, :]
Z = Z.reshape(N * (T - S + 1), S * D)
if self.gpu:
Z = gpu.as_garray(Z.astype('float32'))
Y = gpu.dot(Z, self.W)
Y = gpu.as_numpy_array(Y)
else:
Y = np.dot(Z, self.W)
Y = Y.reshape(N, T - S + 1, F)
self.Z = Z
return Y
def extract_patches(self, X, data_shape):
"""
Extract patches from input data according to its shape and the kernel
configurations.
Return patches matrix of size (H*W*N)x(C*ksize*ksize)
"""
X = gnp.as_numpy_array(X).reshape(-1, data_shape.c, data_shape.h,
data_shape.w)
out_shape = self.compute_output_shape(data_shape)
padded_h = (out_shape.h - 1) * self.stride + self.ksize
padded_w = (out_shape.w - 1) * self.stride + self.ksize
if padded_h > data_shape.h or padded_w > data_shape.w:
new_X = np.zeros((X.shape[0], X.shape[1], padded_h, padded_w),
dtype=X.dtype)
new_X[:, :, :data_shape.h, :data_shape.w] = X
X = new_X
assert data_shape.c == self.n_ic
patches = []
for i in xrange(0, X.shape[-2] - self.ksize + 1, self.stride):
for j in xrange(0, X.shape[-1] - self.ksize + 1, self.stride):
patches.append(X[:, :, i:i + self.ksize, j:j + self.ksize])
return np.concatenate(patches, axis=0).reshape(
-1, self.ksize * self.ksize * self.n_ic)
def recover_input(self, Y, out_shape, in_shape, **kwargs):
"""
Return recovered input and input_shape
"""
Y = gnp.as_numpy_array(Y).reshape(-1, out_shape.c, out_shape.h, out_shape.w).transpose((0,2,3,1)).reshape(-1, out_shape.c)
P = self.recover_patches_from_responses(Y, **kwargs)
return self.overlay_patches(P, out_shape, in_shape)
def extract_patches(self, X, data_shape):
"""
Extract patches from input data according to its shape and the kernel
configurations.
Return patches matrix of size (H*W*N)x(C*ksize*ksize)
"""
X = gnp.as_numpy_array(X).reshape(-1, data_shape.c, data_shape.h, data_shape.w)
out_shape = self.compute_output_shape(data_shape)
padded_h = (out_shape.h - 1) * self.stride + self.ksize
padded_w = (out_shape.w - 1) * self.stride + self.ksize
if padded_h > data_shape.h or padded_w > data_shape.w:
new_X = np.zeros((X.shape[0], X.shape[1], padded_h, padded_w), dtype=X.dtype)
new_X[:,:,:data_shape.h, :data_shape.w] = X
X = new_X
assert data_shape.c == self.n_ic
patches = []
for i in xrange(0, X.shape[-2] - self.ksize + 1, self.stride):
for j in xrange(0, X.shape[-1] - self.ksize + 1, self.stride):
patches.append(X[:,:,i:i+self.ksize, j:j+self.ksize])
return np.concatenate(patches, axis=0).reshape(-1, self.ksize*self.ksize*self.n_ic)
def get_random_patches(X, in_shape, ksize, n_patches_per_image, batch_size=100, pad_h=0, pad_w=0):
"""
Extract random patches from images X.
X: Nx(C*H*W) matrix, each row is an image
in_shape: shape information for each input image
ksize: size of the patches
n_patches_per_image: number of patches per image
batch_size: size of a batch. In each batch the patch locations will be the
same.
Return (n_patches_per_image*N)x(C*ksize*ksize) matrix, each row is one
patch.
"""
X = gnp.as_numpy_array(X).reshape(-1, in_shape.c, in_shape.h, in_shape.w)
if pad_h > 0 or pad_w > 0:
new_X = np.zeros((X.shape[0], in_shape.c, in_shape.h + pad_h, in_shape.w + pad_w), dtype=X.dtype)
new_X[:,:,:in_shape.h,:in_shape.w] = X
X = new_X
patches = []
for n in xrange(n_patches_per_image):
for im_idx in xrange(0, X.shape[0], batch_size):
h_start = np.random.randint(X.shape[-2] - ksize + 1)
w_start = np.random.randint(X.shape[-1] - ksize + 1)
patches.append(X[im_idx:im_idx+batch_size,:,h_start:h_start+ksize,w_start:w_start+ksize])
return np.concatenate(patches, axis=0).reshape(-1, in_shape.c*ksize*ksize)
def backward(self, dEdY):
N = dEdY.shape[0]
S = self.windowSize
T = dEdY.shape[1] + S - 1
F = dEdY.shape[2]
D = self.X.shape[2]
dEdY = dEdY.reshape(N * (T - S + 1), F)
dEdX = np.zeros(self.X.shape, self.X.dtype)
if self.gpu:
gdEdY = gpu.as_garray(dEdY.astype('float32'))
self.dEdW = gpu.dot(self.Z.transpose(), gdEdY)
else:
self.dEdW = np.dot(self.Z.transpose(), dEdY)
if self.outputdEdX:
if self.gpu:
gdEdZ = gpu.dot(gdEdY, self.W.transpose())
dEdZ = gpu.as_numpy_array(gdEdZ)
else:
dEdZ = np.dot(dEdY, self.W.transpose())
dEdZ = dEdZ.reshape(N, T - S + 1, S, D)
for t in range(0, T):
if t <= S - 1:
dEdX[:, t, :] = np.sum(dEdZ[:, range(0, t + 1), range(t, -1, -1), :], axis=1)
elif t >= T - S + 1:
dEdX[:, t, :] = np.sum(dEdZ[:, range(t - S + 1, T - S + 1), range(S - 1, S - (T - t) - 1, -1), :], axis=1)
else:
dEdX[:, t, :] = np.sum(dEdZ[:, range(t - S + 1, t + 1), range(S - 1, -1, -1), :], axis=1)
return dEdX
def forward(self, X):
self.X = X
# Num of examples
N = X.shape[0]
# Timespan
T = X.shape[1]
# Windows size
S = self.windowSize
# Channels
D = self.numChannels
# Num filters
F = self.numFilters
Z = np.zeros((N, T - S + 1, S, D), X.dtype)
for i in range(T - S + 1):
Z[:, i, :, :] = X[:, i : i + S, :]
Z = Z.reshape(N * (T - S + 1), S * D)
if self.gpu:
Z = gpu.as_garray(Z.astype('float32'))
Y = gpu.dot(Z, self.W)
Y = gpu.as_numpy_array(Y)
else:
Y = np.dot(Z, self.W)
Y = Y.reshape(N, T - S + 1, F)
self.Z = Z
return Y
def or_rest(z, x):
z = gp.as_numpy_array(z)
x = gp.as_numpy_array(x)
y = np.zeros(z.shape)
ym = np.ones(z.shape)
ym[(z == 1) & (x == 1)] = 0
y[(z == 1) & (x == 0)] = 1
# If pixels that are needed to explain the picture are forced on
# this results in pixels that cannot be turned off by the ml.rbm.
ym[(z == 1) & (x == 0)] = 0
# turn off whole force:
# ym = ym * 0
return gp.as_garray(y), gp.as_garray(ym)
def backprop(self, dLdY, return_on_gpu=False):
"""Perform backprop through this layer.
"""
# Backprop is just multiplication by the mask from feedforward
dLdX = gp.garray(dLdY) * self.dYdX
if not return_on_gpu:
dLdX = gp.as_numpy_array(dLdX).astype(np.float32)
return dLdX
def constrainMaxNorm(self):
if self.max_norm == -1:
return
for i in range(len(self.weights)):
wf = gnp.as_numpy_array(self.weights[i]).flatten()
if l2norm(wf) > self.max_norm:
wf = (wf/l2norm(wf)) * self.max_norm
self.weights[i] = gnp.garray(wf.reshape(self.weights[i].shape))
def check_performance(svc):
X, TX, y, Ty = ml.rbm.util.load_mnist(False)
X = gp.as_numpy_array(X)
y = gp.as_numpy_array(y)
TX = gp.as_numpy_array(TX)
Ty = gp.as_numpy_array(Ty)
print "Checking performance..."
nt = 10000
Py = svc.predict(X[0:nt])
training_err = ml.common.util.classification_error(Py, y[0:nt])
PTy = svc.predict(TX)
test_err = ml.common.util.classification_error(PTy, Ty)
print "Prediction error on first %d training samples: %g" % (nt, training_err)
print "Prediction error on test set: %g" % test_err
return svc
def train(self, x):
if self.prev:
x = self.prev.process(x)
x = gnp.as_garray(x)
self.avg = x.mean(axis=0)
cov = (x - self.avg).T.dot(x - self.avg) / x.shape[0]
cov = gnp.as_numpy_array(cov)
self.sqrcov = la.cholesky(cov + np.eye(cov.shape[0]) * 1e-5)
self.m = gnp.as_garray(la.inv(self.sqrcov + np.eye(x.shape[1]) * 1e-5))
def train(self, x):
if self.prev:
x = self.prev.process(x)
x = gnp.as_garray(x)
self.avg = x.mean(axis=0)
cov = (x - self.avg).T.dot(x - self.avg) / x.shape[0]
cov = gnp.as_numpy_array(cov)
self.sqrcov = la.cholesky(cov + np.eye(cov.shape[0]) * 1e-5)
self.m = gnp.as_garray(la.inv(self.sqrcov + np.eye(x.shape[1]) * 1e-5))
def generate_or_dataset_with_shift(S, SZ, ref_SZ, x_shift, y_shift, n_samples, sample_indices=None):
S = gp.as_numpy_array(S)
SZ = gp.as_numpy_array(SZ)
if sample_indices is not None:
si = sample_indices
else:
si = generate_sample_indices_for_or_dataset(S, n_samples)
X = S[si[:, 0]]
XZ = SZ[si[:, 0]]
ref_XZ = ref_SZ[si[:, 0]]
Y = S[si[:, 1]]
YZ = SZ[si[:, 1]]
ref_YZ = ref_SZ[si[:, 1]]
O = or_sample_with_shift(X, Y, x_shift, y_shift)
return X, XZ, ref_XZ, Y, YZ, ref_YZ, O
def recover_input(self, Y, out_shape, in_shape, **kwargs):
"""
Return recovered input and input_shape
"""
Y = gnp.as_numpy_array(Y).reshape(-1, out_shape.c, out_shape.h,
out_shape.w).transpose(
(0, 2, 3,
1)).reshape(-1, out_shape.c)
P = self.recover_patches_from_responses(Y, **kwargs)
return self.overlay_patches(P, out_shape, in_shape)
def or_rest(z, x):
z = gp.as_numpy_array(z)
x = gp.as_numpy_array(x)
y = np.zeros(z.shape)
ym = np.ones(z.shape)
ym[(z == 1) & (x == 1)] = 0
y[(z == 1) & (x == 0)] = 1
# "no on force":
# If pixels that are needed to explain the picture are forced on
# this results in pixels that cannot be turned off by the ml.rbm.
ym[(z == 1) & (x == 0)] = 0
# "no force":
#ym = ym * 0
# best is to have "no force" off and "no on force" on
return gp.as_garray(y), gp.as_garray(ym)
def train():
X, TX, y, Ty = ml.rbm.util.load_mnist(False)
X = gp.as_numpy_array(X)
y = gp.as_numpy_array(y)
TX = gp.as_numpy_array(TX)
Ty = gp.as_numpy_array(Ty)
#X = X[0:3000, ...]
#y = y[0:3000, ...]
print "Fitting SVM..."
svc = svm.SVC(kernel='rbf', verbose=True)
svc.fit(X, y)
filename = "mnist_svm.dat"
print "Writing model to %s" % filename
with gzip.open(filename, 'wb') as file:
pickle.dump(svc, file, pickle.HIGHEST_PROTOCOL)
return svc
def array(x, dtype=None, **kwargs):
if gnp.is_garray(x):
if dtype is gpu_float32:
return x
else:
return np.array(gnp.as_numpy_array(x), dtype=dtype, **kwargs)
else:
if dtype is gpu_float32:
return gnp.as_garray(np.array(x, **kwargs))
else:
return np.array(x, dtype=dtype, **kwargs)
def or_performance(myrbm, svc, OX, OZ, iters, gibbs_steps, beta):
OZ = gp.as_numpy_array(OZ)
batch_size = 1000
errs = 0
for i in range(int(math.ceil(OX.shape[0] / float(batch_size)))):
ox = OX[i*batch_size : (i+1)*batch_size, :]
oz = OZ[i*batch_size : (i+1)*batch_size, :]
x1, x2 = ml.rbm.orrbm.or_infer(myrbm, ox, iters, gibbs_steps, beta=beta)
y1 = svc.predict(gp.as_numpy_array(x1))
y2 = svc.predict(gp.as_numpy_array(x2))
z1 = oz[:, 0]
z2 = oz[:, 1]
diff = (z1 - y1)**2 + (z2 - y2)**2
errs += np.count_nonzero(diff)
err_prob = errs / float(OX.shape[0])
return err_prob
def train_model():
m = build_model()
stop = climin.stops.any_([
climin.stops.after_n_iterations(max_iter),
])
pause = climin.stops.modulo_n_iterations(n_report)
weight_decay = ((m.parameters.hidden_to_out ** 2).sum())
# + (m.parameters.hidden_to_hidden_0**2).sum()
# + (m.parameters.hidden_to_out**2).sum())
weight_decay /= m.exprs['inpt'].shape[0]
m.exprs['true_loss'] = m.exprs['loss']
m.exprs['loss'] = m.exprs['loss'] + c_wd * weight_decay
f_wd = m.function(['inpt'], c_wd * weight_decay)
n_wrong = 1 - T.eq(T.argmax(m.exprs['output'], axis=1), T.argmax(m.exprs['target'], axis=1)).mean()
f_n_wrong = m.function(['inpt', 'target'], n_wrong)
losses = []
v_losses = []
print 'max iter', max_iter
start = time.time()
# Set up a nice printout.
keys = '#', 'loss', 'val loss', 'seconds', 'wd', 'train emp', 'test emp'
max_len = max(len(i) for i in keys)
header = '\t'.join(i for i in keys)
print header
print '-' * len(header)
f_loss = m.function(['inpt', 'target'], ['true_loss', 'loss'])
for i, info in enumerate(m.powerfit((X, Z), (TX, TZ), stop, pause)):
if info['n_iter'] % n_report != 0:
continue
passed = time.time() - start
losses.append(info['loss'])
v_losses.append(info['val_loss'])
#img = tile_raster_images(fe.parameters['in_to_hidden'].T, image_dims, feature_dims, (1, 1))
#save_and_display(img, 'filters-%i.png' % i)
info.update({
'time': passed,
'l2-loss': scalar(f_wd(X)),
'train_emp': scalar(f_n_wrong(X, Z)),
'test_emp': scalar(f_n_wrong(TX, TZ)),
})
row = '%(n_iter)i\t%(loss)g\t%(val_loss)g\t%(time)g\t%(l2-loss)g\t%(train_emp)g\t%(test_emp)g' % info
print row
np.savez_compressed(savepath, parameters=gp.as_numpy_array(m.parameters.data[...]))
def mixing_quality(samples):
samples = gp.as_numpy_array(samples)
n_steps = samples.shape[0]
avg_dists = []
for step in range(n_steps-1):
v_now = samples[step, :, :]
v_next = samples[step+1, :, :]
dists = np.sqrt(np.sum(np.power(v_next - v_now, 2), axis=1))
avg_dists.append(np.mean(dists))
return np.mean(avg_dists)
def gradDebug(self, inputBatch, targetBatch):
inputBatch = inputBatch if isinstance(inputBatch, gnp.garray) else gnp.garray(inputBatch)
targetBatch = targetBatch if isinstance(targetBatch, gnp.garray) else gnp.garray(targetBatch)
mbsz = inputBatch.shape[0]
outputActs = self.fprop(inputBatch)
outputErrSignal = -self.outputActFunct.dErrordNetInput(targetBatch, self.state[-1], outputActs)
errSignals = self.bprop(outputErrSignal)
for i, (WGrad, biasGrad) in enumerate(self.gradients(self.state, errSignals)):
self.WGrads[i] = WGrad
self.biasGrads[i] = biasGrad
allWeightGrads = itertools.chain(self.WGrads, self.biasGrads)
return gnp.as_numpy_array(gnp.concatenate([dw.ravel() for dw in allWeightGrads]))
def gradDebug(self, inputBatch, targetBatch):
inputBatch = inputBatch if isinstance(inputBatch, gnp.garray) else gnp.garray(inputBatch)
targetBatch = targetBatch if isinstance(targetBatch, gnp.garray) else gnp.garray(targetBatch)
mbsz = inputBatch.shape[0]
outputActs = self.fprop(inputBatch)
outputErrSignal = -self.outputActFunct.dErrordNetInput(targetBatch, self.state[-1], outputActs)
# error = self.outputActFunct.error(targetBatch, self.state[-1], outputActs)
errSignals = self.bprop(outputErrSignal)
for i, (WGrad, biasGrad) in enumerate(self.gradients(self.state, errSignals)):
# update the weight increments
self.WGrads[i] = WGrad
self.biasGrads[i] = biasGrad
allWeightGrads = itertools.chain(self.WGrads, self.biasGrads)
return gnp.as_numpy_array(gnp.concatenate([dw.ravel() for dw in allWeightGrads]))
def backward(self, dEdY):
dEdZ = self.activeFn.backward(dEdY, self.Y, 0)
if self.gpu:
gdEdZ = gpu.as_garray(dEdZ.astype('float32'))
self.dEdW = gpu.dot(self.X.transpose(), gdEdZ)
if self.bias:
dEdX = gpu.dot(gdEdZ, self.W[:-1, :].transpose())
else:
dEdX = gpu.dot(gdEdZ, self.W.transpose())
dEdX = gpu.as_numpy_array(dEdX)
else:
self.dEdW = np.dot(self.X.transpose(), dEdZ)
if self.bias:
dEdX = np.dot(dEdZ, self.W[:-1, :].transpose())
else:
dEdX = np.dot(dEdZ, self.W.transpose())
return dEdX if self.outputdEdX else None
def write(self, dat):
"""
add dat to buffer
"""
dat=gp.as_numpy_array(dat)
end=self.index+dat.shape[0]
if end<=self.maxrows:
if self.data==None:
self.data=np.empty((self.maxrows, dat.shape[1]))
self.data[self.index:end]=dat
self.index=end
elif self.index==self.maxrows:
self.flush()
self.index=0
self.write(dat)
else:
raise Exception("disk write buffer is not algined with batchsize")
def write(self, dat):
"""
add dat to buffer
"""
dat = gp.as_numpy_array(dat)
end = self.index + dat.shape[0]
if end <= self.maxrows:
if self.data == None:
self.data = np.empty((self.maxrows, dat.shape[1]))
self.data[self.index:end] = dat
self.index = end
elif self.index == self.maxrows:
self.flush()
self.index = 0
self.write(dat)
else:
raise Exception("disk write buffer is not algined with batchsize")
def backward(self, dEdY):
N = dEdY.shape[0]
S = self.windowSize
T = dEdY.shape[1] + S - 1
F = dEdY.shape[2]
D = self.X.shape[2]
dEdY = dEdY.reshape(N * (T - S + 1), F)
dEdX = np.zeros(self.X.shape, self.X.dtype)
if self.gpu:
gdEdY = gpu.as_garray(dEdY.astype('float32'))
self.dEdW = gpu.dot(self.Z.transpose(), gdEdY)
else:
self.dEdW = np.dot(self.Z.transpose(), dEdY)
if self.outputdEdX:
if self.gpu:
gdEdZ = gpu.dot(gdEdY, self.W.transpose())
dEdZ = gpu.as_numpy_array(gdEdZ)
else:
dEdZ = np.dot(dEdY, self.W.transpose())
dEdZ = dEdZ.reshape(N, T - S + 1, S, D)
for t in range(0, T):
if t <= S - 1:
dEdX[:, t, :] = np.sum(dEdZ[:,
range(0, t + 1),
range(t, -1, -1), :],
axis=1)
elif t >= T - S + 1:
dEdX[:, t, :] = np.sum(dEdZ[:,
range(t - S + 1, T - S + 1),
range(S - 1, S - (T - t) -
1, -1), :],
axis=1)
else:
dEdX[:, t, :] = np.sum(dEdZ[:,
range(t - S + 1, t + 1),
range(S - 1, -1, -1), :],
axis=1)
return dEdX
def apply_nn_train_prePCA(net, nCxt, outLayer, feat_dir, FeatList, outFeatDir, Nframes, useDropout):
"""Sends the training features for feedforward and collects the output in a matrix X for performing PCA"""
fdir = '';
dim = net.weights[-2].shape[1]
X = np.zeros((Nframes,dim))
inFeatList = open(feat_dir + FeatList).readlines()
fro = 0;
to = 0;
for fname in inFeatList:
if fname.rstrip()[-1] == ':':
fdir = fname.rstrip()[:-1]+'/'
continue
elif fname.rstrip()[-3:]=='txt':
utt = np.loadtxt(feat_dir + fdir + fname.rstrip())
# if not useDropout:
outputs = gpu.as_numpy_array(net.fprop_xf(utt, outLayer))
# else:
# outputs = gpu.as_numpy_array(net.fpropDropout(utt, outLayer))
assert(outputs.shape[1] == 40)
fro = to
to = fro + outputs.shape[0]
# if X == None:
# X = outputs
# else:
X[fro:to] = outputs
# X = np.concatenate((X,outputs))
# if i/1*1 == i:
# gpu.free_reuse_cache()
# np.savetxt(feat_dir + outFeatDir + 'train_16k_prePCA/' + fname, gpu.as_numpy_array(outputs))
np.save(feat_dir + outFeatDir + 'train_prePCA/' + fname[:-5], outputs)
del outputs
gpu.free_reuse_cache()
#End of for
return X
def get_random_patches(X,
in_shape,
ksize,
n_patches_per_image,
batch_size=100,
pad_h=0,
pad_w=0):
"""
Extract random patches from images X.
X: Nx(C*H*W) matrix, each row is an image
in_shape: shape information for each input image
ksize: size of the patches
n_patches_per_image: number of patches per image
batch_size: size of a batch. In each batch the patch locations will be the
same.
Return (n_patches_per_image*N)x(C*ksize*ksize) matrix, each row is one
patch.
"""
X = gnp.as_numpy_array(X).reshape(-1, in_shape.c, in_shape.h, in_shape.w)
if pad_h > 0 or pad_w > 0:
new_X = np.zeros(
(X.shape[0], in_shape.c, in_shape.h + pad_h, in_shape.w + pad_w),
dtype=X.dtype)
new_X[:, :, :in_shape.h, :in_shape.w] = X
X = new_X
patches = []
for n in xrange(n_patches_per_image):
for im_idx in xrange(0, X.shape[0], batch_size):
h_start = np.random.randint(X.shape[-2] - ksize + 1)
w_start = np.random.randint(X.shape[-1] - ksize + 1)
patches.append(X[im_idx:im_idx + batch_size, :,
h_start:h_start + ksize, w_start:w_start + ksize])
return np.concatenate(patches, axis=0).reshape(-1,
in_shape.c * ksize * ksize)
def costAndGrad(self, data, labels):
# forward prop
self.hActs[0] = data
i = 1
for w, b in self.stack:
self.hActs[i] = w.dot(self.hActs[i - 1]) + b
if i <= len(self.layerSizes):
self.hActs[i] = self.activation(self.hActs[i])
i += 1
probs = self.hActs[-1] - gp.max(self.hActs[-1], axis=0)
probs = gp.exp(probs)
probs = probs / gp.sum(probs, axis=0)
labelMat = np.zeros(probs.shape)
labelMat[labels, range(self.mbSize)] = 1
labelMat = gp.garray(labelMat)
cost = -(1. / self.mbSize) * np.nansum(
gp.as_numpy_array(labelMat * gp.log(probs)))
if not self.train:
return cost, None
# back prop
self.deltas[-1] = probs - labelMat
i = len(self.layerSizes) - 1
for w, b in reversed(self.stack[1:]):
grad = self.activation(self.hActs[i + 1], True)
self.deltas[i] = w.T.dot(self.deltas[i + 1]) * grad
i -= 1
# compute gradients
for i in range(len(self.grad)):
self.grad[i][0] = (1. / self.mbSize) * self.deltas[i].dot(
self.hActs[i].T)
self.grad[i][1] = (1. / self.mbSize) * gp.sum(
self.deltas[i], axis=1).reshape(-1, 1)
return cost, self.grad
def getWeights(self):
if self.gpu:
return gpu.as_numpy_array(self.W)
else:
return self.W
def costAndGrad(self, data, labels, key=None):
"""
Forward prop entire utterance
Call CTC cost function
Compute gradient
data is a 2-D matrix where each column is a single time frame
Number of input frames changes across iterations
labels is a vector of symbol ids, length unknown and does not
depend on the number of time frames
"""
## forward prop
T = data.shape[1]
sizes = [self.inputDim] + self.layerSizes + [self.outputDim]
stackMax = len(self.stack) - 1
if self.temporalLayer > 0:
stackMax -= 1
self.hActs = [gp.empty((s, T)) for s in sizes]
self.hActs[0] = data
#for t in range(T):
i = 1
for l in range(stackMax + 1):
w, b = self.stack[l]
self.hActs[i] = w.dot(self.hActs[i - 1]) + b
# loop over time for recurrent layer
if (self.temporalLayer - 1) == l:
for t in range(T):
if t > 0:
self.hActs[i][:, t] += self.stack[-1][0].dot(
self.hActs[i][:, t - 1])
# nonlinearity
if i <= stackMax:
self.hActs[i][:, t] = self.activation(self.hActs[i][:,
t])
# hidden layer activation function for batch forward prop
elif i <= stackMax:
self.hActs[i] = self.activation(self.hActs[i])
# w_t,b_t = self.stack[-1][0]
# self.hActs[i][:,t] += self.stack[-1][0].dot(self.hActs[i][:,t-1])
i += 1
# convert final layer to probs after all time iteration complete
probs = self.hActs[-1] - gp.max(self.hActs[-1], axis=0)
probs = gp.as_numpy_array(probs)
probs = np.exp(probs)
probs = probs / np.sum(probs, axis=0)
## pass probs and label string to ctc loss
# TODO how much does passing to different function cost us?
cost, delta_output, skip = ctc.ctc_loss(probs,
labels.squeeze(),
blank=0)
# Store probabilities and error signal for a given key
if key is not None and key in self.hist:
self.hist[key].append((probs, delta_output))
if not self.train:
return cost, None
delta_output = gp.garray(delta_output)
## back prop through time
# zero gradients
self.grad = [[gp.zeros(w.shape), gp.zeros(b.shape)]
for w, b in self.stack]
if self.temporalLayer > 0:
delta_t = np.zeros(self.layerSizes[self.temporalLayer - 1])
for t in reversed(range(T)):
# get delta from loss function
delta = delta_output[:, t].T
# compute gradient for output layer
#print self.hActs[-2].shape, delta.shape, self.stack[stackMax][0].shape
#print delta.reshape(-1,1).shape, self.hActs[-2][:,t].reshape(-1,1).shape
# TODO can we get rid of some of these annoying reshape -1 1?
self.grad[stackMax][0] += delta.reshape(-1, 1).dot(
self.hActs[-2][:, t].reshape(-1, 1).T)
self.grad[stackMax][1] += delta.reshape(-1, 1)
# push delta through output layer
delta = self.stack[stackMax][0].T.dot(delta)
# iterate over lower layers
i = len(self.layerSizes) - 1
while i >= 0:
# add the temporal delta if this is the recurrent layer
if (self.temporalLayer - 1) == i:
#print delta.shape, delta_t.shape
delta += delta_t
# push delta through activation function for this layer
#print i, stackMax, delta.shape, self.hActs[i+1][:,t].shape
delta = delta * self.activation(self.hActs[i + 1][:, t], True)
#embed()
# compute the gradient
#print i, delta.shape, self.hActs[i][:,t].T.reshape(1,-1).shape, self.grad[i][0].shape
self.grad[i][0] += delta.reshape(-1, 1).dot(
self.hActs[i][:, t].T.reshape(1, -1))
self.grad[i][1] += delta.reshape(-1, 1)
# add the temporal delta if this is the recurrent layer
if (self.temporalLayer - 1) == i and t > 0:
self.grad[-1][0] += delta.reshape(-1, 1).dot(
self.hActs[i + 1][:, t - 1].T.reshape(1, -1))
# push delta through temporal connections
delta_t = self.stack[-1][0].T.dot(delta)
# HACK no bias for temporal layer. Give it a gradient of 0
self.grad[-1][1] = np.zeros((2, 1))
# push the delta downward
w, b = self.stack[i]
delta = w.T.dot(delta)
i -= 1
#print self.grad
return cost, self.grad, skip
def decode(self, z, in_shape, **kwargs):
r = gnp.as_numpy_array(self.ae.decoder.forward_prop(z))
out_shape = self.convnet.compute_output_shape(in_shape)
assert out_shape.size() == r.shape[1]
return self.convnet.recover_input(r, in_shape, **kwargs)
def gather(x):
"""Copys array from GPU if running on GPU"""
if GPU:
return gnumpy.as_numpy_array(x)
else:
return x
def costAndGrad(self,data,labels=None,key=None):
"""
Forward prop entire utterance
Call CTC cost function
Compute gradient
data is a 2-D matrix where each column is a single time frame
Number of input frames changes across iterations
labels is a vector of symbol ids, length unknown and does not
depend on the number of time frames
"""
## forward prop
# this is the same as minibatch forward prop
# since we pre-compute context window features for each time
self.hActs[0] = data
i = 1
for w,b in self.stack:
self.hActs[i] = w.dot(self.hActs[i-1])+b
if i <= len(self.layerSizes):
self.hActs[i] = self.activation(self.hActs[i])
i += 1
probs = self.hActs[-1]-gp.max(self.hActs[-1],axis=0)
probs = gp.as_numpy_array(probs)
probs = np.exp(probs)
probs = probs/np.sum(probs,axis=0)
# probs[probs<1e-12] = 1e-12 # TODO have to clamp?
## pass probs and label string to ctc loss
# TODO how much does passing to different function cost us?
if not self.train:
return ctc.decode_best_path(probs, ref=labels, blank=0)
#return ctc.decode_bp_bigrams(probs, blank=0, B=None)
cost, self.deltas[-1], skip = ctc.ctc_loss(probs, labels, blank=0)
# Bad utterance ?
if skip:
return cost,self.grad,skip
# Store probabilities and error signal for a given key
#if key is not None and key in self.hist:
# self.hist[key].append((probs,self.deltas[-1]))
self.deltas[-1] = gp.garray(self.deltas[-1])
# back prop
i = len(self.layerSizes)-1
for w,b in reversed(self.stack[1:]):
grad = self.activation(self.hActs[i+1], True)
self.deltas[i] = w.T.dot(self.deltas[i+1])*grad
i -= 1
# compute gradients
# NOTE we do not divide by utterance length.
# Will need to scale up weight norm penalty accordingly
for i in range(len(self.grad)):
self.grad[i][0] = self.deltas[i].dot(self.hActs[i].T)
self.grad[i][1] = gp.sum(self.deltas[i],axis=1).reshape(-1,1)
return cost,self.grad,skip