def param_init_encoder(options, params, prefix='lstm_encoder'):
n_x = options['n_x']
n_h = options['n_h']
W = np.concatenate([uniform_weight(n_x,n_h),
uniform_weight(n_x,n_h),
uniform_weight(n_x,n_h),
uniform_weight(n_x,n_h)], axis=1)
params[_p(prefix, 'W')] = W
U = np.concatenate([ortho_weight(n_h),
ortho_weight(n_h),
ortho_weight(n_h),
ortho_weight(n_h)], axis=1)
params[_p(prefix, 'U')] = U
params[_p(prefix,'b')] = zero_bias(4*n_h)
# It is observed that setting a high initial forget gate bias for LSTMs can
# give slighly better results (Le et al., 2015). Hence, the initial forget
# gate bias is set to 3.
params[_p(prefix, 'b')][n_h:2*n_h] = 3*np.ones((n_h,)).astype(theano.config.floatX)
return params
def gru_layer(tparams, state_below, init_state, options, prefix='gru', mask=None, **kwargs):
"""
Feedforward pass through GRU
"""
nsteps = state_below.shape[0]
if state_below.ndim == 3:
n_samples = state_below.shape[1]
else:
n_samples = 1
dim = tparams[_p(prefix,'Ux')].shape[1]
if init_state == None:
init_state = tensor.alloc(0., n_samples, dim)
if mask == None:
mask = tensor.alloc(1., state_below.shape[0], 1)
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n*dim:(n+1)*dim]
return _x[:, n*dim:(n+1)*dim]
state_below_ = tensor.dot(state_below, tparams[_p(prefix, 'W')]) + tparams[_p(prefix, 'b')]
state_belowx = tensor.dot(state_below, tparams[_p(prefix, 'Wx')]) + tparams[_p(prefix, 'bx')]
U = tparams[_p(prefix, 'U')]
Ux = tparams[_p(prefix, 'Ux')]
def _step_slice(m_, x_, xx_, h_, U, Ux):
preact = tensor.dot(h_, U)
preact += x_
r = tensor.nnet.sigmoid(_slice(preact, 0, dim))
u = tensor.nnet.sigmoid(_slice(preact, 1, dim))
preactx = tensor.dot(h_, Ux)
preactx = preactx * r
preactx = preactx + xx_
h = tensor.tanh(preactx)
h = u * h_ + (1. - u) * h
h = m_[:,None] * h + (1. - m_)[:,None] * h_
return h
seqs = [mask, state_below_, state_belowx]
_step = _step_slice
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info = [init_state],
non_sequences = [tparams[_p(prefix, 'U')],
tparams[_p(prefix, 'Ux')]],
name=_p(prefix, '_layers'),
n_steps=nsteps,
profile=False,
strict=True)
rval = [rval]
return rval
def param_init_fflayer(options, params, prefix='ff', nin=None, nout=None,
ortho=True):
if nin is None:
nin = options['dim_proj']
if nout is None:
nout = options['dim_proj']
params[_p(prefix, 'W')] = norm_weight(nin, nout, scale=0.01, ortho=ortho)
params[_p(prefix, 'b')] = np.zeros((nout,)).astype('float32')
return params
def fflayer(tparams,
state_below,
options,
prefix='rconv',
activ='lambda x: tensor.tanh(x)',
**kwargs):
"""
Feedforward pass
"""
return eval(activ)(tensor.dot(state_below, tparams[_p(prefix, 'W')]) +
tparams[_p(prefix, 'b')])
def batch_norm(tparams, input, options, prefix='cnn'):
""" layer1_input: n_sample * n_feature 64*20
input_shape: (num of hiddens, number of input features) 200*20
pred_shape: (num of labels, number of hiddens) 2*200
y_recon : n_label *n_sample 2*64
"""
input_hat = (input - input.mean(0)) / (input.std(0) + 1.0 / options['L'])
input_ = input_hat * tparams[_p(prefix, 'gamma')] + tparams[_p(
prefix, 'beta')]
return input_
def encoder(tparams, state_below, mask, seq_output=False, prefix='lstm_encoder'):
""" state_below: size of n_steps * n_samples * n_x
"""
n_steps = state_below.shape[0]
n_samples = state_below.shape[1]
n_h = tparams[_p(prefix,'U')].shape[0]
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n*dim:(n+1)*dim]
return _x[:, n*dim:(n+1)*dim]
state_below_ = tensor.dot(state_below, tparams[_p(prefix, 'W')]) + \
tparams[_p(prefix, 'b')]
def _step(m_, x_, h_, c_, U):
preact = tensor.dot(h_, U)
preact += x_
i = tensor.nnet.sigmoid(_slice(preact, 0, n_h))
f = tensor.nnet.sigmoid(_slice(preact, 1, n_h))
o = tensor.nnet.sigmoid(_slice(preact, 2, n_h))
c = tensor.tanh(_slice(preact, 3, n_h))
c = f * c_ + i * c
c = m_[:, None] * c + (1. - m_)[:, None] * c_
h = o * tensor.tanh(c)
h = m_[:, None] * h + (1. - m_)[:, None] * h_
return h, c
seqs = [mask, state_below_]
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info=[tensor.alloc(numpy_floatX(0.),
n_samples,n_h),
tensor.alloc(numpy_floatX(0.),
n_samples,n_h)],
non_sequences = [tparams[_p(prefix, 'U')]],
name=_p(prefix, '_layers'),
n_steps=n_steps,
strict=True)
h_rval = rval[0]
if seq_output:
return h_rval
else:
# size of n_samples * n_h
return h_rval[-1]
def _init_params(self):
shape_io = (self.n_in, self.n_out)
if self.orth:
if self.n_in != self.n_out :
raise ValueError('n_in != n_out when require orth in FeedForward')
self.W = ortho_weight(rng=self.rng, shape=shape_io, name=_p(self.pname, 'W'))
else:
self.W = norm_weight(rng=self.rng, shape=shape_io, name=_p(self.pname, 'W'))
self.b = constant_weight(shape=(self.n_out, ), name=_p(self.pname, 'b'))
self.params = [self.W, self.b]
def mlp_layer_linear(tparams, layer1_input, prefix='mlp_layer'):
""" layer1_input: n_sample * n_feature 64*20
input_shape: (num of hiddens, number of input features) 200*20
pred_shape: (num of labels, number of hiddens) 2*200
y_recon : n_label *n_sample 2*64
"""
hidden_2_out = tensor.nnet.sigmoid(tensor.dot(layer1_input, tparams[_p(prefix,'W1')].T) + tparams[_p(prefix,'b1')] ) # 64*200
y_recons = tensor.dot(hidden_2_out, tparams[_p(prefix,'V1')].T) + tparams[_p(prefix,'c1')]
#y_recons = tensor.tanh(y_recons) * 10 # avoid numerical issues/label smoothing
#y_recons = tensor.nnet.softmax(y_recons) # 64*2
return y_recons
def param_init_fflayer(options, params, prefix='ff', nin=None, nout=None, ortho=True):
"""
Affine transformation + point-wise nonlinearity
"""
if nin == None:
nin = options['dim_proj']
if nout == None:
nout = options['dim_proj']
params[_p(prefix,'W')] = norm_weight(nin, nout, ortho=ortho)
params[_p(prefix,'b')] = numpy.zeros((nout,)).astype('float32')
return params
def param_init_fflayer(options, params, prefix='ff', nin=None, nout=None, ortho=True):
"""
Affine transformation + point-wise nonlinearity
"""
if nin == None:
nin = options['dim_proj']
if nout == None:
nout = options['dim_proj']
params[_p(prefix,'W')] = xavier_weight(nin, nout)
params[_p(prefix,'b')] = numpy.zeros((nout,)).astype('float32')
return params
def decoder_layer(tparams, state_below, prefix='decoder_lstm'):
""" state_below: size of n_steps * n_samples * n_x
"""
nsteps = state_below.shape[0]
n_h = tparams[_p(prefix, 'U')].shape[0]
if state_below.ndim == 3:
n_samples = state_below.shape[1]
else:
n_samples = 1
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n * dim:(n + 1) * dim]
return _x[:, n * dim:(n + 1) * dim]
def _step(x_, h_, c_, U):
preact = tensor.dot(h_, U)
preact += x_
i = tensor.nnet.sigmoid(_slice(preact, 0, n_h))
f = tensor.nnet.sigmoid(_slice(preact, 1, n_h))
o = tensor.nnet.sigmoid(_slice(preact, 2, n_h))
c = tensor.tanh(_slice(preact, 3, n_h))
c = f * c_ + i * c
h = o * tensor.tanh(c)
return h, c
state_below_ = tensor.dot(state_below, tparams[_p(
prefix, 'W')]) + tparams[_p(prefix, 'b')]
seqs = [state_below_]
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info=[
tensor.alloc(numpy_floatX(0.), n_samples,
n_h),
tensor.alloc(numpy_floatX(0.), n_samples,
n_h)
],
non_sequences=[tparams[_p(prefix, 'U')]],
name=_p(prefix, '_layers'),
n_steps=nsteps,
strict=True)
h_rval = rval[0]
return h_rval
def param_init_batch_norm(input_shape, params, prefix='cnn'):
""" input_shape: (num of hiddens, number of input features)
pred_shape: (num of labels, number of hiddens)
"""
beta = np.ones((input_shape[1], ), dtype=theano.config.floatX) * 0.01
gamma = np.ones((input_shape[1], ), dtype=theano.config.floatX) * 0.1
params[_p(prefix, 'beta')] = beta
params[_p(prefix, 'gamma')] = gamma
return params
def _init_params(self):
shape_xh = (self.n_in * 3, self.n_hids)
shape_hh = (self.n_hids * 3, self.n_hids)
self.W_x = norm_weight(shape=shape_xh, name=_p(self.pname, 'W_x'))
self.b = constant_weight(shape=(self.n_hids * 3, ),
name=_p(self.pname, 'b'))
self.W_h = ortho_weight(shape=shape_hh, name=_p(self.pname, 'W_h'))
self.params = [self.W_x, self.W_h, self.b]
self.GRU_op = mkl_gru.GRU(hid=self.n_hids,
return_sequences=True,
max_len=self.max_len)
self.h_init_state = numpy.zeros((80, 1000), numpy.float64)
def param_init_fflayer(self,
options,
params,
prefix='ff',
nin=None,
nout=None):
if nin == None:
nin = options['dim_proj']
if nout == None:
nout = options['dim_proj']
params[_p(prefix, 'W')] = norm_weight(nin, nout, scale=0.01)
params[_p(prefix, 'b')] = numpy.zeros((nout, )).astype('float32')
return params
def _init_params(self):
shape_io = (self.n_in_0, self.n_out)
if self.orth:
if self.n_in_0 != self.n_out:
raise ValueError('n_in != n_out when require orth in FeedForward')
self.W = ortho_weight(rng=self.rng, shape=shape_io, name=_p(self.pname, 'W'))
else:
self.W = norm_weight(rng=self.rng, shape=shape_io, name=_p(self.pname, 'W'))
self.params = [self.W]
self.ff = FeedForward(self.n_in_1, self.n_out, orth=self.orth, rng=self.rng, name=_p(self.pname, 'FF_W') )
self.params.extend(self.ff.params)
def param_init_encoder(filter_shape, params, prefix='cnn_encoder'):
""" filter_shape: (number of filters, num input feature maps, filter height,
filter width)
image_shape: (batch_size, num input feature maps, image height, image width)
"""
W = np.asarray(rng.uniform(low=-0.01,high=0.01,size=filter_shape),dtype=theano.config.floatX)
b = np.zeros((filter_shape[0],), dtype=theano.config.floatX)
params[_p(prefix,'W')] = W
params[_p(prefix,'b')] = b
return params
def param_init_encoder(filter_shape, params, prefix='cnn_encoder'):
""" filter_shape: (number of filters, num input feature maps, filter height,
filter width)
image_shape: (batch_size, num input feature maps, image height, image width)
"""
W = np.asarray(rng.uniform(low=-0.01,high=0.01,size=filter_shape),dtype=theano.config.floatX)
b = np.zeros((filter_shape[0],), dtype=theano.config.floatX)
params[_p(prefix,'W')] = W
params[_p(prefix,'b')] = b
return params
def apply_pyramid(self, state_below, mask_below=None, init_state=None, context=None):
'''
state_below: shape=[seq_len, batch, n_in]
init_state: shape=[batch, seq_len, hid]
'''
n_steps = state_below.shape[0]
if state_below.ndim == 3:
batch_size = state_below.shape[1]
else:
batch_size = 1
state_below = state_below.reshape((n_steps, batch_size, state_below.shape[1]))
if mask_below is None:
mask_below = T.alloc(numpy.float32(1.), n_steps, 1)
if self.with_context:
assert context
if init_state is None:
init_state = T.tanh(T.dot(context, self.W_c_init))
c_z = T.dot(context, self.W_cz)
c_r = T.dot(context, self.W_cr)
c_h = T.dot(context, self.W_ch)
non_sequences = [c_z, c_r, c_h]
rval, updates = theano.scan(self._step_context,
sequences=[state_below, mask_below],
non_sequences=non_sequences,
outputs_info=[init_state],
name=_p(self.pname, 'layers'),
n_steps=n_steps)
else:
if init_state is None:
init_state = T.alloc(numpy.float32(0.), batch_size, n_steps, self.n_hids)
state_below_xh = T.dot(state_below, self.W_xh) + self.b_h
state_below_xzr = T.dot(state_below, self.W_xzr) + self.b_zr
step_idx = T.arange(n_steps)
sequences = [state_below_xh, state_below_xzr, mask_below, step_idx]
outputs_info=[init_state]
non_sequences = []
rval, updates = theano.scan(self._pyramid_step,
sequences=sequences,
outputs_info=outputs_info,
non_sequences=non_sequences,
name=_p(self.pname, 'layers'),
n_steps=n_steps)
self.output = rval
return self.output
def param_init_decoder(options, params, prefix='decoder_vanilla'):
n_x = options['n_x']
n_h = options['n_h']
W = uniform_weight(n_x, n_h)
params[_p(prefix, 'W')] = W
U = ortho_weight(n_h)
params[_p(prefix, 'U')] = U
params[_p(prefix, 'b')] = zero_bias(n_h)
return params
def param_init_action_response_layer(options, params, constraints, prefix='ar',
nin=0, rng=None, unif_range=0.2,
level=0, **kwargs):
'''
Action response layers.
'''
rng = init_rng(rng)
n_features = options['hidden_units'][-1]
if options['shared_ld']:
params, constraints = init_level_dist(params, unif_range, nin, rng, constraints)
else:
if level > 0:
params[_p(prefix, 'ld')] = floatx(rng.uniform(size=(level),
low=0.1,
high=0.9))
params[_p(prefix, 'ld')] /= params[_p(prefix, 'ld')].sum()
constraints['simplex'] = constraints.get('simplex', []) + [_p(prefix, 'ld')]
initial_Wf = numpy.zeros(n_features)
initial_Wf += floatx(rng.uniform(size=(n_features), low=0., high=unif_range))
initial_Wf /= initial_Wf.sum()
if level == 0:
params[_p(prefix, 'Wf')] = floatx(initial_Wf)
constraints['simplex'] = constraints.get('simplex', []) + [_p(prefix, 'Wf')]
if level > 0:
params[_p(prefix, 'W_h')] = floatx(rng.uniform(size=(1+options['hidden_units'][-1]),
low=-0.01,
high=0.01))
if level > 0:
params[_p(prefix, 'lam')] = floatx(1.0)
return params, constraints
def deconv_depool2(layer0_input, tparams, options, prefix):
if prefix == 'd':
depool_out = depool_repeat(layer0_input, options['e_pool_size'])
elif prefix == 'd2':
depool_out = depool_repeat(layer0_input, options['e2_pool_size'])
s = int(np.floor(options[_p(prefix, 'Nt')] / 2.))
h = int((2 * options[_p(prefix, 'K')] - 2) / 2.)
deconv_out = conv.conv2d(input=depool_out.dimshuffle(0, 'x', 1, 2),
filters=tparams[_p(prefix, 'W')],
filter_shape=options[_p(prefix, 'filter_shape')],
border_mode='full')[:, :, h, s - 1:-s]
doutput = (deconv_out +
tparams[_p(prefix, 'bias')].dimshuffle('x', 0, 'x')
) #.reshape((deconv_out.shape[0],options['C'],options['T']))
return doutput
def param_init_lstm(self, params, nin, dim, prefix='lstm'):
assert prefix is not None
# Stack the weight matricies for faster dot prods
W = np.concatenate([norm_weight(nin, dim),
norm_weight(nin, dim),
norm_weight(nin, dim),
norm_weight(nin, dim)], axis=1)
params[_p(prefix, 'W')] = W # to_lstm_W:(512,2048)
U = np.concatenate([ortho_weight(dim),
ortho_weight(dim),
ortho_weight(dim),
ortho_weight(dim)], axis=1)
params[_p(prefix, 'U')] = U # to_lstm_U:(512,2048)
params[_p(prefix, 'b')] = np.zeros((4*dim,)).astype('float32') # to_lstm_b:(2048,)
return params
def encoder(tparams, layer0_input, filter_shape, pool_size,
prefix='cnn_encoder'):
""" filter_shape: (number of filters, num input feature maps, filter height,
filter width)
image_shape: (batch_size, num input feature maps, image height, image width)
"""
conv_out = conv.conv2d(input=layer0_input, filters=tparams[_p(prefix,'W')],
filter_shape=filter_shape)
conv_out_tanh = tensor.tanh(conv_out + tparams[_p(prefix,'b')].dimshuffle('x', 0, 'x', 'x'))
output = pool.pool_2d(input=conv_out_tanh, ds=pool_size, ignore_border=True)
return output.flatten(2)
def param_init(self):
if not self.initialized:
# call object specific param_init
self.__param_init__()
# set object params with theano shared
for (k, v) in self.params.iteritems():
setattr(self, k, theano.shared(
v, name=_p(self.get_prefix(), k), borrow=True))
# fill params with the theano shared
self._params = OrderedDict([
(_p(self.get_prefix(), k), getattr(self, k)) for (k, v) in
self.params.iteritems() if self.params])
self.initialized = True
return self.params
def _init_params(self):
shape_i0o = (self.n_in_0, self.n_out)
shape_i1o = (self.n_in_1, self.n_out)
if self.orth:
if self.n_in_0 != self.n_out or self.n_in_1 != self.n_out:
raise ValueError('n_in != n_out when require orth in FeedForward')
self.W0 = ortho_weight(rng=self.rng, shape=shape_i0o, name=_p(self.pname, 'W0'))
self.W1 = ortho_weight(rng=self.rng, shape=shape_i1o, name=_p(self.pname, 'W1'))
else:
self.W0 = norm_weight(rng=self.rng, shape=shape_i0o, name=_p(self.pname, 'W0'))
self.W1 = norm_weight(rng=self.rng, shape=shape_i1o, name=_p(self.pname, 'W1'))
self.b = constant_weight(shape=(self.n_out, ), name=_p(self.pname, 'b'))
self.params = [self.W0, self.W1, self.b]
def encoder(tparams, layer0_input, filter_shape, pool_size,
prefix='cnn_encoder'):
""" filter_shape: (number of filters, num input feature maps, filter height,
filter width)
image_shape: (batch_size, num input feature maps, image height, image width)
"""
conv_out = conv.conv2d(input=layer0_input, filters=tparams[_p(prefix,'W')],
filter_shape=filter_shape)
conv_out_tanh = tensor.tanh(conv_out + tparams[_p(prefix,'b')].dimshuffle('x', 0, 'x', 'x'))
output = pool.pool_2d(input=conv_out_tanh, ds=pool_size, ignore_border=True)
return output.flatten(2)
def lstm_layer(tparams, state_below, options, prefix='lstm', mask=None):
nsteps = state_below.shape[0]
if state_below.ndim == 3:
n_samples = state_below.shape[1]
else:
n_samples = 1
assert mask is not None
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n * dim:(n + 1) * dim]
return _x[:, n * dim:(n + 1) * dim]
def _step(m_, x_, h_, c_):
preact = tensor.dot(h_, tparams[_p(prefix, 'U')])
preact += x_
i = tensor.nnet.sigmoid(_slice(preact, 0, options['dim_proj']))
f = tensor.nnet.sigmoid(_slice(preact, 1, options['dim_proj']))
o = tensor.nnet.sigmoid(_slice(preact, 2, options['dim_proj']))
c = tensor.tanh(_slice(preact, 3, options['dim_proj']))
c = f * c_ + i * c
c = m_[:, None] * c + (1. - m_)[:, None] * c_
h = o * tensor.tanh(c)
h = m_[:, None] * h + (1. - m_)[:, None] * h_
return h, c
state_below = (tensor.dot(state_below, tparams[_p(prefix, 'W')]) +
tparams[_p(prefix, 'b')])
dim_proj = options['dim_proj']
rval, updates = theano.scan(_step,
sequences=[mask, state_below],
outputs_info=[
tensor.alloc(numpy_floatX(0.), n_samples,
dim_proj),
tensor.alloc(numpy_floatX(0.), n_samples,
dim_proj)
],
name=_p(prefix, '_layers'),
n_steps=nsteps)
# outputs_info include h_ and c_
# return only hidden states, so return rval[0]
return rval[0]
def action_response_layer(tparams, features, options, payoff=None,
prefix='ar', opposition=None, level=0, **kwargs):
"""
action_response_layer: tensor3, (tensor3) -> matrix
features, (opposition) -> ar_layer
Tensor dims:
features: iter, action_payoff, feature
opposition: iter, level, prob of action
output: iter, prob of action
Probability of an action given features and beliefs about opposition.
"""
n, f, i = features.shape
# Weights on opposition players
if level == 0:
w_feat = tparams[_p(prefix, 'Wf')]
weighted_features = tensor.sum(features * w_feat.dimshuffle('x', 0, 'x'), axis=1)
ar = weighted_features
return ar, weighted_features, None
else:
weighted_features = None
lam = tparams[_p(prefix, 'lam')]
if options['shared_ld']:
level_dist = tparams['ld']
ld = level_dist
ld += floatx(1e-32) # avoid divide by zero
ld = ld[0:level]
ld /= ld.sum()
else:
ld = tparams[_p(prefix, 'ld')]
ld += floatx(1e-32)
ld /= ld.sum()
# U * AR * ld (where * is matrix product)
weighting = opposition * ld.dimshuffle('x', 0, 'x')
prob_a = tensor.sum(weighting, axis=1)
payoff = payoff * tparams[_p(prefix, 'W_h')].dimshuffle('x', 0, 'x', 'x')
payoff = tensor.sum(payoff,axis=1)
br = tensor.sum(payoff * prob_a.dimshuffle(0, 'x', 1), axis=2)
out = br
# remove weighted_features, br when done with visualisation
return tensor.nnet.softmax(out * lam), weighted_features, br
def get_all_params(self, prev_prefix=None):
'''Return an OrderedDict with all the parameters.
Return an OrderedDict with the parameters of self and
of every child, renamed so that they contain the full
inclusion path in their name.
Corresponds to:
for k, v in self.params.iteritems():
part = [(k, v)]
for child in unroll(self.children):
if child:
for k, v in child.get_all_params().iteritems():
part += [(_p(self.get_prefix(), k), v)]
return OrderedDict(part)
'''
if prev_prefix:
self.baseprefix = _p(prev_prefix, self.baseprefix)
if self.children == []:
return self.param_init()
else:
return OrderedDict([(k, v)
for k, v in self.param_init().iteritems()] +
[(k, v)
for child in unroll(self.children) if child
for k, v in child.get_all_params(
self.get_prefix()).iteritems()])
def get_all_params(self, prev_prefix=None):
'''Return an OrderedDict with all the parameters.
Return an OrderedDict with the parameters of self and
of every child, renamed so that they contain the full
inclusion path in their name.
Corresponds to:
for k, v in self.params.iteritems():
part = [(k, v)]
for child in unroll(self.children):
if child:
for k, v in child.get_all_params().iteritems():
part += [(_p(self.get_prefix(), k), v)]
return OrderedDict(part)
'''
if prev_prefix:
self.baseprefix = _p(prev_prefix, self.baseprefix)
if self.children == []:
return self.param_init()
else:
return OrderedDict([
(k, v) for k, v in self.param_init().iteritems()] +
[(k, v) for child in
unroll(self.children) if child
for k, v in child.get_all_params(
self.get_prefix()).iteritems()])
def __init__(self, mkl, n_in, n_hids, n_cdim, maxout_part=2,
name='rnn_decoder',
with_attention=True,
with_coverage=False,
coverage_dim=1,
coverage_type='linguistic',
max_fertility=2,
with_context_gate=False):
self.n_in = n_in
self.n_hids = n_hids
self.n_cdim = n_cdim
self.maxout_part = maxout_part
self.pname = name
self.with_attention = with_attention
self.with_coverage = with_coverage
self.coverage_dim = coverage_dim
assert coverage_type in ['linguistic', 'neural'], 'Coverage type must be either linguistic or neural'
self.coverage_type = coverage_type
self.max_fertility = max_fertility
self.with_context_gate = with_context_gate
self.mkl = mkl
self._init_params()
#mkl decoder
self.attention_ = Attention_(self.n_hids, name=_p(name, '_attention'))
self.GRU_op = mkl_gru.GRU(hid=self.n_hids, return_sequences=True)
def param_init(params, nin, dim, prefix='lstm'):
assert prefix is not None
# Stack the weight matricies for faster dot prods
W = np.concatenate([norm_weight(nin,dim),
norm_weight(nin,dim),
norm_weight(nin,dim),
norm_weight(nin,dim)], axis=1)
params[_p(prefix, 'W')] = W
U = np.concatenate([ortho_weight(dim),
ortho_weight(dim),
ortho_weight(dim),
ortho_weight(dim)], axis=1)
params[_p(prefix, 'U')] = U
params[_p(prefix, 'b')] = np.zeros((4 * dim,)).astype('float32')
return params
def apply(self, state_below, mask_below=None, init_state=None, context=None):
if K.ndim(state_below) == 2:
state_below = K.expand_dims(state_below, 1)
if mask_below is None:
mask_below = K.ones_like(K.sum(state_below, axis=2, keepdims=True))
if init_state is None:
# nb_samples,n_hids
init_state = K.repeat_elements(K.expand_dims(K.zeros_like(K.sum(state_below, axis=[0, 2]))), self.n_hids, axis=1)
print('init state ',K.ndim(init_state))
state_below_xh = K. dot(state_below, self.W_xh)
state_below_xz = K. dot(state_below, self.W_xz)
state_below_xr = K.dot(state_below, self.W_xr)
sequences = [state_below_xh, state_below_xz, state_below_xr, mask_below]
if K._BACKEND == 'theano':
fn = lambda x_h, x_z, x_r, x_m, h_tm1: self._step(x_h, x_z, x_r, x_m, h_tm1)
else:
fn = lambda h_tm1, (x_h, x_z, x_r, x_m): self._step(x_h, x_z, x_r, x_m, h_tm1)
rval = K.scan(fn,
sequences=sequences,
outputs_initials=init_state,
name=_p(self.pname, 'layers'))
self.output = rval
return self.output
def _lstm(m_, x_, h_, c_, prefix='lstm_en'):
preact = tensor.dot(x_, tparams[_p(prefix, 'W')]) + tparams[_p(
prefix, 'b')]
preact += tensor.dot(h_, tparams[_p(prefix, 'U')])
i = tensor.nnet.sigmoid(_slice(preact, 0, options['dim_proj']))
f = tensor.nnet.sigmoid(_slice(preact, 1, options['dim_proj']))
o = tensor.nnet.sigmoid(_slice(preact, 2, options['dim_proj']))
c = tensor.tanh(_slice(preact, 3, options['dim_proj']))
c = f * c_ + i * c
c = m_[:, None] * c + (1. - m_)[:, None] * c_
h = o * tensor.tanh(c)
h = m_[:, None] * h + (1. - m_)[:, None] * h_
return h, c
def deconv_depool(layer0_input, tparams, options, prefix):
if prefix == 'd':
depool_out = depool_repeat(layer0_input, options['e_pool_size'])
elif prefix == 'd2':
depool_out = depool_repeat(layer0_input, options['e2_pool_size'])
s = int(np.floor(options[_p(prefix, 'Nt')] / 2.))
_W = get_filter(tparams, options, prefix).astype(theano.config.floatX)
deconv_out = conv.conv2d(input=depool_out.dimshuffle(0, 1, 'x', 2),
filters=_W,
filter_shape=options[_p(prefix, 'filter_shape')],
border_mode='full')[:, :, :, s - 1:-s]
doutput = (
deconv_out +
tparams[_p(prefix, 'bias')].dimshuffle('x', 0, 'x', 'x')).reshape(
(deconv_out.shape[0], options['C'], options['T']))
return doutput
def lstm_layer(tparams, state_below, options, prefix='lstm', mask=None):
nsteps = state_below.shape[0]
if state_below.ndim == 3:
n_samples = state_below.shape[1]
else:
n_samples = 1
assert mask is not None
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n * dim:(n+1) * dim]
return _x[:, n * dim:(n+1) * dim]
def _step(m_, x_, h_, c_):
preact = tensor.dot(h_, tparams[_p(prefix, 'U')])
preact += x_
i = tensor.nnet.sigmoid(_slice(preact, 0, options['dim_proj']))
f = tensor.nnet.sigmoid(_slice(preact, 1, options['dim_proj']))
o = tensor.nnet.sigmoid(_slice(preact, 2, options['dim_proj']))
c = tensor.tanh(_slice(preact, 3, options['dim_proj']))
c = f * c_ + i * c
c = m_[:, None] * c + (1. - m_)[:, None] * c_
h = o * tensor.tanh(c)
h = m_[:, None] * h + (1. - m_)[:, None] * h_
return h, c
state_below = (tensor.dot(state_below, tparams[_p(prefix, 'W')]) +
tparams[_p(prefix, 'b')])
dim_proj = options['dim_proj']
rval, updates = theano.scan(_step,
sequences=[mask, state_below],
outputs_info=[tensor.alloc(numpy_floatX(0.),
n_samples,
dim_proj),
tensor.alloc(numpy_floatX(0.),
n_samples,
dim_proj)],
name=_p(prefix, '_layers'),
n_steps=nsteps)
return rval[0][-1]
def decoder(tparams, state_below, z, mask=None, prefix='decoder'):
""" state_below: size of n_steps * n_samples * n_x
z: size of n_samples * n_z
"""
n_steps = state_below.shape[0]
n_samples = state_below.shape[1]
n_h = tparams[_p(prefix,'U')].shape[0]
# n_samples * n_h
state_belowx0 = tensor.dot(z, tparams[_p(prefix, 'C0')]) + \
tparams[_p(prefix, 'b0')]
h0 = tensor.tanh(state_belowx0)
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n*dim:(n+1)*dim]
return _x[:, n*dim:(n+1)*dim]
# n_steps * n_samples * n_h
state_below_ = tensor.dot(state_below, tparams[_p(prefix, 'W')]) + \
tensor.dot(z, tparams[_p(prefix, 'C')]) + tparams[_p(prefix, 'b')]
def _step(m_, x_, h_, c_, U):
preact = tensor.dot(h_, U)
preact += x_
i = tensor.nnet.sigmoid(_slice(preact, 0, n_h))
f = tensor.nnet.sigmoid(_slice(preact, 1, n_h))
o = tensor.nnet.sigmoid(_slice(preact, 2, n_h))
c = tensor.tanh(_slice(preact, 3, n_h))
c = f * c_ + i * c
c = m_[:, None] * c + (1. - m_)[:, None] * c_
h = o * tensor.tanh(c)
h = m_[:, None] * h + (1. - m_)[:, None] * h_
return h, c
seqs = [mask[:n_steps-1], state_below_[:n_steps-1]]
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info = [h0,tensor.alloc(numpy_floatX(0.),
n_samples,n_h)],
non_sequences = [tparams[_p(prefix, 'U')]],
name=_p(prefix, '_layers'),
n_steps=n_steps-1,
strict=True)
h0x = tensor.shape_padleft(h0)
h_rval = rval[0]
return tensor.concatenate((h0x,h_rval))
def apply(self, state_below, mask_below=None, init_state=None, context=None):
n_steps = state_below.shape[0]
if state_below.ndim == 3:
batch_size = state_below.shape[1]
else:
batch_size = 1
state_below = state_below.reshape((n_steps, batch_size, state_below.shape[1]))
if mask_below is None:
mask_below = T.alloc(numpy.float32(1.), n_steps, 1)
if self.with_context:
assert context
if init_state is None:
init_state = T.tanh(T.dot(context, self.W_c_init))
c_z = T.dot(context, self.W_cz)
c_r = T.dot(context, self.W_cr)
c_h = T.dot(context, self.W_ch)
non_sequences = [c_z, c_r, c_h]
rval, updates = theano.scan(self._step_context,
sequences=[state_below, mask_below],
non_sequences=non_sequences,
outputs_info=[init_state],
name=_p(self.pname, 'layers'),
n_steps=n_steps)
else:
if init_state is None:
init_state = T.alloc(numpy.float32(0.), batch_size, self.n_hids)
state_below_xh = T.dot(state_below, self.W_xh)
state_below_xz = T.dot(state_below, self.W_xz)
state_below_xr = T.dot(state_below, self.W_xr)
sequences = [state_below_xh, state_below_xz, state_below_xr, mask_below]
rval, updates = theano.scan(self._step,
sequences=sequences,
outputs_info=[init_state],
name=_p(self.pname, 'layers'),
n_steps=n_steps)
self.output = rval
return self.output
def build_encoder(tparams, options):
x = tensor.matrix('x', dtype='int32')
y = tensor.matrix('y', dtype='int32')
layer0_input = tparams['Wemb'][tensor.cast(x.flatten(),
dtype='int32')].reshape(
(x.shape[0], 1, x.shape[1],
tparams['Wemb'].shape[1]))
layer1_inputs = []
for i in xrange(len(options['filter_hs'])):
filter_shape = options['filter_shapes'][i]
pool_size = options['pool_sizes'][i]
conv_layer = encoder(tparams,
layer0_input,
filter_shape=filter_shape,
pool_size=pool_size,
prefix=_p('cnn_encoder', i))
layer1_input = conv_layer
layer1_inputs.append(layer1_input)
layer1_input_x = tensor.concatenate(layer1_inputs, 1)
layer0_input = tparams['Wemb'][tensor.cast(y.flatten(),
dtype='int32')].reshape(
(y.shape[0], 1, y.shape[1],
tparams['Wemb'].shape[1]))
layer1_inputs = []
for i in xrange(len(options['filter_hs'])):
filter_shape = options['filter_shapes'][i]
pool_size = options['pool_sizes'][i]
conv_layer = encoder(tparams,
layer0_input,
filter_shape=filter_shape,
pool_size=pool_size,
prefix=_p('cnn_encoder', i))
layer1_input = conv_layer
layer1_inputs.append(layer1_input)
layer1_input_y = tensor.concatenate(layer1_inputs, 1)
feat_x = l2norm(layer1_input_x)
feat_y = l2norm(layer1_input_y)
return [x, y], feat_x, feat_y
def param_init_decoder(options, params, prefix='decoder_gru'):
n_x = options['n_x']
n_h = options['n_h']
W = np.concatenate([uniform_weight(n_x, n_h),
uniform_weight(n_x, n_h)],
axis=1)
params[_p(prefix, 'W')] = W
U = np.concatenate([ortho_weight(n_h), ortho_weight(n_h)], axis=1)
params[_p(prefix, 'U')] = U
params[_p(prefix, 'b')] = zero_bias(2 * n_h)
Wx = uniform_weight(n_x, n_h)
params[_p(prefix, 'Wx')] = Wx
Ux = ortho_weight(n_h)
params[_p(prefix, 'Ux')] = Ux
params[_p(prefix, 'bx')] = zero_bias(n_h)
params[_p(prefix, 'b0')] = zero_bias(n_h)
return params
def decoder_layer(tparams, state_below, prefix='decoder_gru'):
""" state_below: size of n_steps * n_x
"""
n_steps = state_below.shape[0]
n_h = tparams[_p(prefix, 'Ux')].shape[1]
state_belowx0 = tparams[_p(prefix, 'b0')]
h0vec = tensor.tanh(state_belowx0)
h0 = h0vec.dimshuffle('x', 0)
def _slice(_x, n, dim):
return _x[n * dim:(n + 1) * dim]
state_below_ = tensor.dot(state_below, tparams[_p(
prefix, 'W')]) + tparams[_p(prefix, 'b')]
state_belowx = tensor.dot(state_below, tparams[_p(
prefix, 'Wx')]) + tparams[_p(prefix, 'bx')]
def _step_slice(x_, xx_, h_, U, Ux):
preact = tensor.dot(h_, U)
preact += x_
r = tensor.nnet.sigmoid(_slice(preact, 0, n_h))
u = tensor.nnet.sigmoid(_slice(preact, 1, n_h))
preactx = tensor.dot(h_, Ux)
preactx = preactx * r
preactx = preactx + xx_
h = tensor.tanh(preactx)
h = u * h_ + (1. - u) * h
return h
seqs = [state_below_[:n_steps - 1], state_belowx[:n_steps - 1]]
_step = _step_slice
rval, updates = theano.scan(
_step,
sequences=seqs,
outputs_info=[h0vec],
non_sequences=[tparams[_p(prefix, 'U')], tparams[_p(prefix, 'Ux')]],
name=_p(prefix, '_layers'),
n_steps=n_steps - 1)
#h0x = h0.dimshuffle('x',0,1)
return tensor.concatenate((h0, rval))
def param_init_decoder(options, params, prefix='decoder_gru'):
n_x = options['n_x']
n_h = options['n_h']
W = np.concatenate([uniform_weight(n_x,n_h),
uniform_weight(n_x,n_h)], axis=1)
params[_p(prefix,'W')] = W
U = np.concatenate([ortho_weight(n_h),
ortho_weight(n_h)], axis=1)
params[_p(prefix,'U')] = U
params[_p(prefix,'b')] = zero_bias(2*n_h)
Wx = uniform_weight(n_x, n_h)
params[_p(prefix,'Wx')] = Wx
Ux = ortho_weight(n_h)
params[_p(prefix,'Ux')] = Ux
params[_p(prefix,'bx')] = zero_bias(n_h)
params[_p(prefix,'b0')] = zero_bias(n_h)
return params
def decoder_layer(tparams, state_below, prefix='decoder_gru'):
""" state_below: size of n_steps * n_x
"""
n_steps = state_below.shape[0]
n_h = tparams[_p(prefix,'Ux')].shape[1]
state_belowx0 = tparams[_p(prefix, 'b0')]
h0vec = tensor.tanh(state_belowx0)
h0 = h0vec.dimshuffle('x',0)
def _slice(_x, n, dim):
return _x[n*dim:(n+1)*dim]
state_below_ = tensor.dot(state_below, tparams[_p(prefix, 'W')]) + tparams[_p(prefix, 'b')]
state_belowx = tensor.dot(state_below, tparams[_p(prefix, 'Wx')]) + tparams[_p(prefix, 'bx')]
def _step_slice(x_, xx_, h_, U, Ux):
preact = tensor.dot(h_, U)
preact += x_
r = tensor.nnet.sigmoid(_slice(preact, 0, n_h))
u = tensor.nnet.sigmoid(_slice(preact, 1, n_h))
preactx = tensor.dot(h_, Ux)
preactx = preactx * r
preactx = preactx + xx_
h = tensor.tanh(preactx)
h = u * h_ + (1. - u) * h
return h
seqs = [state_below_[:n_steps-1], state_belowx[:n_steps-1]]
_step = _step_slice
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info = [h0vec],
non_sequences = [tparams[_p(prefix, 'U')],
tparams[_p(prefix, 'Ux')]],
name=_p(prefix, '_layers'),
n_steps=n_steps-1)
#h0x = h0.dimshuffle('x',0,1)
return tensor.concatenate((h0,rval))
def __init__(self,
n_in,
n_hids,
table,
mkl,
name='rnn_encoder',
max_len=None):
# lookup table
self.table = table
# embedding dimension
self.n_in = n_in
# hidden state dimension
self.n_hids = n_hids
self.mkl = mkl
self.params = []
self.layers = []
self.max_len = max_len
if self.mkl == True:
print('with mkl')
self.forward = MKL_GRU(self.n_in,
self.n_hids,
name=_p(name, 'forward'),
max_len=max_len)
else:
print('with no mkl')
self.forward = GRU(self.n_in,
self.n_hids,
name=_p(name, 'forward'))
self.layers.append(self.forward)
if self.mkl == True:
self.backward = MKL_GRU(self.n_in,
self.n_hids,
name=_p(name, 'backward'),
max_len=max_len)
else:
self.backward = GRU(self.n_in,
self.n_hids,
name=_p(name, 'backward'))
self.layers.append(self.backward)
for layer in self.layers:
self.params.extend(layer.params)
def encoder(tparams, state_below, mask, seq_output=False, prefix='gru_encoder'):
""" state_below: size of n_steps * n_samples * n_x
"""
n_steps = state_below.shape[0]
n_samples = state_below.shape[1]
n_h = tparams[_p(prefix,'Ux')].shape[1]
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n*dim:(n+1)*dim]
return _x[:, n*dim:(n+1)*dim]
state_below_ = tensor.dot(state_below, tparams[_p(prefix, 'W')]) + \
tparams[_p(prefix, 'b')]
state_belowx = tensor.dot(state_below, tparams[_p(prefix, 'Wx')]) + \
tparams[_p(prefix, 'bx')]
def _step(m_, x_, xx_, h_, U, Ux):
preact = tensor.dot(h_, U)
preact += x_
r = tensor.nnet.sigmoid(_slice(preact, 0, n_h))
u = tensor.nnet.sigmoid(_slice(preact, 1, n_h))
preactx = tensor.dot(h_, Ux)
preactx = preactx * r
preactx = preactx + xx_
h = tensor.tanh(preactx)
h = u * h_ + (1. - u) * h
h = m_[:,None] * h + (1. - m_)[:,None] * h_
return h
seqs = [mask, state_below_, state_belowx]
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info = [tensor.alloc(numpy_floatX(0.),
n_samples, n_h)],
non_sequences = [tparams[_p(prefix, 'U')],
tparams[_p(prefix, 'Ux')]],
name=_p(prefix, '_layers'),
n_steps=n_steps,
strict=True)
if seq_output:
return rval
else:
# size of n_samples * n_h
return rval[-1]
def param_init(self):
if not self.initialized:
# call object specific param_init
self.__param_init__()
# set object params with theano shared
for (k, v) in self.params.iteritems():
setattr(
self, k,
theano.shared(v,
name=_p(self.get_prefix(), k),
borrow=True))
# fill params with the theano shared
self._params = OrderedDict([(_p(self.get_prefix(),
k), getattr(self, k))
for (k, v) in self.params.iteritems()
if self.params])
self.initialized = True
return self.params
def param_init_gru(options, params, prefix='gru', nin=None, dim=None):
if nin is None:
nin = options['dim_proj']
if dim is None:
dim = options['dim_proj']
# embedding to gates transformation weights, biases
W = np.concatenate([norm_weight(nin, dim),
norm_weight(nin, dim)], axis=1)
params[_p(prefix, 'W')] = W
params[_p(prefix, 'b')] = np.zeros((2 * dim,)).astype('float32')
# recurrent transformation weights for gates
U = np.concatenate([ortho_weight(dim),
ortho_weight(dim)], axis=1)
params[_p(prefix, 'U')] = U
# embedding to hidden state proposal weights, biases
Wx = norm_weight(nin, dim)
params[_p(prefix, 'Wx')] = Wx
params[_p(prefix, 'bx')] = np.zeros((dim,)).astype('float32')
# recurrent transformation weights for hidden state proposal
Ux = ortho_weight(dim)
params[_p(prefix, 'Ux')] = Ux
return params
def _init_params(self):
shape_xh = (self.n_in, self.n_hids)
shape_xh4 = (self.n_in, 4*self.n_hids)
shape_hh = (self.n_hids, self.n_hids)
shape_hh4 = (self.n_hids, 4*self.n_hids)
self.W_pre_x = norm_weight(rng=self.rng, shape=shape_xh4, name=_p(self.pname, 'W_pre_x'))
self.W_h = multi_orth(rng=self.rng, size=shape_hh4, name=_p(self.pname, 'W_h'))
b_i = constant_weight(share=False, shape=(self.n_hids, ), name=_p(self.pname, 'b_i'))
b_f = constant_weight(share=False, value=1., shape=(self.n_hids, ), name=_p(self.pname, 'b_f'))
b_o = constant_weight(share=False, shape=(self.n_hids, ), name=_p(self.pname, 'b_o'))
b_c = constant_weight(share=False, shape=(self.n_hids, ), name=_p(self.pname, 'b_c'))
b_ifoc = numpy.concatenate([b_i, b_f, b_o, b_c], axis=0)
self.b_pre_x = theano.shared(value=b_ifoc, borrow=True, name=_p(self.pname, 'b_pre_x'))
self.params += [self.W_pre_x, self.W_h, self.b_pre_x]
if self.with_context:
raise NotImplementedError
if self.with_begin_tag:
self.struct_begin_tag = constant_weight(shape=(self.n_hids,), value=0., name=_p(self.pname, 'struct_begin_tag'))
self.params += [self.struct_begin_tag]
if self.with_end_tag:
self.struct_end_tag = constant_weight(shape=(self.n_in,), value=0., name=_p(self.pname, 'struct_end_tag'))
self.params += [self.struct_end_tag]
if self.n_att_ctx:
self.lstm_combine_ctx_h = LSTM(self.n_att_ctx, self.n_hids, rng=self.rng, name=_p(self.pname, 'lstm_combine_ctx_h'))
self.params.extend(self.lstm_combine_ctx_h.params)
self.attention = ATTENTION(self.n_hids, self.rng, name=_p(self.pname, 'att_ctx'))
self.params.extend(self.attention.params)
if self.seq_pyramid:
self.pyramid_on_seq = LSTM(self.n_att_ctx, self.n_att_ctx, rng=self.rng, name=_p(self.pname, 'pyramid_on_seq'))
self.params.extend(self.pyramid_on_seq.params)
self.ff_pyramid2ctx = FeedForward(self.n_att_ctx, self.n_hids, name=_p(self.pname, 'ff_pyramid2ctx'))
self.params.extend(self.ff_pyramid2ctx.params)
def apply_seq_pyramid(self, state_below,
state_below_p,
mask_below=None,
init_state_h=None,
init_state_c=None,
init_state_hp=None,
init_state_cp=None,
context=None):
'''
state_below: shape=[seq_len, batch, n_in]
state_below_p: shape=[seq_len, batch, n_in_p]
init_state: shape=[batch, seq_len, hid]
'''
n_steps = state_below.shape[0]
if state_below.ndim == 3:
batch_size = state_below.shape[1]
else:
batch_size = 1
state_below = state_below.reshape((n_steps, batch_size, state_below.shape[1]))
state_below_p = state_below_p.reshape((n_steps, batch_size, state_below_p.shape[1]))
if mask_below is None:
mask_below = T.alloc(numpy.float32(1.), n_steps, 1)
if self.with_context:
raise NotImplementedError
else:
if init_state_h is None:
init_state_h = T.alloc(numpy.float32(0.), batch_size, self.n_hids)
if init_state_c is None:
init_state_c = T.alloc(numpy.float32(0.), batch_size, self.n_hids)
if init_state_hp is None:
init_state_hp = T.alloc(numpy.float32(0.), batch_size, n_steps, self.n_hids)
if init_state_cp is None:
init_state_cp = T.alloc(numpy.float32(0.), batch_size, n_steps, self.n_hids)
state_below_pre = T.dot(state_below, self.W_pre_x) + self.b_pre_x
state_below_p_pre = T.dot(state_below_p, self.pyramid_on_seq.W_pre_x) + self.pyramid_on_seq.b_pre_x
step_idx = T.arange(n_steps)
sequences = [state_below_pre, state_below_p_pre, mask_below, step_idx]
outputs_info = [init_state_h, init_state_c, init_state_hp, init_state_cp]
non_sequences = []
rval, updates = theano.scan(self._seq_pyramid_step,
sequences=sequences,
outputs_info=outputs_info,
non_sequences=non_sequences,
name=_p(self.pname, 'layers'),
n_steps=n_steps)
self.output = rval
return self.output
def param_init_lstm(options, params, prefix='lstm'):
"""Init the LSTM parameter
:options: TODO
:params: TODO
:prefix: TODO
:returns: TODO
"""
W = numpy.concatenate([ortho_weight(options['dim_proj']),
ortho_weight(options['dim_proj']),
ortho_weight(options['dim_proj']),
ortho_weight(options['dim_proj'])], axis=1)
params[_p(prefix, 'W')] = W
U = numpy.concatenate([ortho_weight(options['dim_proj']),
ortho_weight(options['dim_proj']),
ortho_weight(options['dim_proj']),
ortho_weight(options['dim_proj'])], axis=1)
params[_p(prefix, 'U')] = U
b = numpy.zeros((4 * options['dim_proj'],))
params[_p(prefix, 'b')] = b.astype(config.floatX)
return params
def _step(m_, x_, h_, c_):
preact = tensor.dot(h_, tparams[_p(prefix, 'U')])
preact += x_
i = tensor.nnet.sigmoid(_slice(preact, 0, options['dim_proj']))
f = tensor.nnet.sigmoid(_slice(preact, 1, options['dim_proj']))
o = tensor.nnet.sigmoid(_slice(preact, 2, options['dim_proj']))
c = tensor.tanh(_slice(preact, 3, options['dim_proj']))
c = f * c_ + i * c
c = m_[:, None] * c + (1. - m_)[:, None] * c_
h = o * tensor.tanh(c)
h = m_[:, None] * h + (1. - m_)[:, None] * h_
return h, c
def init_params(options,W):
params = OrderedDict()
# W is initialized by the pretrained word embedding
params['Wemb'] = W.astype(config.floatX)
# otherwise, W will be initialized randomly
# n_words = options['n_words']
# n_x = options['n_x']
# params['Wemb'] = uniform_weight(n_words,n_x)
length = len(options['filter_shapes'])
for idx in range(length):
params = param_init_encoder(options['filter_shapes'][idx],params,prefix=_p('cnn_encoder',idx))
n_h = options['feature_maps'] * length
params['Wy'] = uniform_weight(n_h,options['n_y'])
params['by'] = zero_bias(options['n_y'])
return params
def param_init_gru(options, params, prefix='gru', nin=None, dim=None):
"""
Gated Recurrent Unit (GRU)
"""
if nin == None:
nin = options['dim_proj']
if dim == None:
dim = options['dim_proj']
W = numpy.concatenate([norm_weight(nin,dim),
norm_weight(nin,dim)], axis=1)
params[_p(prefix,'W')] = W
params[_p(prefix,'b')] = numpy.zeros((2 * dim,)).astype('float32')
U = numpy.concatenate([ortho_weight(dim),
ortho_weight(dim)], axis=1)
params[_p(prefix,'U')] = U
Wx = norm_weight(nin, dim)
params[_p(prefix,'Wx')] = Wx
Ux = ortho_weight(dim)
params[_p(prefix,'Ux')] = Ux
params[_p(prefix,'bx')] = numpy.zeros((dim,)).astype('float32')
return params
def gru_cond_layer(tparams, state_below, options, prefix='gru',
mask=None, context=None, one_step=False,
init_memory=None, init_state=None,
context_mask=None,
**kwargs):
assert context, 'Context must be provided'
if one_step:
assert init_state, 'previous state must be provided'
nsteps = state_below.shape[0]
if state_below.ndim == 3:
n_samples = state_below.shape[1]
else:
n_samples = 1
# mask
if mask is None:
mask = tensor.alloc(1., state_below.shape[0], 1)
dim = tparams[_p(prefix, 'Wcx')].shape[1]
# initial/previous state
if init_state is None:
init_state = tensor.alloc(0., n_samples, dim)
# projected context
assert context.ndim == 3, \
'Context must be 3-d: #annotation x #sample x dim'
pctx_ = tensor.dot(context, tparams[_p(prefix, 'Wc_att')]) + \
tparams[_p(prefix, 'b_att')]
def _slice(_x, n, dim):
if _x.ndim == 3:
return _x[:, :, n * dim:(n + 1) * dim]
return _x[:, n * dim:(n + 1) * dim]
# projected x
state_belowx = tensor.dot(state_below, tparams[_p(prefix, 'Wx')]) + \
tparams[_p(prefix, 'bx')]
state_below_ = tensor.dot(state_below, tparams[_p(prefix, 'W')]) + \
tparams[_p(prefix, 'b')]
def _step_slice(m_, x_, xx_, h_, ctx_, alpha_, pctx_, cc_,
U, Wc, W_comb_att, U_att, c_tt, Ux, Wcx,
U_nl, Ux_nl, b_nl, bx_nl):
preact1 = tensor.dot(h_, U)
preact1 += x_
preact1 = tensor.nnet.sigmoid(preact1)
r1 = _slice(preact1, 0, dim)
u1 = _slice(preact1, 1, dim)
preactx1 = tensor.dot(h_, Ux)
preactx1 *= r1
preactx1 += xx_
h1 = tensor.tanh(preactx1)
h1 = u1 * h_ + (1. - u1) * h1
h1 = m_[:, None] * h1 + (1. - m_)[:, None] * h_
# attention
pstate_ = tensor.dot(h1, W_comb_att)
pctx__ = pctx_ + pstate_[None, :, :]
# pctx__ += xc_
pctx__ = tensor.tanh(pctx__)
alpha = tensor.dot(pctx__, U_att) + c_tt
alpha = alpha.reshape([alpha.shape[0], alpha.shape[1]])
alpha = tensor.exp(alpha)
if context_mask:
alpha = alpha * context_mask
alpha = alpha / alpha.sum(0, keepdims=True)
ctx_ = (cc_ * alpha[:, :, None]).sum(0) # current context
preact2 = tensor.dot(h1, U_nl) + b_nl
preact2 += tensor.dot(ctx_, Wc)
preact2 = tensor.nnet.sigmoid(preact2)
r2 = _slice(preact2, 0, dim)
u2 = _slice(preact2, 1, dim)
preactx2 = tensor.dot(h1, Ux_nl) + bx_nl
preactx2 *= r2
preactx2 += tensor.dot(ctx_, Wcx)
h2 = tensor.tanh(preactx2)
h2 = u2 * h1 + (1. - u2) * h2
h2 = m_[:, None] * h2 + (1. - m_)[:, None] * h1
return h2, ctx_, alpha.T # pstate_, preact, preactx, r, u
seqs = [mask, state_below_, state_belowx]
# seqs = [mask, state_below_, state_belowx, state_belowc]
_step = _step_slice
shared_vars = [tparams[_p(prefix, 'U')],
tparams[_p(prefix, 'Wc')],
tparams[_p(prefix, 'W_comb_att')],
tparams[_p(prefix, 'U_att')],
tparams[_p(prefix, 'c_tt')],
tparams[_p(prefix, 'Ux')],
tparams[_p(prefix, 'Wcx')],
tparams[_p(prefix, 'U_nl')],
tparams[_p(prefix, 'Ux_nl')],
tparams[_p(prefix, 'b_nl')],
tparams[_p(prefix, 'bx_nl')]]
if one_step:
rval = _step(*(seqs + [init_state, None, None, pctx_, context] +
shared_vars))
else:
rval, updates = theano.scan(_step,
sequences=seqs,
outputs_info=[init_state,
tensor.alloc(0., n_samples,
context.shape[2]),
tensor.alloc(0., n_samples,
context.shape[0])],
non_sequences=[pctx_, context] + shared_vars,
name=_p(prefix, '_layers'),
n_steps=nsteps,
profile=profile,
strict=True)
return rval
def get_prefix(self):
if self.prefix is '':
return self.baseprefix
else:
return _p(self.baseprefix, self.prefix)
def _pname(self, name):
return _p(self.get_prefix(), name)
def _init_params(self):
shape_xh = (self.n_in, self.n_hids)
shape_xh2 = (self.n_in, 2*self.n_hids)
shape_hh = (self.n_hids, self.n_hids)
shape_hh2 = (self.n_hids, 2*self.n_hids)
self.W_xzr = norm_weight(rng=self.rng, shape=shape_xh2, name=_p(self.pname, 'W_xzr'))
self.W_xh = norm_weight(rng=self.rng, shape=shape_xh, name=_p(self.pname, 'W_xh'))
self.b_zr = constant_weight(shape=(2*self.n_hids, ), name=_p(self.pname, 'b_zr'))
self.b_h = constant_weight(shape=(self.n_hids, ), name=_p(self.pname, 'b_h'))
self.W_hzr = multi_orth(rng=self.rng, size=shape_hh2, name=_p(self.pname, 'W_hzr'))
self.W_hh = ortho_weight(rng=self.rng, shape=shape_hh, name=_p(self.pname, 'W_hh'))
self.params += [self.W_xzr, self.W_xh,
self.W_hzr, self.W_hh,
self.b_zr, self.b_h]
if self.with_context:
shape_ch = (self.c_hids, self.n_hids)
self.W_cz = norm_weight(rng=self.rng, shape=shape_ch, name=_p(self.pname, 'W_cz'))
self.W_cr = norm_weight(rng=self.rng, shape=shape_ch, name=_p(self.pname, 'W_cr'))
self.W_ch = norm_weight(rng=self.rng, shape=shape_ch, name=_p(self.pname, 'W_ch'))
self.W_c_init = norm_weight(rng=self.rng, shape=shape_ch, name=_p(self.pname, 'W_c_init'))
self.params += [self.W_cz, self.W_cr, self.W_ch, self.W_c_init]
if self.with_begin_tag:
self.struct_begin_tag = constant_weight(shape=(self.n_hids,), value=0., name=_p(self.pname, 'struct_begin_tag'))
self.params += [self.struct_begin_tag]
if self.with_end_tag:
self.struct_end_tag = constant_weight(shape=(self.n_in,), value=0., name=_p(self.pname, 'struct_end_tag'))
self.params += [self.struct_end_tag]
if self.n_att_ctx:
self.gru_combine_ctx_h = GRU(self.n_att_ctx, self.n_hids, rng=self.rng, name=_p(self.pname, 'gru_combine_ctx_h'))
self.params.extend(self.gru_combine_ctx_h.params)
self.attention = ATTENTION(self.n_hids, self.rng, name=_p(self.pname, 'att_ctx'))
self.params.extend(self.attention.params)
def _init_params(self):
shape_hh = (self.n_hids, self.n_hids)
self.W_comb_att = norm_weight(rng=self.rng, shape=shape_hh, name=_p(self.pname, 'W_comb_att'))
self.U_att = norm_weight(rng=self.rng, shape=(self.n_hids, 1), name=_p(self.pname, 'U_att'))
self.c_att = constant_weight(shape=(1,), name=_p(self.pname, 'c_att'))
self.params = [self.W_comb_att, self.U_att, self.c_att]
def fflayer(tparams, state_below, options, prefix='rconv', activ='lambda x: tensor.tanh(x)', **kwargs):
"""
Feedforward pass
"""
return eval(activ)(tensor.dot(state_below, tparams[_p(prefix,'W')])+tparams[_p(prefix,'b')])
def param_init_gru_cond(options, params, prefix='gru_cond',
nin=None, dim=None, dimctx=None,
nin_nonlin=None, dim_nonlin=None):
if nin is None:
nin = options['dim']
if dim is None:
dim = options['dim']
if dimctx is None:
dimctx = options['dim']
if nin_nonlin is None:
nin_nonlin = nin
if dim_nonlin is None:
dim_nonlin = dim
W = np.concatenate([norm_weight(nin, dim),
norm_weight(nin, dim)], axis=1)
params[_p(prefix, 'W')] = W
params[_p(prefix, 'b')] = np.zeros((2 * dim,)).astype('float32')
U = np.concatenate([ortho_weight(dim_nonlin),
ortho_weight(dim_nonlin)], axis=1)
params[_p(prefix, 'U')] = U
Wx = norm_weight(nin_nonlin, dim_nonlin)
params[_p(prefix, 'Wx')] = Wx
Ux = ortho_weight(dim_nonlin)
params[_p(prefix, 'Ux')] = Ux
params[_p(prefix, 'bx')] = np.zeros((dim_nonlin,)).astype('float32')
U_nl = np.concatenate([ortho_weight(dim_nonlin),
ortho_weight(dim_nonlin)], axis=1)
params[_p(prefix, 'U_nl')] = U_nl
params[_p(prefix, 'b_nl')] = np.zeros((2 * dim_nonlin,)).astype('float32')
Ux_nl = ortho_weight(dim_nonlin)
params[_p(prefix, 'Ux_nl')] = Ux_nl
params[_p(prefix, 'bx_nl')] = np.zeros((dim_nonlin,)).astype('float32')
# context to LSTM
Wc = norm_weight(dimctx, dim * 2)
params[_p(prefix, 'Wc')] = Wc
Wcx = norm_weight(dimctx, dim)
params[_p(prefix, 'Wcx')] = Wcx
# attention: combined -> hidden
W_comb_att = norm_weight(dim, dimctx)
params[_p(prefix, 'W_comb_att')] = W_comb_att
# attention: context -> hidden
Wc_att = norm_weight(dimctx)
params[_p(prefix, 'Wc_att')] = Wc_att
# attention: hidden bias
b_att = np.zeros((dimctx,)).astype('float32')
params[_p(prefix, 'b_att')] = b_att
# attention:
U_att = norm_weight(dimctx, 1)
params[_p(prefix, 'U_att')] = U_att
c_att = np.zeros((1,)).astype('float32')
params[_p(prefix, 'c_tt')] = c_att
return params