-
Notifications
You must be signed in to change notification settings - Fork 0
/
rrnn.py
471 lines (383 loc) · 17.9 KB
/
rrnn.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
"""
A nearly direct translation of Andrej's code
https://github.com/karpathy/char-rnn
"""
from __future__ import division
import cgt
from cgt import nn, utils, profiler
import numpy as np, numpy.random as nr
import os.path as osp
import argparse
from time import time
from StringIO import StringIO
from param_collection import ParamCollection
from IPython import embed
from numpy.linalg import norm
# via https://github.com/karpathy/char-rnn/blob/master/model/GRU.lua
# via http://arxiv.org/pdf/1412.3555v1.pdf
def make_deep_gru(size_input, size_mem, n_layers, size_output, size_batch):
inputs = [cgt.matrix() for i_layer in xrange(n_layers+1)]
outputs = []
for i_layer in xrange(n_layers):
prev_h = inputs[i_layer+1] # note that inputs[0] is the external input, so we add 1
x = inputs[0] if i_layer==0 else outputs[i_layer-1]
size_x = size_input if i_layer==0 else size_mem
update_gate = cgt.sigmoid(
nn.Affine(size_x, size_mem,name="i2u")(x)
+ nn.Affine(size_mem, size_mem, name="h2u")(prev_h))
reset_gate = cgt.sigmoid(
nn.Affine(size_x, size_mem,name="i2r")(x)
+ nn.Affine(size_mem, size_mem, name="h2r")(prev_h))
gated_hidden = reset_gate * prev_h
p2 = nn.Affine(size_mem, size_mem)(gated_hidden)
p1 = nn.Affine(size_x, size_mem)(x)
hidden_target = cgt.tanh(p1+p2)
next_h = (1.0-update_gate)*prev_h + update_gate*hidden_target
outputs.append(next_h)
category_activations = nn.Affine(size_mem, size_output,name="pred")(outputs[-1])
logprobs = nn.logsoftmax(category_activations)
outputs.append(logprobs)
return nn.Module(inputs, outputs)
def make_deep_lstm(size_input, size_mem, n_layers, size_output, size_batch):
inputs = [cgt.matrix(fixed_shape=(size_batch, size_input))]
for _ in xrange(2*n_layers):
inputs.append(cgt.matrix(fixed_shape=(size_batch, size_mem)))
outputs = []
for i_layer in xrange(n_layers):
prev_h = inputs[i_layer*2]
prev_c = inputs[i_layer*2+1]
if i_layer==0:
x = inputs[0]
size_x = size_input
else:
x = outputs[(i_layer-1)*2]
size_x = size_mem
input_sums = nn.Affine(size_x, 4*size_mem)(x) + nn.Affine(size_x, 4*size_mem)(prev_h)
sigmoid_chunk = cgt.sigmoid(input_sums[:,0:3*size_mem])
in_gate = sigmoid_chunk[:,0:size_mem]
forget_gate = sigmoid_chunk[:,size_mem:2*size_mem]
out_gate = sigmoid_chunk[:,2*size_mem:3*size_mem]
in_transform = cgt.tanh(input_sums[:,3*size_mem:4*size_mem])
next_c = forget_gate*prev_c + in_gate * in_transform
next_h = out_gate*cgt.tanh(next_c)
outputs.append(next_c)
outputs.append(next_h)
category_activations = nn.Affine(size_mem, size_output)(outputs[-1])
logprobs = nn.logsoftmax(category_activations)
outputs.append(logprobs)
return nn.Module(inputs, outputs)
def make_deep_rrnn_rot_relu(size_input, size_mem, n_layers, size_output, size_batch_in, k_in, k_h):
inputs = [cgt.matrix() for i_layer in xrange(n_layers+1)]
outputs = []
print 'input_size: ', size_input
for i_layer in xrange(n_layers):
prev_h = inputs[i_layer+1] # note that inputs[0] is the external input, so we add 1
x = inputs[0] if i_layer==0 else outputs[i_layer-1]
size_x = size_input if i_layer==0 else size_mem
size_batch = prev_h.shape[0]
xform_h_param = nn.TensorParam((2 * k_h, size_mem), name="rotxform")
xform_h_non = xform_h_param.weight
xform_h_non.props["is_rotation"] = True
xform_h_norm = cgt.norm(xform_h_non, axis=1, keepdims=True)
xform_h = cgt.broadcast('/', xform_h_non, xform_h_norm, "xx,x1")
add_in_lin = nn.Affine(size_x, size_mem)(x)
add_in_relu = nn.rectify(add_in_lin)
prev_h_scaled = nn.scale_mag(prev_h)
h_in_added = prev_h_scaled + add_in_relu
inters_h = [h_in_added]
colon = slice(None, None, None)
for i in xrange(2 * k_h):
inter_in = inters_h[-1]
r_cur = xform_h[i, :]
#r_cur = cgt.subtensor(xform_h, [i, colon])
r_cur_2_transpose = cgt.reshape(r_cur, (size_mem, 1))
r_cur_2 = cgt.reshape(r_cur, (1, size_mem))
ref_cur = cgt.dot(cgt.dot(inter_in, r_cur_2_transpose), r_cur_2)
inter_out = inter_in - 2 * ref_cur
inters_h.append(inter_out)
next_h = inters_h[-1]
outputs.append(next_h)
category_activations = nn.Affine(size_mem, size_output,name="pred")(outputs[-1])
logprobs = nn.logsoftmax(category_activations)
outputs.append(logprobs)
#print 'len outputs:', len(outputs)
#print 'len inputs:', len(inputs)
return nn.Module(inputs, outputs)
def make_deep_rrnn(size_input, size_mem, n_layers, size_output, size_batch_in, k_in, k_h):
inputs = [cgt.matrix() for i_layer in xrange(n_layers+1)]
outputs = []
print 'input_size: ', size_input
for i_layer in xrange(n_layers):
prev_h = inputs[i_layer+1] # note that inputs[0] is the external input, so we add 1
x = inputs[0] if i_layer==0 else outputs[i_layer-1]
size_x = size_input if i_layer==0 else size_mem
size_batch = prev_h.shape[0]
xform_h_param = nn.TensorParam((2 * k_h, size_mem), name="rotxform")
xform_h_non = xform_h_param.weight
xform_h_non.props["is_rotation"] = True
xform_h_norm = cgt.norm(xform_h_non, axis=1, keepdims=True)
xform_h = cgt.broadcast('/', xform_h_non, xform_h_norm, "xx,x1")
r_vec = nn.Affine(size_x, 2 * k_in * size_mem)(x)
r_non = cgt.reshape(r_vec, (size_batch, 2 * k_in, size_mem))
r_norm = cgt.norm(r_non, axis=2, keepdims=True)
r = cgt.broadcast('/', r_non, r_norm, "xxx,xx1")
prev_h_3 = cgt.reshape(prev_h, (size_batch, size_mem, 1))
inters_in = [prev_h_3]
colon = slice(None, None, None)
for i in xrange(2 * k_in):
inter_in = inters_in[-1]
r_cur = cgt.subtensor(r, [colon, i, colon])
r_cur_3_transpose = cgt.reshape(r_cur, (size_batch, 1, size_mem))
r_cur_3 = cgt.reshape(r_cur, (size_batch, size_mem, 1))
ref_cur = cgt.batched_matmul(r_cur_3, cgt.batched_matmul(r_cur_3_transpose, inter_in))
inter_out = inter_in - 2 * ref_cur
inters_in.append(inter_out)
h_in_rot = cgt.reshape(inters_in[-1], (size_batch, size_mem))
inters_h = [h_in_rot]
for i in xrange(2 * k_h):
inter_in = inters_h[-1]
r_cur = cgt.subtensor(xform_h, [i, colon])
r_cur_2_transpose = cgt.reshape(r_cur, (size_mem, 1))
r_cur_2 = cgt.reshape(r_cur, (1, size_mem))
ref_cur = cgt.dot(cgt.dot(inter_in, r_cur_2_transpose), r_cur_2)
inter_out = inter_in - 2 * ref_cur
inters_h.append(inter_out)
next_h = inters_h[-1]
outputs.append(next_h)
category_activations = nn.Affine(size_mem, size_output,name="pred")(outputs[-1])
logprobs = nn.logsoftmax(category_activations)
outputs.append(logprobs)
#print 'len outputs:', len(outputs)
#print 'len inputs:', len(inputs)
return nn.Module(inputs, outputs)
def flatcat(xs):
return cgt.concatenate([x.flatten() for x in xs])
def cat_sample(ps):
"""
sample from categorical distribution
ps is a 2D array whose rows are vectors of probabilities
"""
r = nr.rand(len(ps))
out = np.zeros(len(ps),dtype='i4')
cumsums = np.cumsum(ps, axis=1)
for (irow,csrow) in enumerate(cumsums):
for (icol, csel) in enumerate(csrow):
if csel > r[irow]:
out[irow] = icol
break
return out
def rmsprop_update(grad, state):
state.sqgrad[:] *= state.decay_rate
state.count *= state.decay_rate
np.square(grad, out=state.scratch) # scratch=g^2
state.sqgrad += state.scratch
state.count += 1
np.sqrt(state.sqgrad, out=state.scratch) # scratch = sum of squares
np.divide(state.scratch, np.sqrt(state.count), out=state.scratch) # scratch = rms
np.divide(grad, state.scratch, out=state.scratch) # scratch = grad/rms
np.multiply(state.scratch, state.step_size, out=state.scratch)
state.theta[:] -= state.scratch
def make_loss_and_grad_and_step(arch, size_input, size_output, size_mem, size_batch, n_layers, n_unroll, k_in, k_h):
# symbolic variables
x_tnk = cgt.tensor3()
targ_tnk = cgt.tensor3()
#make_network = make_deep_lstm if arch=="lstm" else make_deep_gru
make_network = make_deep_rrnn_rot_relu
network = make_network(size_input, size_mem, n_layers, size_output, size_batch, k_in, k_h)
init_hiddens = [cgt.matrix() for _ in xrange(get_num_hiddens(arch, n_layers))]
# TODO fixed sizes
cur_hiddens = init_hiddens
loss = 0
for t in xrange(n_unroll):
outputs = network([x_tnk[t]] + cur_hiddens)
cur_hiddens, prediction_logprobs = outputs[:-1], outputs[-1]
# loss = loss + nn.categorical_negloglik(prediction_probs, targ_tnk[t]).sum()
loss = loss - (prediction_logprobs*targ_tnk[t]).sum()
cur_hiddens = outputs[:-1]
final_hiddens = cur_hiddens
loss = loss / (n_unroll * size_batch)
params = network.get_parameters()
gradloss = cgt.grad(loss, params)
flatgrad = flatcat(gradloss)
with utils.Message("compiling loss+grad"):
f_loss_and_grad = cgt.function([x_tnk, targ_tnk] + init_hiddens, [loss, flatgrad] + final_hiddens)
f_loss = cgt.function([x_tnk, targ_tnk] + init_hiddens, loss)
assert len(init_hiddens) == len(final_hiddens)
x_nk = cgt.matrix('x')
outputs = network([x_nk] + init_hiddens)
f_step = cgt.function([x_nk]+init_hiddens, outputs)
# print "node count", cgt.count_nodes(flatgrad)
return network, f_loss, f_loss_and_grad, f_step
class Table(dict):
"dictionary-like object that exposes its keys as attributes"
def __init__(self, **kwargs):
dict.__init__(self, kwargs)
self.__dict__ = self
def make_rmsprop_state(theta, step_size, decay_rate):
return Table(theta=theta, sqgrad=np.zeros_like(theta)+1e-6, scratch=np.empty_like(theta),
step_size=step_size, decay_rate=decay_rate, count=0)
class Loader(object):
def __init__(self, data_dir, size_batch, n_unroll, split_fractions):
input_file = osp.join(data_dir,"input.txt")
preproc_file = osp.join(data_dir, "preproc.npz")
run_preproc = not osp.exists(preproc_file) or osp.getmtime(input_file) > osp.getmtime(preproc_file)
if run_preproc:
text_to_tensor(input_file, preproc_file)
data_file = np.load(preproc_file)
self.char2ind = {char:ind for (ind,char) in enumerate(data_file["chars"])}
data = data_file["inds"]
data = data[:data.shape[0] - (data.shape[0] % size_batch)].reshape(size_batch, -1).T # inds_tn
n_batches = (data.shape[0]-1) // n_unroll
data = data[:n_batches*n_unroll+1] # now t-1 is divisble by batch size
self.n_unroll = n_unroll
self.data = data
self.n_train_batches = int(n_batches*split_fractions[0])
self.n_test_batches = int(n_batches*split_fractions[1])
self.n_val_batches = n_batches - self.n_train_batches - self.n_test_batches
print "%i train batches, %i test batches, %i val batches"%(self.n_train_batches, self.n_test_batches, self.n_val_batches)
@property
def size_vocab(self):
return len(self.char2ind)
def train_batches_iter(self):
for i in xrange(self.n_train_batches):
start = i*self.n_unroll
stop = (i+1)*self.n_unroll
yield ind2onehot(self.data[start:stop], self.size_vocab), ind2onehot(self.data[start+1:stop+1], self.size_vocab) # XXX
# XXX move elsewhere
def ind2onehot(inds, n_cls):
inds = np.asarray(inds)
out = np.zeros(inds.shape+(n_cls,),cgt.floatX)
out.flat[np.arange(inds.size)*n_cls + inds.ravel()] = 1
return out
def text_to_tensor(text_file, preproc_file):
with open(text_file,"r") as fh:
text = fh.read()
char2ind = {}
inds = []
for char in text:
ind = char2ind.get(char, -1)
if ind == -1:
ind = len(char2ind)
char2ind[char] = ind
inds.append(ind)
np.savez(preproc_file, inds = inds, chars = sorted(char2ind, key = lambda char : char2ind[char]))
def get_num_hiddens(arch, n_layers):
return {"lstm" : 2 * n_layers, "gru" : n_layers}[arch]
def sample(f_step, init_hiddens, char2ind, n_steps, temp, seed_text = ""):
vocab_size = len(char2ind)
ind2char = {ind:char for (char,ind) in char2ind.iteritems()}
cur_hiddens = init_hiddens
t = StringIO()
t.write(seed_text)
for char in seed_text:
x_1k = ind2onehot([char2ind[char]], vocab_size)
net_outputs = f_step(x_1k, cur_hiddens)
cur_hiddens, logprobs_1k = net_outputs[:-1], net_outputs[-1]
if len(seed_text)==0:
logprobs_1k = np.zeros((1,vocab_size))
for _ in xrange(n_steps):
logprobs_1k /= temp
probs_1k = np.exp(logprobs_1k)
probs_1k /= probs_1k.sum()
index = cat_sample(probs_1k)[0]
char = ind2char[index]
x_1k = ind2onehot([index], vocab_size)
net_outputs = f_step(x_1k, *cur_hiddens)
cur_hiddens, logprobs_1k = net_outputs[:-1], net_outputs[-1]
t.write(char)
cgt.utils.colorprint(cgt.utils.Color.YELLOW, t.getvalue() + "\n")
def main():
nr.seed(0)
parser = argparse.ArgumentParser()
parser.add_argument("--data_dir", type=str, default="alice")
parser.add_argument("--size_mem", type=int,default=64)
parser.add_argument("--size_batch", type=int,default=64)
parser.add_argument("--n_layers",type=int,default=2)
parser.add_argument("--n_unroll",type=int,default=16)
parser.add_argument("--k_in",type=int,default=3)
parser.add_argument("--k_h",type=int,default=5)
parser.add_argument("--step_size",type=float,default=.01)
parser.add_argument("--decay_rate",type=float,default=0.95)
parser.add_argument("--n_epochs",type=int,default=20)
parser.add_argument("--arch",choices=["lstm","gru"],default="gru")
parser.add_argument("--grad_check",action="store_true")
parser.add_argument("--profile",action="store_true")
parser.add_argument("--unittest",action="store_true")
args = parser.parse_args()
cgt.set_precision("quad" if args.grad_check else "single")
assert args.n_unroll > 1
loader = Loader(args.data_dir,args.size_batch, args.n_unroll, (.8,.1,.1))
network, f_loss, f_loss_and_grad, f_step = make_loss_and_grad_and_step(args.arch, loader.size_vocab,
loader.size_vocab, args.size_mem, args.size_batch, args.n_layers, args.n_unroll, args.k_in, args.k_h)
if args.profile: profiler.start()
params = network.get_parameters()
pc = ParamCollection(params)
pc.set_value_flat(nr.uniform(-0.01, 0.01, size=(pc.get_total_size(),)))
for i, param in enumerate(pc.params):
if "is_rotation" in param.props:
shape = pc.get_shapes()[i]
num_vec = int(shape[0] / 2)
size_vec = int(shape[1])
gauss = nr.normal(size=(num_vec * size_vec))
gauss = np.reshape(gauss, (num_vec, size_vec))
gauss_mag = norm(gauss, axis=1, keepdims=True)
gauss_normed = gauss / gauss_mag
gauss_perturb = nr.normal(scale=0.01, size=(num_vec * size_vec))
gauss_perturb = np.reshape(gauss_perturb, (num_vec, size_vec))
second_vec = gauss_normed + gauss_perturb
second_vec_mag = norm(second_vec, axis=1, keepdims=True)
second_vec_normed = second_vec / second_vec_mag
new_param_value = np.zeros(shape)
for j in xrange(num_vec):
new_param_value[2 * j, :] = gauss_normed[j, :]
new_param_value[2 * j + 1, :] = second_vec_normed[j, :]
param.op.set_value(new_param_value)
#print new_param_value
def initialize_hiddens(n):
return [np.ones((n, args.size_mem), cgt.floatX) / float(args.size_mem) for _ in xrange(get_num_hiddens(args.arch, args.n_layers))]
if args.grad_check:
#if True:
x,y = loader.train_batches_iter().next()
prev_hiddens = initialize_hiddens(args.size_batch)
def f(thnew):
thold = pc.get_value_flat()
pc.set_value_flat(thnew)
loss = f_loss(x,y, *prev_hiddens)
pc.set_value_flat(thold)
return loss
from cgt.numeric_diff import numeric_grad
print "Beginning grad check"
g_num = numeric_grad(f, pc.get_value_flat(),eps=1e-10)
print "Ending grad check"
result = f_loss_and_grad(x,y,*prev_hiddens)
g_anal = result[1]
diff = g_num - g_anal
abs_diff = np.abs(diff)
print np.where(abs_diff > 1e-4)
print diff[np.where(abs_diff > 1e-4)]
embed()
assert np.allclose(g_num, g_anal, atol=1e-4)
print "Gradient check succeeded!"
return
optim_state = make_rmsprop_state(theta=pc.get_value_flat(), step_size = args.step_size,
decay_rate = args.decay_rate)
for iepoch in xrange(args.n_epochs):
losses = []
tstart = time()
print "starting epoch",iepoch
cur_hiddens = initialize_hiddens(args.size_batch)
for (x,y) in loader.train_batches_iter():
out = f_loss_and_grad(x,y, *cur_hiddens)
loss = out[0]
grad = out[1]
cur_hiddens = out[2:]
rmsprop_update(grad, optim_state)
pc.set_value_flat(optim_state.theta)
losses.append(loss)
if args.unittest: return
print "%.3f s/batch. avg loss = %.3f"%((time()-tstart)/len(losses), np.mean(losses))
optim_state.step_size *= .98 #pylint: disable=E1101
sample(f_step, initialize_hiddens(1), char2ind=loader.char2ind, n_steps=300, temp=1.0, seed_text = "")
if args.profile: profiler.print_stats()
if __name__ == "__main__":
main()