I got the following error when I try to run the code at the end of the post. But it is not clear to me what is wrong with my code. Could anybody let me know the tricks in debugging a tensorflow program?
$ ./main.py
Extracting /tmp/data/train-images-idx3-ubyte.gz
Extracting /tmp/data/train-labels-idx1-ubyte.gz
Extracting /tmp/data/t10k-images-idx3-ubyte.gz
Extracting /tmp/data/t10k-labels-idx1-ubyte.gz
2017-12-11 22:53:16.061163: I tensorflow/core/platform/cpu_feature_guard.cc:137] Your CPU supports instructions that this TensorFlow binary was not compiled to use: SSE4.1 SSE4.2 AVX AVX2 FMA
Traceback (most recent call last):
File "./main.py", line 55, in <module>
sess.run(opt, feed_dict={x: batch_x, y: batch_y})
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 889, in run
run_metadata_ptr)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1120, in _run
feed_dict_tensor, options, run_metadata)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1317, in _do_run
options, run_metadata)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1336, in _do_call
raise type(e)(node_def, op, message)
tensorflow.python.framework.errors_impl.FailedPreconditionError: Attempting to use uninitialized value beta1_power
[[Node: beta1_power/read = Identity[T=DT_FLOAT, _class=["loc:@Variable"], _device="/job:localhost/replica:0/task:0/device:CPU:0"](beta1_power)]]
Caused by op u'beta1_power/read', defined at:
File "./main.py", line 46, in <module>
opt=tf.train.AdamOptimizer(learning_rate=learning_rate).minimize(loss)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/training/optimizer.py", line 353, in minimize
name=name)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/training/optimizer.py", line 474, in apply_gradients
self._create_slots([_get_variable_for(v) for v in var_list])
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/training/adam.py", line 130, in _create_slots
trainable=False)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/ops/variable_scope.py", line 1927, in variable
caching_device=caching_device, name=name, dtype=dtype)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/ops/variables.py", line 213, in __init__
constraint=constraint)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/ops/variables.py", line 356, in _init_from_args
self._snapshot = array_ops.identity(self._variable, name="read")
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/ops/array_ops.py", line 125, in identity
return gen_array_ops.identity(input, name=name)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/ops/gen_array_ops.py", line 2071, in identity
"Identity", input=input, name=name)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/framework/op_def_library.py", line 787, in _apply_op_helper
op_def=op_def)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 2956, in create_op
op_def=op_def)
File "/usr/local/lib/python2.7/site-packages/tensorflow/python/framework/ops.py", line 1470, in __init__
self._traceback = self._graph._extract_stack() # pylint: disable=protected-access
FailedPreconditionError (see above for traceback): Attempting to use uninitialized value beta1_power
[[Node: beta1_power/read = Identity[T=DT_FLOAT, _class=["loc:@Variable"], _device="/job:localhost/replica:0/task:0/device:CPU:0"](beta1_power)]]
The code is here. It uses LSTM.
#!/usr/bin/env python
# vim: set noexpandtab tabstop=2 shiftwidth=2 softtabstop=-1 fileencoding=utf-8:
import tensorflow as tf
from tensorflow.contrib import rnn
#import mnist dataset
from tensorflow.examples.tutorials.mnist import input_data
mnist=input_data.read_data_sets("/tmp/data/", one_hot=True)
learning_rate=0.001
#defining placeholders
#input image placeholder
time_steps=28
n_input=28
x=tf.placeholder("float", [None, time_steps, n_input])
#processing the input tensor from [batch_size,n_steps,n_input] to "time_steps" number of [batch_size,n_input] tensors
input=tf.unstack(x, time_steps, 1)
#defining the network
num_units=128
lstm_layer = rnn.BasicLSTMCell(num_units, forget_bias=1)
outputs,_ = rnn.static_rnn(lstm_layer, input, dtype="float32")
#weights and biases of appropriate shape to accomplish above task
n_classes=10
out_weights=tf.Variable(tf.random_normal([num_units, n_classes]))
out_bias=tf.Variable(tf.random_normal([n_classes]))
#converting last output of dimension [batch_size,num_units] to [batch_size,n_classes] by out_weight multiplication
prediction=tf.matmul(outputs[-1], out_weights) + out_bias
y=tf.placeholder("float", [None, n_classes])
loss=tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(logits=prediction, labels=y))
#optimization
#model evaluation
correct_prediction=tf.equal(tf.argmax(prediction, 1), tf.argmax(y, 1))
accuracy=tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
#initialize variables
init=tf.global_variables_initializer()
batch_size=128
opt=tf.train.AdamOptimizer(learning_rate=learning_rate).minimize(loss)
with tf.Session() as sess:
sess.run(init)
iter=1
while iter<800:
batch_x, batch_y = mnist.train.next_batch(batch_size=batch_size)
batch_x=batch_x.reshape((batch_size, time_steps, n_input))
sess.run(opt, feed_dict={x: batch_x, y: batch_y})
if iter %10==0:
acc=sess.run(accuracy,feed_dict={x:batch_x,y:batch_y})
los=sess.run(loss,feed_dict={x:batch_x,y:batch_y})
print("For iter ",iter)
print("Accuracy ",acc)
print("Loss ",los)
print("__________________")
iter=iter+1
#calculating test accuracy
test_data = mnist.test.images[:128].reshape((-1, time_steps, n_input))
test_label = mnist.test.labels[:128]
print("Testing Accuracy:", sess.run(accuracy, feed_dict={x: test_data, y: test_label}))
Change the order of these two lines:
opt=tf.train.AdamOptimizer(learning_rate=learning_rate).minimize(loss)
init=tf.global_variables_initializer()
Since AdamOptimizer
has it's own variables, you should define the initilizer init
after opt
, not before.