This is probably a very simple question, however I am fairly new to tensorflow and have been stuck at this issue. I use tensorflow 1.12 and python 3.
My question is, what is the proper way to set the shape of a tensor object that is returned by the iterator?
With placeholders I can make make something like this code work, but I would like to make this work without a placeholder and using tensorflow datasets.
I cannot figure out how to align the shape of a tensor with a matrix in order to use tf.matmul.
The error I receive is: ValueError: Shape must be rank 2 but is rank 1 for 'MatMul_19' (op: 'MatMul') with input shapes: [2], [2,1].
The dataset of the iterator is specified as: TensorSliceDataset shapes: (2,), types: tf.float32>.
Thanks in advance!
import tensorflow as tf
import numpy as np
batch_size = 200
# this simulates a dataset read from a csv.....
x=np.array([[0., 0.], [1., 0.], [0., 1.], [1., 1.]],dtype="float32")
y=np.array([0, 0, 0, 1],dtype="float32")
dataset = tf.data.Dataset.from_tensor_slices((x))
print(dataset) # <TensorSliceDataset shapes: (2,), types: tf.float32>
dataset = dataset.repeat(10000)
print('repeat ds ', dataset) # repeat ds <RepeatDataset shapes: (2,), types: tf.float32>
iter = dataset.make_initializable_iterator()
print('iterator ', iter) # iterator <tensorflow.python.data.ops.iterator_ops.Iterator object at 0x0000028589C62550>
sess = tf.Session()
sess.run(iter.initializer)
next_elt= iter.get_next()
print('shape of dataset ', dataset , '[iterator] elt ', next_elt) # shape of dataset <RepeatDataset shapes: (2,), types: tf.float32> [iterator] elt Tensor("IteratorGetNext_105:0", shape=(2,), dtype=float32)
print('shape of it ', next_elt.shape) #s hape of it (2,)
for i in range(4):
print(sess.run(next_elt))
''' outputs:
[0. 0.]
[1. 0.]
[0. 1.]
[1. 1.]
'''
w = tf.Variable(tf.random_uniform([2,1], -1, 1, seed = 1234),name="weights_layer_1")
# this is where the error is because of shape mismatch of iterator and w variable.
# How od I make the shape of the iterator (2,1) so that matmul can be used?
# What is the proper way of aligning a tensor shape with inut data
# The output of the error:
# ValueError: Shape must be rank 2 but is rank 1 for 'MatMul_19' (op: 'MatMul') with input shapes: [2], [2,1].
H = tf.matmul( sess.run(next_elt) , w)
