I'm trying to feed TensorFlow dataset (which is read from .csv files) into multi-input tf.keras model defined with functional API. Training works fine when I pass these datasets zipped together with labels. When I want to call predict() (presumably on some different dataset that is not labelled) it throws an error (both in eager and non-eager execution)
Here's my current code:
import tensorflow as tf
import numpy as np
tf.enable_eager_execution()
# Define model.
input_A = tf.keras.layers.Input(shape=(None, 5), name='sensor_A_input')
x_1 = tf.keras.layers.LSTM(5, return_sequences=False, recurrent_initializer='glorot_uniform')(input_A)
input_B = tf.keras.layers.Input(shape=(None, 4), name='sensor_B_input')
x_2 = tf.keras.layers.LSTM(5, return_sequences=False, recurrent_initializer='glorot_uniform')(input_B)
x = tf.keras.layers.concatenate([x_1, x_2], name='concat_test')
output = tf.keras.layers.Dense(1, activation='sigmoid', name='output')(x)
model = tf.keras.Model(inputs=[input_A, input_B], outputs=output)
model.compile(optimizer='rmsprop',
loss='categorical_crossentropy',
metrics=['accuracy'])
model.run_eagerly = tf.executing_eagerly()
# Define input data.
# Dataset 1 is read from 10 .csv files where one file is one timeseries observation sequence of length 100 and 5 dimensions.
dataset_1 = tf.data.Dataset.from_tensor_slices(np.random.rand(10, 100, 5))
# Dataset 2 is read from 10 .csv files where one file is one timeseries observation sequence of length 300 and 4 dimensions.
dataset_2 = tf.data.Dataset.from_tensor_slices(np.random.rand(10, 300, 4))
# Define labels.
labels = tf.data.Dataset.from_tensor_slices(np.random.randint(0, 2, (10, 1)))
# Zip inputs and output into one dataset.
input_with_labels = tf.data.Dataset.zip(((dataset_1, dataset_2), labels)).batch(10)
model.fit(input_with_labels)
# Here's the problem - how should the input be arranged?
zipped_input = tf.data.Dataset.zip((dataset_1, dataset_2)).batch(10)
predictions = model.predict_generator(zipped_input)
print(predictions)
Here's the error:
ValueError: Error when checking model input: the list of Numpy arrays that you are passing to your model is not the size the model expected. Expected to see 2 array(s), but instead got the following list of 1 arrays: [<tf.Tensor: id=71049, shape=(10, 100, 5), dtype=float64, numpy=
array([[[0.54049765, 0.64218937, 0.31734092, 0.81307839, 0.75465237],
[0.32371089, 0.85923477, 0.60619924, 0.68692891, 0.186234...
Full traceback:
Traceback (most recent call last):
File "C:/xxx/debug_multiple_input_model.py", line 39, in <module>
model.predict(zipped_input)
File "C:\env_path\lib\site-packages\tensorflow\python\keras\engine\training.py", line 1054, in predict
callbacks=callbacks)
File "C:\env_path\lib\site-packages\tensorflow\python\keras\engine\training_generator.py", line 264, in model_iteration
batch_outs = batch_function(*batch_data)
File "C:\env_path\lib\site-packages\tensorflow\python\keras\engine\training_generator.py", line 536, in predict_on_batch
return model.predict_on_batch(x)
File "C:\env_path\lib\site-packages\tensorflow\python\keras\engine\training.py", line 1281, in predict_on_batch
x, extract_tensors_from_dataset=True)
File "C:\env_path\lib\site-packages\tensorflow\python\keras\engine\training.py", line 2651, in _standardize_user_data
exception_prefix='input')
File "C:\env_path\lib\site-packages\tensorflow\python\keras\engine\training_utils.py", line 346, in standardize_input_data
str(len(data)) + ' arrays: ' + str(data)[:200] + '...')
ValueError: Error when checking model input: the list of Numpy arrays that you are passing to your model is not the size the model expected. Expected to see 2 array(s), but instead got the following list of 1 arrays: [<tf.Tensor: id=71049, shape=(10, 100, 5), dtype=float64, numpy=
array([[[0.54049765, 0.64218937, 0.31734092, 0.81307839, 0.75465237],
[0.32371089, 0.85923477, 0.60619924, 0.68692891, 0.186234...
I've also tried calling predict() function like this:
1:
model.predict_generator(zipped_input)
results in the same error.
2:
model.predict((dataset_1, dataset_2))
throws this error:
AttributeError: 'DatasetV1Adapter' object has no attribute 'shape'
It turned out that a 1-element tuple should be given as the input to tf.data.Dataset.zip() function:
zipped_input = tf.data.Dataset.zip(((dataset_1, dataset_2), )).batch(10)
This produces an expected result.