Error while training with Sequential in Keras: Shapes are incompatible - keras

I am training a neural network (2 conv layers and 1 dense hidden layer) to classify hand-sign images for 24 alphabets (J and Z has no images). Using ImageDataGenerator's flow() function to create training and testing data generators. Using Keras Sequential to create the neural network model. While training, I am getting the following error:
model = create_model()
# Train your model
history = model.fit(train_generator,
epochs=15,
validation_data=validation_generator)
Epoch 1/15
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-46-746fb7255d3f> in <module>()
6 history = model.fit(train_generator,
7 epochs=15,
----> 8 validation_data=validation_generator)
/usr/local/lib/python3.7/dist-packages/tensorflow/python/framework/func_graph.py in autograph_handler(*args, **kwargs)
1145 except Exception as e: # pylint:disable=broad-except
1146 if hasattr(e, "ag_error_metadata"):
-> 1147 raise e.ag_error_metadata.to_exception(e)
1148 else:
1149 raise
ValueError: in user code:
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 1021, in train_function *
return step_function(self, iterator)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 1010, in step_function **
outputs = model.distribute_strategy.run(run_step, args=(data,))
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 1000, in run_step **
outputs = model.train_step(data)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 860, in train_step
loss = self.compute_loss(x, y, y_pred, sample_weight)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 919, in compute_loss
y, y_pred, sample_weight, regularization_losses=self.losses)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/compile_utils.py", line 201, in __call__
loss_value = loss_obj(y_t, y_p, sample_weight=sw)
File "/usr/local/lib/python3.7/dist-packages/keras/losses.py", line 141, in __call__
losses = call_fn(y_true, y_pred)
File "/usr/local/lib/python3.7/dist-packages/keras/losses.py", line 245, in call **
return ag_fn(y_true, y_pred, **self._fn_kwargs)
File "/usr/local/lib/python3.7/dist-packages/keras/losses.py", line 1790, in categorical_crossentropy
y_true, y_pred, from_logits=from_logits, axis=axis)
File "/usr/local/lib/python3.7/dist-packages/keras/backend.py", line 5083, in categorical_crossentropy
target.shape.assert_is_compatible_with(output.shape)
**ValueError: Shapes (None, 1) and (None, 24) are incompatible**
Here is the link to the colab code: 1

You need to use one hot encoding for the y parameters where you define training and validation generator. So under 'train_val_generators' function change:
y=training_labels
into
y=tf.keras.utils.to_categorical(training_labels, x)
and do same thing for the validation. x is the number of output neurons.

Related

How to cascade two pretrained networks?

Very new to deep learning, I was researching into cascading multiple neural networks and was wondering how to actually put it into code. For a lesser example, say I imported a vgg and resnet model trained on imagenet. Is there an easy way to do this?
I have tried playing around with it and concatenating the outputs of 3 of these networks, putting them in a dense layer, and completing the model. But, I'm being thrown a error.
model1 = load_model(save_path1)
model2 = load_model(save_path2)
model1_out = model1.output
model2_out = model2.output
concat = tf.keras.layers.Concatenate()([model1_out, model2_out])
concatout = Dense(10, activation='softmax')(concat)
combined = models.Model(inputs=[model1.input, model2.input], outputs=[concatout])
combined.compile(optimizer='adam',
loss="categorical_crossentropy",
metrics=['accuracy'])
test_scores = combined.evaluate(x_test, y_test, verbose=2)
print('Loss for test dataset:', test_scores[0])
print('Accuracy for test dataset:', test_scores[1])
test_scores = combined.evaluate(x_test, y_test, verbose=2)
print('Loss for test dataset:', test_scores[0])
print('Accuracy for test dataset:', test_scores[1])
Error: File
ile "C:\\pythonProject1\backup.py", line 72, in <module>
test_scores = combined.evaluate(x_test, y_test, verbose=2)
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\utils\traceback_utils.py", line 67, in error_handler
raise e.with_traceback(filtered_tb) from None
File "C:\Users\\AppData\Local\Temp\__autograph_generated_file1poeqzyb.py", line 15, in tf__test_function
retval_ = ag__.converted_call(ag__.ld(step_function), (ag__.ld(self), ag__.ld(iterator)), None, fscope)
ValueError: in user code:
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\engine\training.py", line 1557, in test_function *
return step_function(self, iterator)
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\engine\training.py", line 1546, in step_function **
outputs = model.distribute_strategy.run(run_step, args=(data,))
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\engine\training.py", line 1535, in run_step **
outputs = model.test_step(data)
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\engine\training.py", line 1499, in test_step
y_pred = self(x, training=False)
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\utils\traceback_utils.py", line 67, in error_handler
raise e.with_traceback(filtered_tb) from None
File "C:\Users\\miniconda3\envs\tf1\lib\site-packages\keras\engine\input_spec.py", line 200, in assert_input_compatibility
raise ValueError(f'Layer "{layer_name}" expects {len(input_spec)} input(s),'
ValueError: Layer "model" expects 2 input(s), but it received 1 input tensors. Inputs received: [<tf.Tensor 'IteratorGetNext:0' shape=(None, 48, 48, 3) dtype=float32>]

ValueError: `logits` and `labels` must have the same shape, received ((None, 1, 1, 10) vs (None, None))

im trying to re train the mobilnet model with my own dataset and when I am trying to fit the model I get these error.
mobile=tf.keras.applications.mobilenet.MobileNet()
x=mobile.layers[-5].output
output=Dense(units=10, activation='sigmoid')(x)
model=Model(inputs=mobile.input, outputs=output)
for layer in model.layers[:-23]:
layer.trainable=False
model.compile(optimizer=Adam(learning_rate=0.0001),loss='binary_crossentropy', metrics= ['accuracy'])
model.fit(
x=train_gen,
validation_data=valid_gen,
epochs=10)
ValueError: in user code:
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 1021, in train_function *
return step_function(self, iterator)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 1010, in step_function **
outputs = model.distribute_strategy.run(run_step, args=(data,))
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 1000, in run_step **
outputs = model.train_step(data)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 860, in train_step
loss = self.compute_loss(x, y, y_pred, sample_weight)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/training.py", line 919, in compute_loss
y, y_pred, sample_weight, regularization_losses=self.losses)
File "/usr/local/lib/python3.7/dist-packages/keras/engine/compile_utils.py", line 201, in __call__
loss_value = loss_obj(y_t, y_p, sample_weight=sw)
File "/usr/local/lib/python3.7/dist-packages/keras/losses.py", line 141, in __call__
losses = call_fn(y_true, y_pred)
File "/usr/local/lib/python3.7/dist-packages/keras/losses.py", line 245, in call **
return ag_fn(y_true, y_pred, **self._fn_kwargs)
File "/usr/local/lib/python3.7/dist-packages/keras/losses.py", line 1932, in binary_crossentropy
backend.binary_crossentropy(y_true, y_pred, from_logits=from_logits),
File "/usr/local/lib/python3.7/dist-packages/keras/backend.py", line 5247, in binary_crossentropy
return tf.nn.sigmoid_cross_entropy_with_logits(labels=target, logits=output)
ValueError: `logits` and `labels` must have the same shape, received ((None, 1, 1, 10) vs (None, None)).

Using albumentation with Tensorflow Sequence API

I am trying to use tf.keras.utils.Sequence object as input to my keras model so,that I can apply augmentations that are not available in tensorflow using albumentations library. But I am getting error while doing so. (The image pre-processing operations mentioned here are just for clarity)
import albumentations as A
from tensorflow.keras.utils import Sequence
import os
import glob
import numpy as np
import matplotlib.pyplot as plt
from tensorflow.keras.layers import Dense, Conv2D, Flatten, MaxPool2D, Dropout
from tensorflow.keras.models import Sequential
TRAIN_DIR = os.path.join('..', 'Data', 'PetImages')
def load_data():
list_of_fpaths = glob.glob('../Data/PetImages/Cat/*')
labels = [1] * len(list_of_fpaths)
temp = glob.glob('../Data/PetImages/Dog/*')
list_of_fpaths.extend(temp)
labels.extend([0] * len(temp))
return list_of_fpaths, labels
# Now list of fpaths contain the list of file paths and labels contain
# corresponding labels
class DataSequence(Sequence):
def __init__(self, x_set, y_set, batch_size, augmentations):
self.x, self.y = x_set, y_set
self.batch_size = batch_size
self.augment = augmentations
def __len__(self):
return int(np.ceil(len(self.x) / float(self.batch_size)))
def __getitem__(self, idx):
batch_x = self.x[idx * self.batch_size:(idx + 1) * self.batch_size]
batch_y = self.y[idx * self.batch_size:(idx + 1) * self.batch_size]
a = np.array([
self.augment(image=plt.imread(file_name))["image"] for file_name in
batch_x
])
b = np.array(batch_y)
return a,b
def get_model(input_shape):
model = Sequential([
Conv2D(8, 3, activation='relu', input_shape=input_shape),
MaxPool2D(2),
Conv2D(16, 3, activation='relu'),
MaxPool2D(2),
Conv2D(32, 3, activation='relu'),
MaxPool2D(2),
Conv2D(32, 3, activation='relu'),
MaxPool2D(2),
Conv2D(32, 3, activation='relu'),
MaxPool2D(2),
Flatten(),
Dense(1024, activation='relu'),
Dropout(0.3),
Dense(1, activation='sigmoid')
])
model.compile(optimizer='adam',
loss='binary_crossentropy',
metrics=['accuracy']
)
return model
ALBUMENTATIONS_TRAIN = A.Compose([
A.Resize(256, 256),
# A.Resize(512, 512),
A.ToFloat(),
# A.RandomCrop(384, 384, p=0.5),
])
ALBUMENTATIONS_TEST = A.Compose([
A.ToFloat(),
A.Resize(256, 256)
])
X, Y = load_data()
train_gen = DataSequence(X, Y, 16, ALBUMENTATIONS_TRAIN)
model = get_model(input_shape=(256,256,3))
model.fit(train_gen,epochs=100)
The error that I am getting is
17/748 [..............................] - ETA: 1:06 - loss: 0.4304 - accuracy: 0.92282020-07-08 13:25:47.751964: W tensorflow/core/framework/op_kernel.cc:1741] Invalid argument: ValueError: could not broadcast input array from shape (256,256,3) into shape (256,256)
Traceback (most recent call last):
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\ops\script_ops.py", line 243, in __call__
ret = func(*args)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\autograph\impl\api.py", line 309, in wrapper
return func(*args, **kwargs)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\data\ops\dataset_ops.py", line 785, in generator_py_func
values = next(generator_state.get_iterator(iterator_id))
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\data_adapter.py", line 801, in wrapped_generator
for data in generator_fn():
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\data_adapter.py", line 932, in generator_fn
yield x[i]
File "D:/ACAD/TENSORFLOW/Rough/data_aug_pipeline.py", line 40, in __getitem__
a = np.array([
ValueError: could not broadcast input array from shape (256,256,3) into shape (256,256)
Traceback (most recent call last):
File "D:/ACAD/TENSORFLOW/Rough/data_aug_pipeline.py", line 89, in <module>
model.fit(train_gen,epochs=100)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\training.py", line 66, in _method_wrapper
return method(self, *args, **kwargs)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\training.py", line 848, in fit
tmp_logs = train_function(iterator)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\def_function.py", line 580, in __call__
result = self._call(*args, **kwds)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\def_function.py", line 611, in _call
return self._stateless_fn(*args, **kwds) # pylint: disable=not-callable
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\function.py", line 2420, in __call__
return graph_function._filtered_call(args, kwargs) # pylint: disable=protected-access
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\function.py", line 1661, in _filtered_call
return self._call_flat(
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\function.py", line 1745, in _call_flat
return self._build_call_outputs(self._inference_function.call(
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\function.py", line 593, in call
outputs = execute.execute(
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\eager\execute.py", line 59, in quick_execute
tensors = pywrap_tfe.TFE_Py_Execute(ctx._handle, device_name, op_name,
tensorflow.python.framework.errors_impl.InvalidArgumentError: 2 root error(s) found.
(0) Invalid argument: ValueError: could not broadcast input array from shape (256,256,3) into shape (256,256)
Traceback (most recent call last):
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\ops\script_ops.py", line 243, in __call__
ret = func(*args)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\autograph\impl\api.py", line 309, in wrapper
return func(*args, **kwargs)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\data\ops\dataset_ops.py", line 785, in generator_py_func
values = next(generator_state.get_iterator(iterator_id))
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\data_adapter.py", line 801, in wrapped_generator
for data in generator_fn():
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\data_adapter.py", line 932, in generator_fn
yield x[i]
File "D:/ACAD/TENSORFLOW/Rough/data_aug_pipeline.py", line 40, in __getitem__
a = np.array([
ValueError: could not broadcast input array from shape (256,256,3) into shape (256,256)
[[{{node PyFunc}}]]
[[IteratorGetNext]]
[[IteratorGetNext/_4]]
(1) Invalid argument: ValueError: could not broadcast input array from shape (256,256,3) into shape (256,256)
Traceback (most recent call last):
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\ops\script_ops.py", line 243, in __call__
ret = func(*args)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\autograph\impl\api.py", line 309, in wrapper
return func(*args, **kwargs)
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\data\ops\dataset_ops.py", line 785, in generator_py_func
values = next(generator_state.get_iterator(iterator_id))
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\data_adapter.py", line 801, in wrapped_generator
for data in generator_fn():
File "C:\Users\aksha\Anaconda3\envs\tf\lib\site-packages\tensorflow\python\keras\engine\data_adapter.py", line 932, in generator_fn
yield x[i]
File "D:/ACAD/TENSORFLOW/Rough/data_aug_pipeline.py", line 40, in __getitem__
a = np.array([
ValueError: could not broadcast input array from shape (256,256,3) into shape (256,256)
[[{{node PyFunc}}]]
[[IteratorGetNext]]
0 successful operations.
0 derived errors ignored. [Op:__inference_train_function_1195]
Function call stack:
train_function -> train_function
Process finished with exit code 1
Please help me to understand what mistake I am making.
Base on the error messages, there is at least one grayscale image in your dataset that was resize to 256x256 and thus cannot fit into your network.

Evaluating pairwise distances between the output of a tf.keras.model

I am trying to create a custom loss function in tensorflow. I am using tensorflow v2.0.rc0 for running the code. Following is the code and the function min_dist_loss computes the pairwise loss between the output of the neural network. Here's the code
def min_dist_loss(_, y_pred):
distances = []
for i in range(0, 16):
for j in range(i + 1, 16):
distances.append(tf.linalg.norm(y_pred[i] - y_pred[j]))
return -tf.reduce_min(distances)
and the module is being initialized and compiled as follows
import tensorflow as tf
from tensorboard.plugins.hparams import api as hp
HP_NUM_UNITS = hp.HParam('num_units', hp.Discrete([6, 7]))
HP_OPTIMIZER = hp.HParam('optimizer', hp.Discrete(['adam', 'sgd']))
METRIC_ACCURACY = 'accuracy'
with tf.summary.create_file_writer('logs\hparam_tuning').as_default():
hp.hparams_config(
hparams=[HP_NUM_UNITS, HP_OPTIMIZER],
metrics=[hp.Metric(METRIC_ACCURACY, display_name='Accuracy')]
)
def train_test_model(logdir, hparams):
weight1 = np.random.normal(loc=0.0, scale=0.01, size=[4, hparams[HP_NUM_UNITS]])
init1 = tf.constant_initializer(weight1)
weight2 = np.random.normal(loc=0.0, scale=0.01, size=[hparams[HP_NUM_UNITS], 7])
init2 = tf.constant_initializer(weight2)
model = tf.keras.models.Sequential([
# tf.keras.layers.Flatten(),
tf.keras.layers.Dense(hparams[HP_NUM_UNITS], activation=tf.nn.sigmoid, kernel_initializer=init1),
tf.keras.layers.Dense(7, activation=tf.nn.sigmoid, kernel_initializer=init2) if hparams[HP_NUM_UNITS] == 6 else
None,
])
model.compile(
optimizer=hparams[HP_OPTIMIZER],
loss=min_dist_loss,
# metrics=['accuracy'],
)
x_train = [list(k) for k in itertools.product([0, 1], repeat=4)]
shuffle(x_train)
x_train = 2 * np.array(x_train) - 1
model.fit(
x_train, epochs=1, batch_size=16,
callbacks=[
tf.keras.callbacks.TensorBoard(logdir),
hp.KerasCallback(logdir, hparams)
],
)
Now since the tensor object y_pred in the min_dist_loss is an object of shape [?, 7], indexing with i is throwing the following error:
Traceback (most recent call last):
File "/home/pc/Documents/user/code/keras_tensorflow/src/try1.py", line 95, in <module>
run('logs\hparam_tuning' + run_name, hparams)
File "/home/pc/Documents/user/code/keras_tensorflow/src/try1.py", line 78, in run
accuracy = train_test_model(run_dir, hparams)
File "/home/pc/Documents/user/code/keras_tensorflow/src/try1.py", line 66, in train_test_model
hp.KerasCallback(logdir, hparams)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training.py", line 734, in fit
use_multiprocessing=use_multiprocessing)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_v2.py", line 324, in fit
total_epochs=epochs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_v2.py", line 123, in run_one_epoch
batch_outs = execution_function(iterator)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 86, in execution_function
distributed_function(input_fn))
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/eager/def_function.py", line 427, in __call__
self._initialize(args, kwds, add_initializers_to=initializer_map)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/eager/def_function.py", line 370, in _initialize
*args, **kwds))
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/eager/function.py", line 1847, in _get_concrete_function_internal_garbage_collected
graph_function, _, _ = self._maybe_define_function(args, kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/eager/function.py", line 2147, in _maybe_define_function
graph_function = self._create_graph_function(args, kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/eager/function.py", line 2038, in _create_graph_function
capture_by_value=self._capture_by_value),
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/framework/func_graph.py", line 915, in func_graph_from_py_func
func_outputs = python_func(*func_args, **func_kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/eager/def_function.py", line 320, in wrapped_fn
return weak_wrapped_fn().__wrapped__(*args, **kwds)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 73, in distributed_function
per_replica_function, args=(model, x, y, sample_weights))
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/distribute/distribute_lib.py", line 760, in experimental_run_v2
return self._extended.call_for_each_replica(fn, args=args, kwargs=kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/distribute/distribute_lib.py", line 1787, in call_for_each_replica
return self._call_for_each_replica(fn, args, kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/distribute/distribute_lib.py", line 2132, in _call_for_each_replica
return fn(*args, **kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/autograph/impl/api.py", line 292, in wrapper
return func(*args, **kwargs)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_v2_utils.py", line 264, in train_on_batch
output_loss_metrics=model._output_loss_metrics)
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_eager.py", line 311, in train_on_batch
output_loss_metrics=output_loss_metrics))
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_eager.py", line 252, in _process_single_batch
training=training))
File "/home/pc/Documents/user/code/keras_tensorflow/venv/lib/python3.6/site-packages/tensorflow_core/python/keras/engine/training_eager.py", line 166, in _model_loss
per_sample_losses = loss_fn.call(targets[i], outs[i])
IndexError: list index out of range
How do I compute the minimum distance in this setting? Any help is appreciated. Also, if there are any errors in other parts of the code, please feel free to point it out. I am new to using keras on tensorflow.
Keras is expecting you to provide the true labels as well. Since you're defining your own loss function and you're not using the true labels, you can pass some garbage labels. Eg: np.arange(16).
Change your model.fit as below and it should work
model.fit(
x_train, np.arange(x_train.shape[0]), epochs=1, batch_size=16,
callbacks=[
tf.keras.callbacks.TensorBoard(logdir),
hp.KerasCallback(logdir, hparams)
],
)

Keras int_shape returns None in custom loss function

My try to obtain the batch size within a custom loss function using K.int_shape() demonstrated by the code below.
from keras import layers, Input, Model
import keras.backend as K
import numpy as np
train_X=np.random.random([100, 5])
train_Y=train_X.sum(axis=1)
inputs=Input(shape=(5,), dtype='float32', name='posts')
outputs=layers.Dense(1, activation='relu')(inputs)
model = Model(inputs, outputs)#, net_qc])
model.summary()
def myloss(y_true, y_pred):
n=K.int_shape(y_pred)[0]
return K.sum(y_pred)/n
model.compile(optimizer='adam', loss=myloss)
model.fit(train_X, train_Y, epochs=10, batch_size=10)
The error message below suggest K.int_shape returns None. I have tried several things without success, would really appreciate some helps.
Traceback (most recent call last):
File "./test_intshape.py", line 21, in <module>
model.compile(optimizer='adam', loss=myloss)
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/keras/engine/training.py", line 830, in compile
sample_weight, mask)
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/keras/engine/training.py", line 429, in weighted
score_array = fn(y_true, y_pred)
File "./test_intshape.py", line 19, in myloss
return K.sum(y_pred)/n
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/tensorflow/python/ops/math_ops.py", line 820, in binary_op_wrapper
y = ops.convert_to_tensor(y, dtype=x.dtype.base_dtype, name="y")
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 639, in convert_to_tensor
as_ref=False)
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 704, in internal_convert_to_tensor
ret = conversion_func(value, dtype=dtype, name=name, as_ref=as_ref)
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/tensorflow/python/framework/constant_op.py", line 113, in _constant_tensor_conversion_function
return constant(v, dtype=dtype, name=name)
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/tensorflow/python/framework/constant_op.py", line 102, in constant
tensor_util.make_tensor_proto(value, dtype=dtype, shape=shape, verify_shape=verify_shape))
File "/home/ubuntu/anaconda3/envs/tensorflow_p36/lib/python3.6/site-packages/tensorflow/python/framework/tensor_util.py", line 360, in make_tensor_proto
raise ValueError("None values not supported.")
ValueError: None values not supported.
That is the expected behaviour because K.int_shape() doesn't return a symbolic tensor but the current known shape. Well you would only know the batch size at runtime and when constructing the graph it will be None. What you are looking for is K.shape() instead which will return the symbolic tensor that will have the batch size set at runtime, ie:
n = K.shape(y_pred)[0]

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