ValueError: If printing histograms, validation_data must be provided, and cannot be a generator.

[xiaofengqing]

After i trained the first epoch，i meet this error
File "/home/s405/pengcheng/project/Keras-FCN/train.py", line 232, in
label_suffix=label_suffix, ignore_label=ignore_label, label_cval=label_cval)
File "/home/s405/pengcheng/project/Keras-FCN/train.py", line 164, in train
class_weight=class_weight
File "/usr/local/lib/python3.4/dist-packages/keras/legacy/interfaces.py", line 87, in wrapper
return func(*args, **kwargs)
File "/usr/local/lib/python3.4/dist-packages/keras/engine/training.py", line 2082, in fit_generator
callbacks.on_epoch_end(epoch, epoch_logs)
File "/usr/local/lib/python3.4/dist-packages/keras/callbacks.py", line 77, in on_epoch_end
callback.on_epoch_end(epoch, logs)
File "/usr/local/lib/python3.4/dist-packages/keras/callbacks.py", line 751, in on_epoch_end
raise ValueError('If printing histograms, validation_data must be '
ValueError: If printing histograms, validation_data must be provided, and cannot be a generator.

I don't know how to fix this problem, can you give me some suggestions?

[zwlshine]

I have also meet this error and I could not solve it yet ! Need help also！

[zwlshine]

@xiaofengqing Comment out this code: # if K.backend() == 'tensorflow':
# tensorboard = TensorBoard(log_dir=os.path.join(save_path, 'logs'), histogram_freq=10, write_graph=True)
# callbacks.append(tensorboard)

Then it can run.

[IsaacTegeler]

Change histogram_freq=10 to histogram_freq=0 you can still use tensor board with this fix rather than removing it all together.

[peachthiefmedia]

It is general issue with keras/tboard that you cannot get histograms with a validation_generator, changing histogram_freq=0 stops it trying to produce them.

[NoushNabi]

@zwlshine
I tried following lines and did not work for me.
if K.backend() == 'tensorflow':
tensorboard = TensorBoard(log_dir=os.path.join(save_path, 'logs'), histogram_freq=10, write_graph=True)
callbacks.append(tensorboard)

@IsaacIsOkay
When I turned histogram_freq to zero, it worked.

[mueller91]

How is turning histogram_freq to zero a fix?! I need those histograms.

[peachthiefmedia]

@mueller91 you can pass validation data separately to generate the histograms I think in a separate step, but yeah it isn't whats needed really.

[MaximilianPavon]

@mueller91 I am not sure if you still have this issue, but this issue keras-team/keras#3358 and the suggested solution by juiceboxjoe helped me.

[lucy9410]

Change histogram_freq=10 to histogram_freq=0 you can still use tensor board with this fix rather than removing it all together.

the original callbacks.py is with histogram_freq=0, but i still have ValueError: If printing histograms, validation_data must be provided, and cannot be a generator.

[guysoft]

Is there a method from a validation generator, that would just spit out a bunch of them to test with?
something along the line of get_validation(validation_generator) that would return what we need to add there?

[WittmannF]

It is general issue with keras/tboard that you cannot get histograms with a validation_generator, changing histogram_freq=0 stops it trying to produce them.

What's the issue? Why it is not possible when the validation set is a generator?