I want to customise the last layer of VGG 19 architecture for a classification. which will be more useful keras or pytorch?
I want to customise the last layer of VGG 19 architecture for a classification problem. which will be more useful keras or pytorch?

It heavily depends on what you want to do with it.
While Keras offers different backends, such as TensorFlow or Theano (which in turn can offer you a little more flexibility), and transfers better to production systems,
PyTorch is definitely also easy to implement. Additionally, it offers great scaling on (multi-)GPU systems, since it is trivial to outsource your computations in a PyTorch model. I do not know how easy that is in Keras (never done it, so I genuinely cannot judge).

If you just want to play around with one of the frameworks, it usually boils down to personal preference. I personally prefer PyTorch, due to its more "python-esque" approach to things, but I know many people that prefer Keras because of its clear and simple layout and documentation.

Providing a little more information, or your context, can also potentially increase the quality of the answers you receive.
