Log unreduced results as histogram with EvalResult

[dilip]

@leo

Do you think it would be possible to just reuse the reduction implementation from the EvalResult class? By returning something like return EvalResult.SOMEMAGICMETHOD(validation_step_output_result) ?

You probably could by accessing whatever reduce function you specify when you add anything to the result for any given step.

@leo

And as a follow up question: Is there an _epoch_end method which operates on all ddp results gathered from the individual processes? So the analog of validation_step_end , but executed after the epoch has finished?

Do you definitively need to do this gathering on epoch ending? Is there any way you can refactor to just gather the results using the step end methods? I’m not sure otherwise how to gather, other than to use PyTorch’s distributed API.