Fix auto_clip_fac in case of resuming from checkpoint

[greaber]

When resuming from a checkpoint, self.iter is not zero, but self._h_max is still undefined, so the optimizer would error. The PR checks directly if self._h_max is defined, which should always work.

[JianGoForIt]

Hi @greaber

Thanks for catching the bug and submit the PR. For this error, I think the better way to resolve is to get h_max into the states saved and loaded.

Cheers,

Jian

[greaber]

I see. Is there any reason h_max and h_min can't just be set to 0 in __init__ and treated exactly as other parts of the state?