Bins array limits

[HIKassem]

windrose/windrose/windrose.py

Lines 373 to 375 in 47ab1b5

	bins = np.linspace(np.min(var), np.max(var), 6)
	if isinstance(bins, int):
	bins = np.linspace(np.min(var), np.max(var), bins)

In cases where bins argument isn't provided by the user. Both np.min and np.max functions may return nan if the var array has nan values. I think simply replacing them with np.nanmin and np.nanmax would fix this issue. Otherwise just an error message would be nice at this point because currently matplotlib throws an error which is hard to trace to this issue.

[ocefpaf]

While I do like the np.nan(min/max) idea I think that we should not assume a lot about user data. Maybe checking for NaNs and trowing an error is better and let the user fix that in the way they prefer, like specifying the bins or using the nan min/max themselves.

Do you want to send a PR for that?

[HIKassem]

Sure, no problem.