Include variance_combinations in the output of jenks.jenks()

[joaogb]

It seems to me that we should include variance_combinations in the output of jenks.jenks() instead of discarding the data. This would allow one to compute the goodness of variance fit, for example.

I suggest:

(...)
lower_class_limits, variance_combinations = jenks_matrices(data, n_classes)
(...)
return {'breaks':kclass, 'variance_combinations':variance_combinations}

[perrygeo]

That sounds like a good idea but would change the interface significantly. I'd accept a pull request if you wanted to make it a separate function.

[joaogb]

How about adding a parameter varInResults to the list of arguments? If true, the function would return the dict with the breaks and variance. Otherwise, it would return the breaks as it currently does. This parameter would default to False for backwards compatibility.

[perrygeo]

👍 sounds good to me, probably should follow the numpy convention and name it return_variance_dict