One-hot-encode categorical column

[michcio1234]

Previously it was impossible.

[codecov]

Codecov Report

Merging #22 into master will increase coverage by 0.22%.
The diff coverage is 91.66%.

@@            Coverage Diff             @@
##           master      #22      +/-   ##
==========================================
+ Coverage   82.73%   82.96%   +0.22%     
==========================================
  Files           6        6              
  Lines         672      681       +9     
==========================================
+ Hits          556      565       +9     
  Misses        116      116

Impacted Files	Coverage Δ
sparsity/dask/reshape.py	94.73% <ø> (ø)	⬆️
sparsity/sparse_frame.py	85.6% <91.66%> (+0.32%)	⬆️

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[michcio1234]

@kayibal I'd like to merge it.

[kayibal]

Ok I'm not sure if it is necessary to have this complicated logic to check which categories to use? One could just say if the column is categorical everything is already known and the categories argument could be ignored. But I think it doesn't do much harm either!

[michcio1234]

Thanks for the comment. You're partially right - if we have categorical column, then everything should be known. But we cannot ignore categories argument, because it actually tells the function which columns should be encoded. And I wouldn't write this complicated logic if tests didn't actually rely on the order of returned one-hot-encoded columns.

[kayibal]

Ah ok I understand :)