Dictionary support for Undersampler

[bchen1116]

fix #2105

[codecov]

Codecov Report

Merging #2271 (f7404a6) into main (59e9dd0) will increase coverage by 0.1%.
The diff coverage is 100.0%.

@@            Coverage Diff            @@
##             main    #2271     +/-   ##
=========================================
+ Coverage   100.0%   100.0%   +0.1%     
=========================================
  Files         280      280             
  Lines       24336    24392     +56     
=========================================
+ Hits        24314    24370     +56     
  Misses         22       22             

Impacted Files	Coverage Δ
...s/components/transformers/samplers/base_sampler.py	100.0% <100.0%> (ø)
...s/components/transformers/samplers/undersampler.py	100.0% <100.0%> (ø)
evalml/tests/component_tests/test_components.py	100.0% <100.0%> (ø)
evalml/tests/component_tests/test_undersampler.py	100.0% <100.0%> (ø)

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[chukarsten]

This is good work, Bryan. I think I need some chat with what this means to have a ratio for both the majority and minority class. That's a little confusing to me now that I'm looking at it. I think we also need to drop an update to the docstring and figure out what _dictionary_to_params() should be doing without 'sampling_ratio_dict' defined in the params.

[chukarsten]

Solid work! Ship it!

[freddyaboulton]

@bchen1116 This looks good to me!

[freddyaboulton]

Should this method live in the base class? It would be different for undersamplers vs oversampler right?

[bchen1116]

I plan on doing an if-statement in the base class to handle the differences between over and undersamplers! Should be a one-line difference