reimplement rgbas

[knaaptime]

• fixes a bug when the 'scheme' argument is passed
• reimplement using matplotlib's vectorized method; much faster
• give back numpy instead of lists

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 92.85714% with 1 line in your changes missing coverage. Please review.

Project coverage is 89.5%. Comparing base (af62513) to head (3f53485). Report is 6 commits behind head on main.

Additional details and impacted files

[](https://app.codecov.io/gh/pysal/mapclassify/pull/228?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pysal) ```diff @@ Coverage Diff @@ ## main #228 +/- ## ======================================= - Coverage 89.6% 89.5% -0.1% ======================================= Files 9 9 Lines 1125 1127 +2 ======================================= + Hits 1008 1009 +1 - Misses 117 118 +1 ``` | [Files](https://app.codecov.io/gh/pysal/mapclassify/pull/228?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pysal) | Coverage Δ | | |---|---|---| | [mapclassify/util.py](https://app.codecov.io/gh/pysal/mapclassify/pull/228?src=pr&el=tree&filepath=mapclassify%2Futil.py&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pysal#diff-bWFwY2xhc3NpZnkvdXRpbC5weQ==) | `88.0% <92.9%> (-3.3%)` | :arrow_down: |

[knaaptime]

updated and renamed with an example if @martinfleis or @sjsrey want to have a look