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[Feature request] I think there should be an easy and straightforward way to change opacity in plotly express cloropleth maps

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#5,431 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
plotly, python
Domain
data-visualization

Research direction

Start with the Plotly Express choropleth implementation and its existing continuous and discrete color-scale options. Check how vector borders and map layers are represented, then define the expected behavior for removing fill color or applying transparency while retaining borders. Done means the requested opacity and border-only behavior are supported and covered by relevant tests.

Written by the indexing model from the issue text.

Description

Many times in GIS and map visualization, it is useful to add a certain degree a transparency to a vector layer to see which features of the baseline map are covered by the tiles.
To my knowledge, there are options for selecting continuous and discrete color scales.
However, there isn't an option for removing the color altogether (visualizing only the vector borders) or changing the opacity of the color

Dominant language
Python
Stars
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Forks
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Avg merge
13h 41m
Merged PRs (30d)
21

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