`IndexError` in Choropleth when providing `bins` as a sequence.

Firstly, thanks to the contributors for this great package, it makes it really easy to make pretty awesome looking maps.

Please add a code sample or a nbviewer link, copy-pastable if possible

Sample code to generate error:

    column_name = 'example_column_name'
    bin_intervals = [0,10,20,30,40,50,100]
    folium.Choropleth(
        geo_data=gdf,
        name=f'{column_name} Choropleth',
        data=data,
        columns=['id', column_name],
        key_on='feature.properties.id',
        bins=bin_intervals,
        fill_color='YlOrRd',
        fill_opacity=0.7,
        line_opacity=0.2,
        legend_name=f'{column_name} (%)',
        show=True
    ).add_to(m)

Problem description

I am getting an IndexError when drawing a Choropleth using a bins parameter as a sequence.

Sample of the stacktrace from code quoted above:

.../folium/features.py in color_scale_fun(x)
   1007
   1008                 color_idx = np.digitize(value_of_x, bin_edges, right=False) - 1
-> 1009                 return color_range[color_idx], fill_opacity
   1010
   1011         else:

IndexError: list index out of range

Drawing a choropleth with a provided sequence for bins is expected to work and not result in an error.

Expected Output

A correctly drawn map with choropleth according to the given bins parameter is expected.

Output of folium.__version__

I was using the latest release 0.8.3, I cannot check this now as I am using my own edited version of the 0.8.0 branch where I “fixed” the issue.

Custom fix

I was able to get a correctly drawn map with bins working as expected by cloning branch v.0.8.0 and changing line 1073 in folium/features.py:

            nb_bins = len(bin_edges) - 1

to

            nb_bins = len(bin_edges)

Doing the same on the master branch made my layer selection button disappear.

I didn’t have the time to check if this will break anything else, and hence would not want to create a PR with this change 😃

[LeonardoFurtado]

I will try fix it.

[muneebable]

I have the same bug while working with Choropleth. And I am able to solve by this https://github.com/python-visualization/folium/issues/1130#issuecomment-504949715 So this issue hasn’t been solved yet.