Handle warning of "Array is wrong shape or size" when plotting a geopolyshape and setting the ColorData field in MATLAB

MATLAB is throwing a warning and not plotting a geopolyshape when setting the ColorData field; however the shape is plotted when ColorData isn't set. The example code below demonstrates the issue. I am using MATLAB2024b.

Note the latitude and longitude correspond to a H3 resolution 8 hexagon. I don't think the issue is because it's an H3 cell because other H3 cells plot fine with ColorData but I'm sharing for completeness.

So how can I plot this geopolyshape while setting ColorData?

    lat = [41.9480823417544; ...
        41.9232620388895; ...
        41.9297343644414; ...
        41.9610354203583; ...
        41.9858827546380; ...
        41.9794019931882; ...
        41.9480823417544];
    
    lon = [-71.5797574810054; ...
        -71.5494225035612; ...
        -71.5033771429879; ...
        -71.4876121649763; ...
        -71.5179362450247; ...
        -71.5640362454369; ...
        -71.5797574810054];
    
    
    % Create geopolyshape
    shape = geopolyshape(lat, lon);
    
    figure;
    tiledlayout('flow');
    nexttile;
    geoplot(shape,'FaceColor','b');
    title('works')
    
    nexttile;
    geoplot(shape,'FaceColor','flat');
    title('works')
    
    nexttile;
    geoplot(shape,'FaceColor','flat','ColorData',1);
    title('fails and throws warning')
    
    nexttile;
    geoplot(shape,'ColorData',5);
    title('fails and throws warning')

Warning: Error creating or updating TriangleStrip
Error in value of property ColorData
Array is wrong shape or size

Answer 1

[Walter Roberson]

https://www.mathworks.com/help/map/ref/map.graphics.chart.primitive.line-properties.html#mw_f88b2538-674c-488f-bc33-da8b68310c74

ColorData — Line colors

Line colors, specified as a numeric vector that linearly maps to the colors in the current colormap. The plot uses a different color for each element of ShapeData. Specify ColorData as a vector the same length as ShapeData.

So, your problem is that you are passing in scalar ColorData, when it needs to be a vector the same length as the shape data.

[Andrew]

The shape has one element and ColorData also has one element. What is the correct length? Also shape is a polygon, not a line.

[Walter Roberson]

Hmmm, I don't know.

I do notice however that if you duplicate the shape and use colordata length 2, there is no warning.

    lat = [41.9480823417544; ...
        41.9232620388895; ...
        41.9297343644414; ...
        41.9610354203583; ...
        41.9858827546380; ...
        41.9794019931882; ...
        41.9480823417544];
    
    lon = [-71.5797574810054; ...
        -71.5494225035612; ...
        -71.5033771429879; ...
        -71.4876121649763; ...
        -71.5179362450247; ...
        -71.5640362454369; ...
        -71.5797574810054];
    
    
    % Create geopolyshape
    shape = geopolyshape(lat, lon);
    
    geoplot([shape;shape],'FaceColor','flat','ColorData',[5 5]);