The colorbar command creates a plot structure that will display as a vertical color bar with labels next to a plot.  The first argument determines the range. The specific labels and how they are displayed can be controlled with the options described in plot/colorbar.

$\mathrm{plots}:-\mathrm{display}\left(\mathrm{plottools}:-\mathrm{polygonbyname}\left(4\,\mathrm{color}=''Viridis\; 128''\right)\,\mathrm{plottools}:-\mathrm{colorbar}\left(1..255\,''Viridis''\right)\right)$

The plottools[colorbar] command was introduced in Maple 2024.

For more information on Maple 2024 changes, see Updates in Maple 2024.