In order to do a cumulative stepped histogram we need to make the hist call in one shot instead of looping over the bands.
In order to do a cumulative stepped histogram
we need to make the hist call in one shot instead
of looping over the bands.

To do this I reshape the data array
 and supply a list of colors.

brendan-ward/rasterio,brendan-ward/rasterio,brendan-ward/rasterio