Colormaps

HoloViews supports a wide range of colormaps, each of which allow you to translate numerical data values into visible colors in a plot. Here we will review all the colormaps provided for HoloViews and discuss when and how to use them.

The Styling_Plots user guide discusses how to specify any of the colormaps discussed here, using the cmap style option:

import numpy as np
import holoviews as hv
hv.extension('matplotlib')

ls  = np.linspace(0, 10, 400)
x,y = np.meshgrid(ls, ls)
img = hv.Image(np.sin(x)*np.cos(y)+0.1*np.random.rand(400,400), 
               bounds=(-20,-20,20,20)).opts(colorbar=True, xaxis=None, yaxis=None)

hv.Layout([img.relabel(c).opts(cmap=c) for c in ['gray','PiYG','flag','Set1']])