import numpy as np
import holoviews as hv

hv.extension('matplotlib')

data = [(chr(65+i), chr(97+j),  i*j) for i in range(5) for j in range(5) if i!=j]
hv.HeatMap(data).sort()

heatmap = hv.HeatMap([(0, 0, 1), (0, 0, 10), (1, 0, 2), (1, 1, 3)])
heatmap + heatmap.aggregate(function=np.max)

heatmap = hv.HeatMap((np.random.randint(0, 10, 100), np.random.choice(['A', 'B', 'C', 'D', 'E'], 100), 
                      np.random.randn(100), np.random.randn(100)), vdims=['z', 'z2']).sort().aggregate(function=np.mean)

heatmap.opts(colorbar=True, fig_size=250, clim=(-2, 2))