import numpy as np
import holoviews as hv
from holoviews import opts

hv.extension('bokeh')

np.set_printoptions(precision=2, linewidth=80)
opts.defaults(opts.Layout(shared_axes=False))

def f(x,y): 
    return x+y/3.1
    
region=(-0.5,-0.5,0.5,0.5)

def coords(bounds,samples):
    l,b,r,t=bounds
    hc=0.5/samples
    return np.meshgrid(np.linspace(l+hc,r-hc,samples),
                       np.linspace(b+hc,t-hc,samples))

f5=f(*coords(region,5))
f5

r5 = hv.Raster(f5, label="R5")
i5 = hv.Image( f5, label="I5", bounds=region)
h5 = hv.HeatMap([(x, y, round(f5[4-y,x],2)) for x in range(0,5) for y in range(0,5)], label="H5")

h5_labels = hv.Labels(h5).opts(padding=0)

r5 + i5 + h5*h5_labels

"r5[0,1]=%0.2f  r5.data[0,1]=%0.2f  i5[-0.2,0.4]=%0.2f  i5[-0.24,0.37]=%0.2f  i5.data[0,1]=%0.2f" % \
(r5[1,0],       r5.data[0,1],       i5[-0.2,0.4],       i5[-0.24,0.37],       i5.data[0,1])

f10=f(*coords(region,10))
f10

r10 = hv.Raster(f10, label="R10")
i10 = hv.Image(f10, label="I10", bounds=region)
r10+i10

"r10[0,1]=%0.2f  r10.data[0,1]=%0.2f  i10[-0.2,0.4]=%0.2f  i10[-0.24,0.37]=%0.2f  i10.data[0,1]=%0.2f" % \
(r10[1,0],       r10.data[0,1],       i10[-0.2,0.4],       i10[-0.24,0.37],       i10.data[0,1])

sl10=i10[-0.275:0.025,-0.0125:0.2885]
sl10.data

sl10

r5[0:3,1:3] + r5[0:3,1:2]

e10=i10.sample(x=-0.275, y=0.2885)
e10.opts(height=75)

r10=i10.sample(y=0.2885)
r10