Scatter plot with scalar data

Question

I want to create a scatter plot with matplotlib where the data points have scalar data attached to them and are assigned a color depending on how large their attached value is relative to the other points in the set. I.e., I want something akin to a heatmap. However, I'm looking for a "discrete" heatmap, i.e. nothing should be ploted where there were no points in the original data set and, in particular, no interpolation (in space) should be performed.

Can this be done?

Answer 1

you can use scatter, and set the attached value to c parameter:

import numpy as np
import pylab as pl

x = np.random.uniform(-1, 1, 1000)
y = np.random.uniform(-1, 1, 1000)

z = np.sqrt(x*x+y*y)

pl.scatter(x, y, c=z)
pl.colorbar()
pl.show()