Re: [Matplotlib-users] How to plot only points which lie in a certain range

[Pierre GM <bac...@gm...>]

On Monday 27 October 2008 18:40:07 marcusantonius wrote:
> I'm sorry for this newbie question. I have a data file consisting of 3
> columns, and want to plot the first versus the second column, but only if
> the parameter in the third column lies in a certain range. Does somebody
> have an idea how to do that?

Using masked arrays ?
import numpy as np
import numpy as ma
import matplotlib.pyplot as mpl

x = ma.arange(10)
y = ma.array(np.random.rand(10))
z = ma.array(np.random.rand(10))
(z_lo, z_up) = (0.1, 0.8)
x[ (z<z_lo) | (z>z_up) ] = ma.masked
mpl.plot(x,y, 'ok-')

Alternatively,

x = ma.masked_where((z<z_lo) | (z>z_up), x)