[Matplotlib-users] Lines drawn across NaN data

[Goyo <goy...@gm...>]

I'm having trouble plotting data with NaN values. My plot has lines and
markers and usually both are skipped for NaN values. But when I have
more than 127 data a line is drawn from the last non-NaN to the next.

I read somewhere about a similar issue (maybe here? sorry I can't find
it just now), it seems like it has to do with some optimization
performed for large datasets and the use if lineto instead of moveto or
something like that. It was supposed to be fixed in 0.98.2 but I'm using
0.98.3 from Benjamin Drung's PPA (http://ppa.launchpad.net/bdrung).

This code shows the difference between plotting 127 and 128 data (look
at the left of each figure):

import pylab as pl
x = pl.random(128)
x[4:7] = pl.NaN
y = x[:-1]
pl.figure(1)
pl.plot(x, '-o')
pl.grid(True)
pl.figure(2)
pl.plot(y, '-o')
pl.grid(True)
pl.show()

Is this a known issue? Is there any workaround?

Thanks

Goyo