Re: [Matplotlib-users] Artefacts in contour plot?

[Dominique O. <Dom...@po...>]

I have made several experiments; I have installed the latest matplotlib 
(with the 'contour' update) in both Win XP and SuSE Linux Pro 9.1. I 
made sure to uninstall everything pertaining to matplotlib before 
installing the latest version. In Windows, I use the pre-built 
distribution, and in Linux I compile it myself. The situation is this:

- In Linux, some zigzagging lines appear when there are few points to 
interpolate. Eg, if i generate my grid from
	x = y = arange( -1, 1, delta ),
zigzags would appear for small values of delta. However, it seems that 
those zigzags are a normal consequence of a small value of delta. For 
larger deltas, the contours are beautiful.

- In XP, the same as above happens. But I see additional lines that 
don't seem to represent anything meaningful. I made sure I was 
performing a clean install. Are there updates to other packages I should 
consider? Pygtk? This happened with both the TkAgg and GTKAgg backends. 
Perhaps I should try compiling matplotlib myself?

If anyone is able to reproduce the problem, then it might indeed be a 
problem. If not, perhaps something is funny with my box.

Thanks,
Dominique