Re: [matplotlib-devel] bugs found

[Tennessee L. <ten...@te...>]

On Mon, 2006-03-13 at 20:08 -1000, Eric Firing wrote:
> Tennessee Leeuwenburg wrote:
> > I've sent Eric the files off-list. Anyone else who wants them, let me
> > know. The bundle is about 400Kb -- not huge but not tiny. The script
> > itself is small, it's just the data file and the output images which
> > take up the space.
> > 
> > The .png and onscreen renderer are both missing line segments, and
> > behave in the same way. The .svg renderer behaves as expected.
> > 
> > I'm running a very up-to-date linux, and I installed matplotlib newly
> > about 4 days ago.
> > 
> > Cheers,
> > -T
> 
> Tennessee,
> 
> The first thing I notice is that you are trying to plot with log-log 
> scales, but some of your y values are zero.  Log(0) is undefined. The 
> Agg renderers are doing something sensible: leaving out the 0 values. 
> It is actually the ps and svg renderers that are incorrect, in that they 
> seem to be substituting a value of 1 for each zero; they are bridging 
> what *should* be gaps.
> 
> Eric

That could certainly explain it. 

I don't know that I agree that it's correct -- I'm not graphing log(X),
I'm graphing X, and 0 is a valid value for it. Only the scale is
logarithmic, but it still contains a 0. I'll bow to a more expert
opinion if there's disagreement.

Cheers,
-T