pcolor and "interp" [changeset-2]

[Ben Abbott]

On Oct 2, 2008, at 3:24 PM, Ben Abbott wrote:

> On Thursday, October 02, 2008, at 12:50PM, "John W. Eaton" <jwe at bevo.che.wisc.edu 
> > wrote:
>> On  2-Oct-2008, Ben Abbott wrote:
>>
>> | Trying again. This time with the facecolor bug reported by Michael
>> | included.
>>
>> OK, I thought I had made the change, checked it in, and pushed it,  
>> but
>> I must have forgotten to push.  In any case, your latest changes
>> should be in the public archive now.
>>
>> Now I see that for something like
>>
>> pcolor (peaks ())
>> shading interp
>>
>> I get an all green plot.  I'm using gnuplot 4.2.2.  I assumed that it
>> would just fail to do the interpolation, but now the plot changes to
>> something completely wrong.  I'm a bit surprised by that as I thought
>> the previous behavior was that "shading interp" simply had no effect.
>>
>
> This due to an improper zrange being specified. If you save the  
> gnuplot commands and remove the zrange line it should work properly.
>
> To me honest, I was worried about that, but when I tested it  
> (switching between a standard gnuplot 4.2.3 and one patched for  
> interpolate colors) ... all went well. I doubt the difference is  
> that I'm running 4.2.3. It is more likely I did the testing wrong.
>
> Ben

I've rebuilt octave from the developers sources last night and  
installed two gnuplot binaries which I switch between using  
gnuplot_binary().

For me the unpatched gnuplot 4.2.3 and octave 3.1.51+ produce surface  
plots as seen with octave 3.0.2 and gnuplot 4.2.3. While the patched  
gnuplot 4.2.3+ and octave 3.1.51+ now properly interpolate colors.

I've attached a "debug.gp" file created with the commands below while  
running octave 3.1.51+ with the unpatched gnuplot 4.2.3.

	octave-3.1.51+:1> gnuplot_binary
	ans = gnuplot
	octave-3.1.51+:2> pcolor(peaks());
	octave-3.1.51+:3> shading interp; drawnow ("x11", "/dev/null", false,  
"debug.gp")

I'd be interested in hearing what others see rendered when they type

	$ gnuplot -persist debug.gp

I'm especially interested in the results from gnuplot 4.2.2, and 4.2.4.

Ben