Re: PLplot package

[Joao Cardoso]

Mike Blatchley wrote:
> 
> Joao,
> 
> I have just managed to get plplot compiled on my computer, with a few
> patches here and there, and running its demos.  Also got plplot_octave.oct
> built.  I can run your plplot_octave_demo.m without errors, but the
> minute I try to execute standard octave-type plotting commands, I get the
> following error:
> 
>  Example from your INSTALL file:
>  octave:8> for i=[1:9 11:14 
> 19:20];feval(sprintf("p%d",i));kbhit;endfor;oneplot
>  X Error of failed request:  BadAccess (attempt to access private resource 
> denied)
>    Major opcode of failed request:  89 (X_StoreColors)
>    Serial number of failed request:  47
>    Current serial number in output stream:  62
>

I guess that you are running a True Color Xserver; such visual does
not support writing (modifying) the colormap. If you have more than
256 colors available, then probably you have a TRue Color xserver.
You can also check it typing `xrdb -symbols' an looking for string
"-DCLASS_". You can revert to a Pseudo Color visual by specifying
in your ~/.xserverrc (or whatever xserver configuration file your
redhat system uses) 

        exec /usr/X11R6/bin/X -dpi 100 -bpp 8

This should not be a problem for plplot if you dont change the colormap.
 From the examples provided, only the "shade" demo tries to do it.
try running the demos one by one, eg, `p1', `p2', etc.

> Each time, I can see a window flash on the screen very quickly, but then
> it goes away with the X error.  Any ideas what I might need to do,
> especially since all your demo scripts work? And, I do have your PLplot
> directory in octave's LOADPATH variable.

You can also check file `PLplot/pldef.m' and comment the lines
that exchange the background and foreground colors:

plSetOpt("bg", "FFFFFF");
plscol0(15, 0, 0, 0);
plscol0(0, 255, 255, 255);


> 
> I am running this on a RedHat 5.0 i686 machine with octave 2.0.11.
> 
> Thanks,
> 
> Mike B.
> address@hidden

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Joao Cardoso, INESC  |  e-mail:
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