help in capturing matrix patterns to files

[Harald Pfeiffer]

Hello,

That's a pity that this is not implemented.  As soon as I saw Razi's 
question, I thought that this would be a really useful feature.  I have 
found myself many times saying in talks that my matrix is non-symmetric 
for this-or-that reason.  Having a picture of the matrix to make the 
point would be very powerful.

I guess, outputting a picture with as many pixels as the matrix-size in 
a non-compressed format (tiff?) should be straightforward: You iterate 
through all matrix entries, if the entry is non-zero, you output "1", 
otherwise "0".
You could even output different colors depending on the size or sign of 
an entry.  This will result in huge files, but any image-software should 
be able to down-size and convert to more efficient formats.

Harald


Matthew Knepley wrote:
> There is nothing built into PETSc to do this. It is also X-Windows
> render commands inside. I used a screen capture program on
> the Window it pops up.
>
>   Thanks,
>
>      Matt
>
> On 5/4/06, *abdul-rahman at tu-harburg.de 
> <mailto:abdul-rahman at tu-harburg.de>* <abdul-rahman at tu-harburg.de 
> <mailto:abdul-rahman at tu-harburg.de>> wrote:
>
>     Hi all,
>
>     I'd appreciate if anyone can point to a tutorial/example on how to
>     direct
>     the matrix pattern plot (one with -mat_view_draw) to a file
>     (preferrably
>     PNG for presentation and postscript for publications)
>
>     I want to be able to capture the patterns in monochrome and also
>     resize
>     the graphics size.
>
>     Thanks so much.
>
>
>     Razi
>
>
>
>
> -- 
> "Failure has a thousand explanations. Success doesn't need one" -- Sir 
> Alec Guiness 

-- 
Harald P. Pfeiffer                harald at tapir.caltech.edu
Theoretical Astrophysics          Phone (626) 395-8413
Caltech 130-33                    Fax   (626) 796-5675
Pasadena, CA 91125, USA