Re: Very slow mesh on MacOS X

[Joe Koski]

on 10/5/06 12:18 PM, Marcus Vinicius Eiffle Duarte at address@hidden wrote:

> Hey, folks!
>
> I am running octave-2.1.73 on a PPC G5 running MacOs X. I downloaded the binary from the HPC project.
> I am running a small program that integrates some ODEs and then plot results using the mesh function. The matrices have size 100 x 1000. The problem is, it takes about 10 minutes for the first gnuplot windows to show up, and about 10 minutes more for the second window to pop up. The PowerMac has 2 processors and 2 Gb RAM, and I can`t figure why it takes so long. 
> I ran the same script on my Windows box (octave-2.1.73 under cygwin), and it takes about 10 seconds to disply the first window and about 5 seconds more to display the second (thee numbers might be exaggerated, as I am using the windows box remotely, through RDesktop). 
>
> The relevant portion of the code is below
>
> <snippet>
> [ T, ISTATE, MSG ] = lsode( 'dTdt', [ Tf0z; Ts0z ], t );
>
> T = T'; %%% THIS IS 200 x 1000
>
> ISTATE
> MSG
>
>
> [ tt, zz ] = meshgrid( t, z ); %%% THESE ARE 100 x 1000 
>
>
> figure;
> mesh( tt, zz, T( 1 : N, : ) );
> xlabel( 'Time (h)' );
> ylabel( 'Length (m)' );
> zlabel( 'Tf' );
>
> figure;
> mesh( tt, zz, T( N + 1 : 2 * N, : ) );
> xlabel( 'Time (h)' );
> ylabel( 'Length (m)' ); 
> zlabel( 'Ts' );
> </snippet>
>
>
> Any clues on why this mesh takes so long to be displayed on MacOS X?
>
> Thanks,
>
> Marcus Vinicius
Marcus Vinicius,

What terminal are you using with gnuplot? AquaTerm or x11? If you are using AquaTerm, and have x11 installed, you can try the plot in x11 to see if that helps. You can also try to set the terminal to a postscript or some other format to see if that’s faster. 

If you have x11 installed but normally use AquaTerm, you can access x11 graphics by running octave in an xterm window after first doing “export GNUTERM=x11”.

Joe