strange behavior from gnuplot

[Mikel Maron]

Hello!

I have just begun using octave (on cygwin), having worked with matlab
at my university.

As a first try, I ran my small matlab file, which plots a set of
differential equations (the Lokta-Volterra predator-prey model).

After plotting several dozen points, with "hold on", gnuplot slows down
significantly, and after several hundred points, freezes completely. My
fuzzy diagnosis: gnuplot can only hold so many plots, even if there are
simply a single point.

Perhaps there is something naive in my code/plot. Perhaps something
else. Suggestions and help much appreciated. Code is pasted in below.

Mikel

call like "predatorPrey(0.05, 60, 100, 5)"

==========================================

function predatorPrey(h, length, OldX, OldY)
    NumTimeSteps = length / h;
    PauseFlag = true;
   
    hold on;
    for s = 1:NumTimeSteps
        [x,y] = growth(OldX, OldY, h);
        
        plot([s*h],[x],'bx;;');
        plot([s*h],[y],'rx;;'); 
        
        if (PauseFlag || s == 100)
            r=input('press enter to continue, 0 and enter to stop
pausing\n');
           if (r==0) PauseFlag = false; end
       end;
        
        OldX = x;
        OldY = y;
    end;
    hold off;
    
function [x,y] = growth(OldX, OldY, h)
    r = 0.6; a = 0.05; f = 0.1; q = 0.4;
    x = OldX + h *(r * OldX - a * OldX * OldY);
    y = OldY + h *(f * a * OldX * OldY - q * OldY);


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