[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
An other problem
From: 
John W. Eaton 
Subject: 
An other problem 
Date: 
Thu, 19 Jun 2003 23:17:34 0500 
On 20Jun2003, Yann Lamontagne a.k.a. daume <address@hidden> wrote:
 I am trying to plot
 function xdot = lorenz(x)
 xdot(1) = 10*x(2)  10*x(1)
 xdot(2) = x(1)*2.666  x(3)*x(1)  x(2)
 xdot(3) = x(1)*x(2)  28*x(3)
 end
 solution=lsode( "lorenz",[1, 1, 1], t = linspace(0.0,100, 5000))
 gset parametric
 gsplot(solution)

 the solution seems to have two sets of data and I believe it is plotting
 the wrong set, do anyone know how to fix that?
I think you are doing the right thing, but the set of equations that
you are using don't look like the same ones I have seen before. Also,
starting point is critical to getting a interesting behavior and a
pretty plot. If I use
function y = lorenz (x, t)
y = [10 * (x(2)  x(1));
x(1) * (28  x(3));
x(1) * x(2)  8/3 * x(3)];
endfunction
x = lsode ("lorenz", [3; 15; 1], (0:0.01:25)');
gset parametric
gsplot x
I get a plot that looks a lot like the one on the Octave home page
(but with 3d axes).
jwe

Octave is freely available under the terms of the GNU GPL.
Octave's home on the web: http://www.octave.org
How to fund new projects: http://www.octave.org/funding.html
Subscription information: http://www.octave.org/archive.html

 An other problem, Yann Lamontagne a.k.a. daume, 2003/06/19
 An other problem,
John W. Eaton <=