Undefined variable problem in a simple model for non-linear oscillator
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Hey guys, I'm just trying to run a very simple function to help model a non-linear oscillator. Here's the code:
function vp=F(t,v);
vp=zeros(2,1);
vp(1)=v(2);
vp(2)= -(v(2)+v(1)+3*(v(1))^3)+20*cos(w*t);
I had to transform it into a 1st order eq b/c it seems like matlab can't handle second order equations for some reason. When I type in the following, I get an error saying "undefined function or variable 't'"
%[t,v]=ode45('F',[0,15],[0,0])
plot(t,v(:,1))
I'm not experienced with MatLab at all! Any help would be greatly appreciated.
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Paulo Silva
2011-2-28
1 个投票
"When I type in the following, I get an error saying "undefined function or variable 't'"
%[t,v]=ode45('F',[0,15],[0,0])
plot(t,v(:,1))"
You commented the line where the t was created therefore there's no t and matlab gives you that error
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