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matlabodematlab-deploymentdifferential-equations

Passing arguments in ode45

I want to pass a simple argument in my ode45 function. My function is as follows:

function dxdt = state( t,x,vgth,vgval)
p=1;
k=10^0.7;
window1=1-((2*x)-1).^(2*p);
dxdt=k*(vgval-vgth+1.2)*window1;  
end

The main script is:

clear all
step=0.01;
t = 0:step:10;
f=2*0.157;
vg = 5*sin(2*f*t);
x0=0.01;
vgth=1.9;
[t,x] = ode45(@(t,x) state1 (t,x,vgth,vg(t)), t, x0);
plot(t,x)

Here When I exclude the parameter vg(t) in the argument passing, the whole works just fine. But It doesn't work with vg(t) in the argument.

Solution

  • Assembling the comments to an answer:

    function dxdt = state( t,x,vgth,vgval)
    p=1;
    k=10^0.7;
    window1=1-((2*x)-1).^(2*p);
    dxdt=k*(vgval-vgth+1.2)*window1;  
end

function vgval = vg(t)
    f=2*0.157;
    vgval = 5*sin(2*f*t);  
end 

step=0.01;
t = 0:step:10;
x0=0.01;
vgth=1.9;
[t,x] = ode45(@(t,x) state(t,x,vgth,vg(t)), t, x0);

    This should hopefully work as intended.