MATLAB: I am trying to solve a second order ODE using Finite difference method.I have written a code as below but it shows error upon running.Can anyone help me find the potential error in the code.Thanks

finite difference methodode

function [x,U]=FD(a,b,ua,uxb,f,n)
a=0;b=10;n=100;
h=(b-a)/n;
h1=h*h;
A=sparse(n-1,n-1);
F=zeros(n-1,1);
for i=1:n-2
A(i,i)=-2/h1;A(i+1,i)=1/h1;A(i,i+1)=1/h1;
end
 A(n-1,n-1)=-2/h1;
for i=1:n-1
x(i)=a+i*h;
f=0.091875*cos(x(i));
F(i)=feval(f,x(i));
end
F(1)=F(1)-ua/h1;
F(n-1)=F(n-1)-uxb/hi;
U=A/F;
a=0;b=10;n=100;
ua=0;uxb=0;
[x,U]=FD(a,b,ua,uxb,'f',n);
plot(x,U,0);hold
u=zeros(n-1,1);
for i=1:n-1,
u(i)=0.091875*cos(x(i));
end
plot(x,u)
The error shown to be as ;
Error using feval
Argument must contain a string or function_handle.
Error in FD (line 14)
F(i)=feval(f,x(i));

Best Answer

f=@(x)0.091875*cos(x);
F(i)=feval(f,x(i));
Best wishes
Torsten.
Related Question