Numerical volume integral with keeping parameters

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dont panic
dont panic on 9 Sep 2013
HI ,
I wanted to calculate the magnetic potential of a bar magnet by numerical integration of the potential of a point source over the volume of the magnet. Below is my source code but I always get an error message.
Thank you for your help
a=0.0025; L=0.005; phis=0;
r1=0; r2=a; phi1=0; phi2=2*pi; z1=-L/2; z2=L/2;
f=@(r,phi,z,R,Z) (sin(phis-phi).*r)/(R.^2-2.*r.*R.*cos(phis-phi)+r.^2+(Z-z).^2).^(3/2);
[R,Z] = meshgrid(-0.05:s:0.05); mp=zeros(size( R ));
for k = 1:numel( R )
g = @(r,phi,z) f(r,phi,z,R(k),Z(k));
mp(k) = triplequad(g,r1,r2,phi1,phi2,z1,z2);

Answers (1)

Mike Hosea
Mike Hosea on 11 Sep 2013
Well, for starters, you need to change / to ./ in the definition of f. Second, however, you will need to use integral3 instead of triplequad.
Mike Hosea
Mike Hosea on 11 Sep 2013
Sorry, on second thought, you may not need INTEGRAL3. When I ran this, all I got were answers that numerically were not distinguishable from zero, and there is a singularity when R=0 and Z=0. There must be something wrong with your formulation.

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