Nummerical integration

Hello there

I wish to evaluate three numerical integrals. I call a vector (vBL)from another file. Then I want to get a value from each integral for each value in vBL.

I tried symbolic integration, but that didn´t work for large number of n. Now I am trying numerical integration, but this is not working ether.

Anybody knows how to make this work.

Also, in the second integral vK(i) I need to differentiate vm(i) twice, could this give a problem when using numerical integration?

The code

function [vM,vK,vP]=generalized(E,I,L,m,T,n)

%Data E; %E-modul N/m^2 I; %Inertimomentet m^4 m; %ensfordelt masse kg/m L; %Længden m

for t=0:T/100:T;

P=25000; %Lasten

end n;%antal modes

%Kalder BL vektor

vBL=BLC(n);

vB=1/L*vBL;

%Beregning af den generaliseret masse, stivhed og last.

vM=zeros(n,1); vK=zeros(n,1); vP=zeros(n,1);

for i=1:1:n;

vm(i)=@(x) cosh(vB(i)*x)-cos(vB(i)*x)-(cosh(vBL(i))+cos(vBL(i)))/(sinh(vBL(i))+sin(vBL(i)))*(sinh(vB(i)*x)-sin(vB(i)*x));%Modeshape vektor

vM(i)=quad(m*vm(i).^2,0,L);

vK(i)=quad((E*I*diff(vm(i),x,2).^2),0,L);

vP(i)=quad(P*vm(i),0,L);

end

end

Thanks in advance

[Jan]

Please define "didn't work" with any details: too slow, wrong results (what did you expect), error message? Inn addition I suggest to format your code to increase the readability, see the "Markup help" link on this page.