how to integrate inside 'for' loop

Question

0 个投票

I am new to matlab. All i wanted was to integrate f(t)*cos(pi*n*t) over t through quadgk inside a loop where n varies from 1 to 10. But I guess the problem is that quadgk needs a function where only t is a variable and not n. how to do it???

    t=linspace(0,12,1000);
    T=2;
    Y=g(t)';
    rep=(t(end)-t([1]))/T;
    f=0;
    N=5;
    hold on;
    h=zeros(N,1);
    clr=lines(N);
    for n=1:2:N;
        line(t,Y,'linewidth',5)
        grid on;hold on;
        A=(1/T)*quadgk(@g,0,T);
        P=Y.*(cos(n*pi*t))';
        Q=Y.*(sin(n*pi*t))';
        Ax=(2/T)*quadgk(@s,0,T);
        Bx=(2/T)*trapz(t,Q)/rep;
        f=f+(Ax*cos(pi*n*t)+Bx*sin(pi*n*t));
        final=A+f;
        h(n)=plot(t,final,'linewidth',2,'Color',clr(n,:)); 
    end 
    hold off;
    legend(h, num2str((1:N)','harmonic-%d'))
function f=g(x)
z=2*floor(x/2);
x1=x-z;
y1=(1).*(0<=x1 & x1<=0.8);
y2=(-1).*(0.8<x1 & x1<2);
f=y1+y2;