fseries1.m

Communition MATLAB (Proakis)书的源程序

function xx=fseries1(funfcn,a,b,n,tol,p1,p2,p3)
%FSERIES  	Returns the Fourier series coefficients.
%		XX=FSERIES(FUNFCN,A,B,N,TOL,P1,P2,P3)
%		funfcn=The given function, in an m-file.
%		It can depend on up to three parameters
%		p1,p2, and p3. The function is given
%		over one period extending from 'a' to 'b'
%		xx=vector of length n+1 of Fourier Series
%		Coefficients, xx0,xx1,...,xxn.
%		p1,p2,p3=parameters of funfcn. 
%		tol=the error level.

j=sqrt(-1);
args0=[];
for nn=1:nargin-5
  args0=[args,',p',int2str(nn)];
end
args=[args0,')'];
t=b-a;
xx(1)=eval(['1/(',num2str(t),').*quad(funfcn,a,b,tol,[]',args]);
for i=1:n
 new_fun='exp_fnct';
 args=[',',num2str(i),',',num2str(t),args0,')'];
 xx(i+1)=eval(['1/(',num2str(t),').*quad(new_fun,a,b,tol,[]',args]);

end