redtrap.m

various matlab programs to slove various problems

function inte=redtrap(a,b,phi1,phi2,m,fun)
H=(b-a)/m; xx=[a:H:b]; dim=max(size(xx));
for i=1:dim, x=xx(i); d=eval(phi2); c=eval(phi1); h=(d-c)/m; 
 y=[c:h:d]; w=eval(fun); psi(i)=h*(0.5*w(1)+sum(w(2:m))+0.5*w(m+1)); 
end; inte=H*(0.5*psi(1)+sum(psi(2:m))+0.5*psi(m+1));