function t = traprule(f,a,b)
%
%  The function t = traprule(f,a,b)
%    returns in t the application of the Trapezoidal Rule
%    to approximate the definite integral of f over [a,b].
%
%  Example: 
%    t = traprule('sin',0,1) % integral of sin(x) over [0,1]
%
fa = feval(f,a);
fb = feval(f,b);
t = (b-a)*(fa + fb)/2;