#include        "trapezoidal.h"

double trapezoidal(Func &f, double a, double b, int n=100)
{
  double sum = 0.5*(f(a)+f(b));
  double h = (b-a)/n;
  for ( int i = 1; i < n; i++ )
    sum = sum + f(a+i*h);

  return sum*h;
}