#  Demonstration code for Scientific Computing class,
#  http://www.math.nyu.edu/faculty/goodman/teaching/SciComp2022/
#  IntegrandClass.py
#  Demonstrate a software package, with IntegrandDemo.py
#  and IntegrandClass.py

#  Integrate a function over [a,b] using the rectangle rule

def Integrate( f, a, b, n):
   """Use the rectangle rule to integrate from a to b using n points
      f is a class instance with f.f(x) being the value of the integrand
      at x
   """
   I  = 0.        # will be the integral
   dx = (b-a)/n   # distance between grid points
   
   for k in range(n):
      xk = a + k*dx
      I  = I + f.f(xk)*dx
   return I