# test_passing_function.py
def f(x):
  return x*x

def trap_int(f, xmin, xmax, nstep): # integrate f(x) from xmin to xmax
  area=(f(xmin)+f(xmax))/2.0
  h = (xmax-xmin)/nstep
  for i in range(1,nstep):
    x = xmin+i*h
    area = area + f(x)

  return area*h # trapezoidal method

print "test_passing_function.py running"
xmin = 1.0
xmax = 2.0
n = 10
area = trap_int(f, xmin, xmax, n)
print "trap_int area under x*x from ",xmin," to ",xmax," = ",area