import numpy as np
def f(x):
  return np.exp(x)
def integ_tz(f, x0, x1, N=1000):
  s0=0.
  h=(x1-x0)/N
  x=x0
  for i in range(0, N):
    
    s0+=(f(x)+f(x+h))*h/2
    x+=h
  return s0
if __name__=='__main__':
  N=1000
  sum=integ_tz(f, 0, 2.5, N)
  print("integral exp(x) from x=0 to 2.5: ", sum, sep='')