derivada1.py

from math import *

f=lambda x: cos(x)
df = lambda x: -sin(x) # a derivada de verdade
x=pi/3
h=0.1
print '{0:25} | {1:20} | {2!r}'.format("valor de h", "der. numerica", "erro absoluto")
for i in range(8):
    fp=(f(x+h)-f(x-h))/(2*h) # calcula a derivada numerica
    erroabs=abs(fp-df(x))
    print '{0:25} | {1:20} | {2!r}'.format(repr( h ),repr(fp),repr(erroabs))
    h=h/10**(i)
print "fim"