pos_falsa.py

import math

pi = math.pi
cos = math.cos

def f(x):
    return cos(pi*(x+1)/8.0) + (0.148*(x)) -0.9062

def mod(x):
    if x > 0:
        return x
    else:
        return (-1*x)

def x(a,b):
    return ((a*mod(f(b))) + (b*mod(f(a))))/(mod(f(a)) + mod(f(b)))

y = 1
b = 0
k = 1
while y > 10**(-3):
    b = x(-1, b)
    y = f(b)
    print ("x%d = %f f(x%d) = %f" % (k, b, k, y))
    k+=1