root buat sendiri

# -*- coding: utf-8 -*-
"""
Created on Mon Mar 23 10:43:03 2020

@author: varenza
"""

import numpy as np

def fungsi(xi):
    fxi = xi**3-0.165*xi**2+3.993e-4
    return fxi
def dfungsi(xi):
    eps = 1e-5
    fplus = fungsi(xi+eps)
    fmin = fungsi(xi-eps)
    dfxi = (fplus-fmin)/(2*eps)
    return dfxi

tol = 0.01
iterasi = 1
xold = 0.05
fold = fungsi(xold)
dfold = dfungsi(xold)
x = np.array([xold])
fx = np.array([fold])
xnew = xold - fold/dfold
ea = abs((xnew-xold)/(xnew))*100

while ea >= tol:
    iterasi += 1
    xold = xnew
    fold = fungsi(xold)
    dfold = dfungsi(xold)
    x = np.append(x,xold)
    fx = np.append(fx,fold)
    xnew = xold-(fold/dfold)
    ea = abs((xnew-xold)/(xnew))*100
fnew = fungsi(xnew)


tabel = np.zeros([iterasi,3])
tabel[:,0] = np.arange(1,iterasi+1)
tabel[:,1] = x
tabel[:,2] = fx
for baris in tabel:
    print('{:^9.0f} {:11.9f} {:>12.4e} '.format(*baris))
print('Akar persamaan = {:.9f} dengan nilai f(x) = {:.4e}'.format(xnew,fnew))