Copyright (C) 2020 Andreas Kloeckner
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import numpy as np
import matplotlib.pyplot as pt
def f(x):
return np.exp(x) - 2
def df(x):
return np.exp(x)
xgrid = np.linspace(-2, 3, 1000)
pt.grid()
pt.plot(xgrid, f(xgrid))
What's the true solution of $f(x)=0$?
Now let's run Newton's method and keep track of the errors:
errors = []
x = 2
At each iteration, print the current guess and the error.
for err in errors:
print(err)
Let's check: