This article explains how to calculate the root of a function using the fsolve function.

The article is based on an English article "How to find the rooots of a function with fsolve".

The fsolve function returns the roots of a nonlinear equation defined by f(x) = 0. In this case we will calculate the root of the function f(x) = x^3.

Here is the code:

#Import fsolve para calcular la raiz de la funcion x^3

from scipy.optimize import fsolve

#Importar pylab

import pylab

#importar numpy

import numpy

#se calcula la potencia 3 de x con la funcion lambda

potencia3 = lambda x : x**3

#Se calcula la raiz de x^3 iniciando con x = 10

resultado = fsolve(potencia3,10) # starting from x = 10

print resultado

#Se define 400 valores de x entre -4 a 4

x = numpy.linspace(-4,4,400)

#Se genera la grafica, pasando el valor de x

#la potencia 3era de x, el valor de resultado, la potencia 3era de resultado

pylab.plot(x,potencia3(x),resultado,potencia3(resultado),'ro')

#Se define el grid

pylab.grid(b=1)

#Se muestra la grafica

pylab.show()

The plot shows the point where the root of the function is found:

Make a donation! If you liked the article you can make a donation with Bitcoin (BTC) using the digital wallet of your choice to the following address: 17MtNybhdkA9GV3UNS6BTwPcuhjXoPrSzV

Or by scanning the QR code from your wallet: