Hello i want invert a lemniscate but i find few information on internet, i know how to find the inverse of a function in rectangular coordinates functions but i dont know how to do it in polar coordiantes and how inverting a lemniscate become a hyperbola?.
i am using python for plot because is an assigment.
this is the equation:
r = (a**2)(np.cos(2rad))
import numpy as np
import matplotlib.pyplot as plt
import math
plt.axes(projection = 'polar')
a=3
rads = np.arange(0, (2 * np.pi), 0.01)
for rad in rads:
r = (a**2)*(np.cos(2*rad))
plt.polar(rad,r,'g.')
plt.show()
Best Answer
The set of MacLaurin polar curves obtained by inversion $ r\to \dfrac{a^2}{r}$
$$ r^n = a^n \cos n \theta, r^n = a^n \sec n \theta $$
In the particular case $n=2$ Lemniscate of Bernoulli and rectangular hyperbola are mutually invertible about radius of inversion circle $r=a=1$
An inversion transformation between Cartesian coordinates can be written
$$ (x,y)\to \dfrac{a^2\;(x,y)}{x^2+y^2}$$
For $n=1,3$ and inversions: