Plotting elliptical orbits

Question

I\'m trying to write a code that plots the elliptical paths of an object using the equation for the ellipse r=a(1-e^2)/(1+e*cos(theta)). I\'d also like this data to be put

Answer 1

Do not call plt.polar once for every point. Instead, call it once, with all the data as input:

import numpy as np #Imports Python mathematical functions library
import matplotlib.pyplot as plt #Imports plot library
cos = np.cos
pi = np.pi

a = 5
e = 0.3
theta = np.linspace(0,2*pi, 360)
r = (a*(1-e**2))/(1+e*cos(theta))
plt.polar(theta, r)

print(np.c_[r,theta])

plt.show()

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By the way, numpy can do the calculation as a two-liner, instead of using a while-loop:

theta = np.linspace(0,2*pi, 360)   # 360 equally spaced values between 0 and 2*pi
r = (a*(1-e**2))/(1+e*cos(theta))  

This defines theta and r as numpy arrays (rather than single values).