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Plotting a polynomial in Python

I am new to Python plotting apart from some basic knowledge of matplotlib.pyplot. My question is how to plot some higher degree polynomials? One method I saw was expressing y in terms of x and then plotting the values. But I have 2 difficulties:

  1. y and x cannot be separated.
  2. I am expecting a closed curve(actually a complicated curve)

The polynomial I am trying to plot is:

c0 + c1*x + c2*y +c3*x*x + c4*x*y + c5*y*y + c6*x**3 + c7*x**2*y + ..... c26*x*y**5 + c27*y**6

All coefficients c0 to c27 are known. How do I plot this curve?

Also could you please suggest me resources from where I can learn plotting and visualization in Python?

Clarification: Sorry everyone for not making it clear enough. It is not an equation of a surface (which involves 3 variables: x, y and z). I should have put a zero at the end: c0 + c1*x + c2*y +c3*x*x + c4*x*y + c5*y*y + c6*x**3 + c7*x**2*y + ..... c26*x*y**5 + c27*y**6 =0

like image 231
Ally Avatar asked Aug 06 '13 18:08

Ally


1 Answers

I'm not sure I fully understood your question, but I think you want a surface plot

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

x = np.arange(-5, 5, 0.25)
y = np.arange(-5, 5, 0.25)
X, Y = np.meshgrid(x, y)
F = 3 + 2*X + 4*X*Y + 5*X*X

fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.plot_surface(X, Y, F)
plt.show()

And for the resources: official documentation and pyvideos

like image 80
Viktor Kerkez Avatar answered Sep 22 '22 08:09

Viktor Kerkez