Plotting system of (implicit) equations in matplotlib [duplicate]

Question

First off, I'm new to python and matplotlib. I need to plot several systems of implicit equations in one figure.

The equations are in form of:

3x+2y=1

Is there an easy way to plot these, other than first making the equations explicit (i.e. y=...)?

Answer 1

import numpy as np
import matplotlib.pyplot as plt
# Note the order of y,x.
y,x=np.ogrid[-5:5:100j,-5:5:100j]
plt.contour(x.ravel(),y.ravel(),3*x+2*y,[1])
plt.show()

Answer 2

You can use contour() to do implicit plots in two space dimensions:

x = numpy.linspace(-2., 2.)
y = numpy.linspace(-2., 2.)[:, None]
contour(x, y.ravel(), 3*x + 2*y, [1])

In 3 dimensions, I suggest using Mayavi instead of matplotlib.