# coding: utf-8 # # Three little quadratic functions # In[2]: get_ipython().magic(u'matplotlib qt') # In[1]: import numpy as np import matplotlib.pyplot as pt # Consider the three equations: # # $$y=x^2+\delta$$ # $$z=x^2-\delta$$ # $$y=z^2+\delta$$ # In[2]: delta = 0.5 # In[5]: from mpl_toolkits.mplot3d import Axes3D fig = pt.figure() ax = fig.add_subplot(111, projection='3d') res = 10j x, z = np.mgrid[-3:3:res,-3:3:res] y = x**2 + delta ax.plot_surface(x, y, z, color="red", cstride=1, rstride=1) if 1: y, x = np.mgrid[-3:3:res,-3:3:res] z = x**2 - delta ax.plot_surface(x, y, z, color="green", cstride=1, rstride=1) if 0: x, z = np.mgrid[-3:3:res,-3:3:res] y = z**2 + delta ax.plot_surface(x, y, z, color="blue", cstride=1, rstride=1) # Need better plotting tool. See corresponding three-quadratics.py.