I have 3 lists
ax.plot3D(x, y, z, linestyle = 'None', marker = 'o').
x > 0.5
It's impossible to verify a condition on every element of a list without iterating over it at least once. You could use numpy here for easy access to the elements after condition is passsed and do:
import numpy x = [0.0, 0.4, 0.6, 1.0] y = [0.0, 2.2, 1.5, 1.6] z = [0.0, 9.1, 1.0, 0.9] res = numpy.array([[x[i], y[i], z[i]] for i in xrange(len(x)) if x[i] > 0.5]) ax.plot3D(res[:,0], res[:,1], res[:,2], linestyle="None, marker='o'")