contour_surf contours argument is broken

[adamreeve]

The documentation for the contours argument to mlab.contour_surf says, "Specifying 0 shows no contours," but specifying 0 actually gives an error:

AssertionError: The contours argument must be positive

I also have many other problems with this argument but I've only been able to test them on 3.3, so I'm not sure if they still apply:

• Passing a list to the contours parameter seems to have no effect, the resulting contours are the same no matter what I put in the list.
• Passing an integer as the contours parameter actually gives me two less than that number of contour levels. So I have to pass 3 to get one set of contour lines.

[adamreeve]

Looks like the number of contours is correct, it's just that there are two contours at the very maximum and minimum that don't actually show up.

[adamreeve]

Small test example, I'd expect contours at 0.0 and 1.0, but instead I get 8 contours. This is tested on the latest git master (16305d9).

import numpy
from mayavi.mlab import *

def f(x, y):
    sin, cos = numpy.sin, numpy.cos
    return sin(x+y) + sin(2*x - y) + cos(3*x+4*y)

x, y = numpy.mgrid[-7.:7.05:0.1, -5.:5.05:0.05]

fig = figure(bgcolor=(1.0, 1.0, 1.0), fgcolor=(0.2, 0.2, 0.2))
s = contour_surf(x, y, f, contours=[0.0, 1.0])
s.contour.contours = [0.0, 1.0]
a = axes()
show()

[adamreeve]

Marking as fixed as pull request #30 has been merged.