3049.sagews

var('x,y,z')
implicit_plot3d((x^2+y^2+z^2+2*y-1)*((x^2+y^2+z^2-2*y-1)^2-8*z^2)+16*x*z*(x^2+y^2+z^2-2*y-1), (x, -3, 3), (y, -3.1, 3.1), (z, -4, 4))

simplicial_complexes.KleinBottle()

Simplicial complex with 9 vertices and 18 facets

u, v = var('u,v')
fx = (3*(1+sin(v)) + 2*(1-cos(v)/2)*cos(u))*cos(v)
fy = (4+2*(1-cos(v)/2)*cos(u))*sin(v)
fz = -2*(1-cos(v)/2) * sin(u)
parametric_plot3d([fx, fy, fz], (u, 0, 2*pi), (v, 0, 2*pi), frame=False, color="green")

x, y, z = var("x, y, z")
T = 1.61803398875
p = 2 - (cos(x + T*y) + cos(x - T*y) + cos(y + T*z) + cos(y - T*z) + cos(z - T*x) + cos(z + T*x))
r = 4.77
implicit_plot3d(p, (-r, r), (-r, r), (-r, r), plot_points=40, zoom=1.2).show()

/sagenb/sage_install/sage-4.7/local/lib/python2.6/site-packages/sage/plot/plot3d/implicit_plot3d.py:256: DeprecationWarning: Unnamed ranges for more than one variable is deprecated and will be removed from a future release of Sage; you can used named ranges instead, like (x,0,2) G = ImplicitSurface(f, xrange, yrange, zrange, **kwds)