3D Contour plot from data using Mayavi / Python

Question

I would like to do a 3D contour plot using Mayavi in exactly the same way as the third figure on this page (a hydrogen electron cloud model) :

http://www.sethanil.com/py

Answer 1

You can use delaunay3d filter to create cells from points. Then you can create an iso_surface() for the output UnstructuredGrid of delaunay3d. If you want ImageData, you can use image_data_probe filter.

import numpy as np
from tvtk.api import tvtk
from mayavi import mlab

points = np.random.normal(0, 1, (1000, 3))
ug = tvtk.UnstructuredGrid(points=points)
ug.point_data.scalars = np.sqrt(np.sum(points**2, axis=1))
ug.point_data.scalars.name = "value"
ds = mlab.pipeline.add_dataset(ug)
delaunay = mlab.pipeline.delaunay3d(ds)
iso = mlab.pipeline.iso_surface(delaunay)
iso.actor.property.opacity = 0.1
iso.contour.number_of_contours = 10
mlab.show()