using unit vectors with `healpy`

Question

I have a collection of points on the sphere, given as just unit vectors in R3. I am trying to see if they are equidistributed, and for this I want to do a spherical harmonic transform (using healpy unless someone can suggest something better). What I can't understand is what format healpy wants its data in - the documentation seems to be opaque. Any words of wisdom would be appreciated.

Answer 1

You can take a look at the tutorial on mapping points to a map:

"Map data to a HEALPix grid." at https://healpy.readthedocs.io/en/latest/other_tutorials.html

But instead of hp.ang2pix, you can use hp.vec2pix.

Once you have a map, you can take histograms with numpy or power spectra with hp.anafast