Functionality to create Healpix maps from catalogues

[laurawolz]

Description

We need a function which creates Healpix sky density map based on an input catalogue. This requires adding the healpy library as skypy dependency.

Inputs

Catalogue of objects with RA, DEC, F

where F could be any property of the object (for example halo or galaxy) whose value are summed up for all objects that fall into the pixel.

For a galaxy count density map, F=1. For HI intensity maps, the density map is created by the HI mass of the object, F=M_HI.

Outputs

An Healpix array (i, p) where i is the index of the pixel and p the pixel value.

References