HEALPix is an acronym for Hierarchical Equal Area isoLatitude Pixelation of a sphereThe HEALPix software is available in C, C++, Fortran90, IDL, Java and Python. In each of these languages are available an extensive library of HEALPix specific tools
and their supporting routines as well as a suite of programs implementing the key features of HEALPix. Each package allows all of, or most of, the following (and more):
1. Spherical Harmonics Transforms:
- Fast simulation and analysis of full-sky maps of CMB temperature and polarization anisotropy (sky maps preview) up to sub-arcminute angular resolution
- Filtering of sky maps with arbitrary circular window
- Constrained and non-Gaussian realization facilities
- Highly optimised Spherical Harmonics Transforms library (libsharp) used by all implementations for better performance
- Forward and backward scalar and spin-weighted Spherical Harmonics Transforms
- Programs to manage, modify and rotate spherical harmonic coefficients of arbitrary maps
2. Pixel manipulation:
- Pixelation of the sphere supported down to a pixel size of 0.4 mas (milli-arcseconds), corresponding to potentially 3.5 1018 pixels on the sphere
- Pixel queries in discs, triangles, polygons and strips
- Programs to search the maps for pixel neighbours and extrema of a random field
- Median filtering of sky maps
- Mask processing facilities
- Support for multi resolution maps (aka, Multi Order Coverage maps or MOC)
3. General:
- Comprehensive documentation (PDF and HTML); web-based and email support
- Automated installation and build scripts
- Most critical routines are parallelized
4. Visualization:
- Visualization facilities available in C++, Fortran 90, IDL, Java and Python
- Facilities to output HEALPix maps into Google Earth/Google Sky compliant images and into DomeMaster format used in planetariums.
5. Input/Output:
- routines to manipulate and visualize the FITS files generally used for I/O