Installation Requirements

The major part of the HEALPix distribution is written in Fortran 90 and so the appropriate compiler must be present (Linux and Darwin users should look at Section 7). Many visualisation tools and map manipulation routines are provided in IDL (please note that at least version 5.0 is required). Some of the HEALPix routines are now also available in C (for further details on these routines and there installation, please report to the document ''C Subroutines Overview''). The configure script is written in the Bourne shell. The script attempts to generate a Makefile which is tailored to one of the above Operating Systems (OS's) and using Makefile.in as a template for non-system specific statements. Only the basic UNIX make facility is required to build the software, although we do still recommend the GNU make facility (ftp://ftp.gnu.org/gnu/make/). In addition, a system Profile and IDL startup file are generated/included in the distribution. These automatically establish various environment variables and aliases to make the use of the HEALPix package simpler.

The HEALPix Fortran 90 and C distributions also require the publicly available CFTISIO library:

Software Package Source
   
CFITSIO V 2.xx library http://heasarc.gsfc.nasa.gov/docs/software/fitsio/
   
 

The user may choose to link HEALPix with the publicly available FFTW library

Software Package Source
   
FFTW V 2.1.3 library http://www.fftw.org/index.html
   
 

If not, a FFT module is shipped with HEALPix and will be used by default.

And finally, the IDL visualization software is commercially available at

Software Package Source
   
IDL V 5.x http://www.rsinc.com/
   
 

(versions 5.3 to 5.5 have been extensively used during the development of the HEALPix IDL codes).

As it was already the case in version 1.10, users no longer need to acquire The IDL Astronomy User's Library (http://idlastro.gsfc.nasa.gov/homepage.html) or the COBE (IDL) Analysis Software (http://www.gsfc.nasa.gov/astro/cobe/cgis.html), although we do recommend these packages to the user. The few routines required for version 1.20 are contained in a new subdirectory Healpix_1.20/src/idl/zzz_external. These procedures are included in the HEALPix package unchanged and solely for the purpose of making it self contained. In this way, we remove the burden of installation of additional libraries from the end user.

At the user choice (at installation time) the FFT operations can be performed with the FFT code shipped with the package, or with the freely available FFTW. In the latter case FFTW should be compiled in double precision.

A parallel implementation (based on Open MP) of the Spherical Harmonics Transforms involved in synfast, anafast, smoothing and plmgen is now available, thanks to the work of Stéphane Colombi. It has only been tested on SGI and DEC computers. At this point, it can not be used together with FFTW.

We found that it was remarkably difficult to find random number generators in the public domain which are simple yet powerful and easy to use. One of us (BDW) has therefore attempted to create one and we provide it as free software with this package (cf. Appendix I).

Eric Hivon 2003-02-07