By default, files with the very same name will be looked for into: the current directory (.), the parent directory (..), ./data, ../data, $HEALPIX and $HEALPIX/data where $HEALPIX is a system variable defined as the full path to the HEALPix package (see the installation documentation). The user has the possibility to change both the name of those files and their location.
Eric Hivon 2003-02-07