npix2nside


Function to provide the resolution parameter Nside correspoonding to Npix pixels over the full sky.


Location in HEALPix directory tree: src/f90/mod/pix_tools.f90


FORMAT

var=npix2nside( npix )


ARGUMENTS

name&dimensionality kind in/out description
       
npix I4B IN the number Npix of pixels over the whole sky.
var I4B OUT the parameter Nside. If Npix is valid (12 times a power of 2 in {1,..., 8192}), Nside = $ \sqrt{(}$Npix/12) is returned; if not, an error message is issued and -1 is returned.


EXAMPLE:

nside= npix2nside(786432)

Returns the resolution parameter Nside (256) corresponding to 786432 pixels on the sky.

RELATED ROUTINES

This section lists the routines related to npix2nside


nside2npix
returns the number of pixels Npix correspondinng to resolution parameter Nside

Eric Hivon 2003-02-07