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/ I8B 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 $\{1,\ldots,2^{28}\}$), $N_{\mathrm{side}}=\sqrt{N_{\mathrm{pix}}/12}$ is returned; if not, an error message is issued and -1 is returned.


EXAMPLE:

use healpix_modules
integer(I4B) :: nside
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

Version 3.50, 2018-12-10