nside2npix


Function to provide the number of pixels ${N_{\rm pix}}$ over the full sky corresponding to resolution parameter ${N_{\rm side}}$.

Location in HEALPix directory tree: src/f90/mod/pix_tools.F90 


FORMAT

var=nside2npix( nside )


ARGUMENTS

name & dimensionality kind in/out description
       
nside I4B IN the ${N_{\rm side}}$ parameter of the map.
var I8B OUT the number of pixels ${N_{\rm pix}}$ of the map. If ${N_{\rm side}}$ is valid (a power of 2 in $\{1,\ldots,2^{28}=268435456\}$), ${N_{\rm pix}}=12{N_{\rm side}}^2$ is returned; if not, an error message is issued and -1 is returned.


EXAMPLE:

use healpix_modules
integer(I8B) :: npix
npix= nside2npix(256)
Returns the number of HEALPix pixels (786432) for the resolution parameter 256.

RELATED ROUTINES

This section lists the routines related to nside2npix

npix2nside
returns resolution parameter corresponding to the number of pixels.

Version 3.31, 2017-01-06