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/C/subs/chealpix.c 


FORMAT

long nside2npix(const long nside)


ARGUMENTS

name&dimensionality kind in/out description
       
nside long IN the ${N_{\rm side}}$ parameter of the map.
nside2npix long OUT returns the number of pixels ${N_{\rm pix}}$ of the map ${N_{\rm pix}}=12{N_{\rm side}}^2$.


EXAMPLE:

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

ang2vec
converts $(\theta,\phi) $ spherical coordinates into (x,y,z) cartesian coordinates.
vec2ang
converts (x,y,z) cartesian coordinates into $(\theta,\phi) $ spherical coordinates.
npix2nside
converts ${N_{\rm side}}$ into number of full sky pixels ${N_{\rm pix}}$.

Version 3.30, 2015-10-08