nest2uniq


This F90 facility turns the parameter ${N_{\rm side}}$ (a power of 2) and the pixel index p into the Unique ID number $u = p + 4 {N_{\rm side}}^2$. See ''The Unique Identifier scheme'' section in ''HEALPix Introduction Document'' for more details.

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


FORMAT

call nest2uniq( nside, pnest, puniq )


ARGUMENTS

name kind in/out description
       
nside I4B IN The HEALPix ${N_{\rm side}}$ parameter.
pnest I4B/I8B IN (NESTED scheme) pixel identification number over the range {0, $12{N_{\rm side}}^2-1$}.
puniq I4B/I8B OUT The HEALPix Unique pixel identifier.


EXAMPLE:

use healpix_modules
integer(I4B) :: puniq
call nest2uniq(1, 0, puniq)
print*,puniq
returns
4
since the first pixel (p=0) at ${N_{\rm side}}=$ 1 is the pixel with Unique ID number 4.


RELATED ROUTINES

This section lists the routines related to nest2uniq

uniq2nest
] Transforms Unique HEALPix pixel ID number into Nside and Nested pixel number
pix2xxx, ...
to turn NESTED pixel index into sky coordinates and back

Version 3.31, 2017-01-06