nest2uniq

This F90 facility turns the parameter $N_{\mathrm{side}}$ (a power of 2) and the pixel index $p$ into the Unique ID number $u = p + 4 N_{\mathrm{side}}^2$. 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 $N_{\mathrm{side}}$ parameter.
pnest I4B/I8B IN (NESTED scheme) pixel identification number over the range {0, $12N_{\mathrm{side}}^2-1$}.
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 $N_{\mathrm{side}}=$ 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 3.82, 2022-07-28