healpixNestToRing( k, nestIndex )Note: the nestIndex parameter is 0-based,
unlike the table row index special token $index
(a.k.a. $0), which is 1-based.
So if the HEALpix index is implicitly determined by the table row,
the value $index-1 should be used.
k (integer)nestIndex (long integer)long healpixNestToRing(int, long)