pix2xxx, ang2xxx, nest2ring, ring2nest
Note: These routines are based on the translation of the original F77 routines to C++ and then to C, by Reza Ansari (ansari@lal.in2p3.fr), Alex Kim (akim@lilys.lbl.gov), Guy Le Meur (lemeur@lal.in2p3.fr), Benoit Revenu (revenu@iap.fr) and Ken Ganga (kmg@ipac.caltech.edu).
name&dimensionality | type | in/out | description |
---|---|---|---|
nside | long | IN | Nside parameter for the HEALPix map. |
ipnest | long | -- | pixel identification number in NESTED scheme over the range {0,Npix - 1}. |
ipring | long | -- | pixel identification number in RING scheme over the range {0,Npix - 1}. |
theta | double | -- | colatitude in radians measured southward from north pole in {0,![]() |
phi | double | -- | longitude in radians, measured eastward in {0,2![]() |
ROUTINES:
void pix2ang_ring(long nside, long ipring, double *theta, double *phi);
renders theta and phi coordinates of the nominal pixel center given the pixel number ipring and a map resolution parameter nside. |
void ang2pix_ring(long nside, double theta, double phi, long *ipring);
renders the pixel number ipring for a pixel which, given the map resolution parameter nside, contains the point on the sphere at angular coordinates theta and phi. |
void pix2ang_nest(long nside, long ipnest, double *theta, double *phi);
renders theta and phi coordinates of the nominal pixel center given the pixel number ipnest and a map resolution parameter nside. |
void ang2pix_nest(long nside, double theta, double phi, long *ipnest);
renders the pixel number ipnest for a pixel which, given the map resolution parameter nside, contains the point on the sphere at angular coordinates theta and phi. |
void nest2ring(long nside, long ipnest, long *ipring);
performs conversion from NESTED to RING pixel number. |
performs conversion from RING to NESTED pixel number. |
Eric Hivon 2003-02-07