renders the pixel number ipix (NESTED scheme) for a pixel which contains
a point on a sphere at coordinates theta and phi, given the map
resolution parametr nside
the computation is made to the highest resolution available (nside=8192)
and then degraded to that required (by integer division)
this doesn't cost more, and it makes sure
that the treatement of round-off will be consistent
for every resolution
renders the pixel number ipix (NESTED scheme) for a pixel which contains
a point on a sphere at coordinates theta and phi, given the map
resolution parametr nside
the computation is made to the highest resolution available (nside=8192)
and then degraded to that required (by integer division)
this doesn't cost more, and it makes sure
that the treatement of round-off will be consistent
for every resolution
renders the pixel number ipix (RING scheme) for a pixel which contains
a point on a sphere at coordinates theta and phi, given the map
resolution parametr nside
the computation is made to the highest resolution available (nside=8192)
and then degraded to that required (by integer division)
this doesn't cost more, and it makes sure
that the treatement of round-off will be consistent
for every resolution
renders the pixel number ipix (RING scheme) for a pixel which contains
a point on a sphere at coordinates theta and phi, given the map
resolution parametr nside
the computation is made to the highest resolution available (nside=8192)
and then degraded to that required (by integer division)
this doesn't cost more, and it makes sure
that the treatement of round-off will be consistent
for every resolution
returns the list of pixels in RING or NESTED scheme (listir);
with latitude in [phi0-dphi, phi0+dphi] on the ring ir;
(in {1,4*nside-1})
the pixel id-numbers are in {0,12*nside^2-1}
the indexing is RING, unless NEST is set to true;
======================================================================
Initialize pix2x and pix2y
constructs the array giving x and y in the face from pixel number
for the nested (quad-cube like) ordering of pixels
the bits corresponding to x and y are interleaved in the pixel number
one breaks up the pixel number by even and odd bits
Initialize pix2x and pix2y
constructs the array giving x and y in the face from pixel number
for the nested (quad-cube like) ordering of pixels
the bits corresponding to x and y are interleaved in the pixel number
one breaks up the pixel number by even and odd bits
Convert from pix number to angle
renders theta and phi coordinates of the nominal pixel center
for the pixel number ipix (NESTED scheme)
given the map resolution parameter nside
Convert from pix number to angle
renders theta and phi coordinates of the nominal pixel center
for the pixel number ipix (NESTED scheme)
given the map resolution parameter nside
Convert from pix number to angle
renders theta and phi coordinates of the nominal pixel center
for the pixel number ipix (RING scheme)
given the map resolution parameter nside
Convert from pix number to angle
renders theta and phi coordinates of the nominal pixel center
for the pixel number ipix (RING scheme)
given the map resolution parameter nside
=======================================================================;
query_disc (Nside, Vector0, Radius, Listpix, Nlist[, Nest, Inclusive]);
----------;
routine for pixel query in the RING or NESTED scheme;
all pixels within an angular distance Radius of the center;
Nside = resolution parameter (a power of 2);
Vector0 = central point vector position (x,y,z in double precision);
Radius = angular radius in RADIAN (in double precision);
Listpix = list of pixel closer to the center (angular distance) than Radius;
Nlist = number of pixels in the list;
nest (OPT), :0 by default, the output list is in RING scheme;
if set to 1, the output list is in NESTED scheme;
inclusive (OPT) , :0 by default, only the pixels whose center;
lie in the triangle are listed on output;
if set to 1, all pixels overlapping the triangle are output;
all pixel numbers are in {0, 12*Nside*Nside - 1}
NB : the dimension of the listpix array is fixed in the ing;
routine and should be large enough for the specific configuration;
lower level public void s ed by getdisc_ring :;
(you don't need to know them);
ring_num (nside, ir);
--------;
in_ring(nside, iz, phi0, dphi, listir, nir, nest=nest);
-------;
v1.0, EH, TAC, ??;
v1.1, EH, Caltech, Dec-2001;
=======================================================================
====================================================================
returns the ring number in {1, 4*nside-1}
from the z coordinate;
=====================================================================