remove_dipole
This IDL facility provides a means to fit and remove the dipole and monopole
from a HEALPix map.
Location in HEALPix directory tree: src/idl/misc/remove_dipole.pro
FORMAT
QUALIFIERS
-
Map
- input and output, vector
map from which monopole and dipole are to be removed
(also used for output).
Assumed to be a full sky data set, unless PIXEL is set and has the same
size as map
-
Weight
- input, vector, optional
same size as map,
describe weighting scheme to apply to each pixel for the fit
default:uniform weight
-
BAD_DATA =
-
scalar float, value given on input to bad pixels
default:!healpix.bad_value
.
-
GAL_CUT=
-
if set to a value larger than 0, the pixels with galactic
latitude |b|<gal_cut degrees are not considered in the
fit.
NB:
the cut is really done in Galactic coordinates. If the input
coordinates are different (see Coord_In), the map is rotated into galactic
before applying the cut.
-
COORD_IN =
-
string, map coordinate system (either 'Q' or 'C': equatorial,
'G': galactic or 'E': ecliptic; upper/lower case accepted)
default:'G' (galactic)
-
COORD_OUT =
-
string, coordinate system (see above) in which
to output dipole vector in variable Dipole
default:same as coord_in
-
Covariance_Matrix =
-
OUTPUT, scalar (or symmetric 4x4 matrix),
covariance
of the statistical errors made on monopole (and dipole) determination
-
Dipole=
-
OUTPUT, 3d vector,
coordinates of best fit dipole (done simultaneously with monopole), same
units as input map
-
Monopole=
-
OUTPUT, scalar float,
value found for the best fit monopole (done simultaneously with dipole),
same units as input map
-
NSIDE=
-
scalar integer, healpix resolution parameter
-
ORDERING=
-
string, ordering scheme (either 'RING' or 'NESTED')
-
PIXEL=
-
input, vector, gives the Healpix index of the pixels
whose temperature is actually given in map (for cut sky
maps). If present, must match Map in size. If absent, it is
assumed that the map covers the whole sky.
-
UNITS=
-
string, units of the input map
KEYWORDS
-
/NOREMOVE
-
if set, the best fit dipole and monopole are computed but not
removed (ie, Map is unchanged)
-
/ONLYMONOPOLE
-
if set, fit (and remove) only the monopole
-
/HELP
-
if set, only display documentation header
-
/SILENT
-
if set, the routine works silently
DESCRIPTION
remove_dipolemakes a simultaneous least square fit of the monopole and dipole on all the valid
pixels of Map (those with a value different from BAD_DATA) with a galactic
latitude larger in magnitude than GAL_CUT (in degrees). The position of the pixels
on the sky is reconstructed from NSIDE and ORDERING.
If Map does not cover the full sky, the actual indices of the concerned pixels should be given in PIXEL
RELATED ROUTINES
This section lists the routines related to remove_dipole
-
idl
- version 6.4 or more is necessary to run remove_dipole.
Version 3.83, 2024-11-13