read_fits_cut4
This IDL facility reads a cut sky HEALPix map from a FITS file according to
the HEALPix convention. The format used for the
FITS file follows the one used for Boomerang98 and is adapted from
COBE/DMR. This routine can also be used to read polarized cut sky map, where
each Stokes parameter is stored in a different extension of the same FITS file.
Location in HEALPix directory tree: src/idl/fits/read_fits_cut4.pro
FORMAT
QUALIFIERS
-
File
- name of a FITS file in which the map is to be written
-
Pixel
- (OUT, LONG vector),
index of observed (or valid) pixels
-
Signal
- (OUT, FLOAT vector),
value of signal in each observed pixel
-
N_Obs
- (OUT, LONG or INT vector, Optional),
number of observation per pixel
-
Serror
- (OUT, FLOAT vector, Optional),
rms of signal in pixel. For white noise,
this is
KEYWORDS
-
EXTENSION=
- (IN, optional),
0 based number of extension to read. Extension 0 contains the
temperature information, while extensions 1 and 2 contain respectively the Q
and U Stokes parameters related information. default:0
-
HDR=
- (OUT, optional),
String array containing the primary header.
-
XHDR=
- (OUT, optional),
String array containing the extension header.
-
NSIDE=
- (OUT, optional),
returns on output the HEALPix resolution parameter, as read
from the FITS header. Set to -1 if not found
-
ORDERING=
- (OUT, optional),
returns on output the pixel ordering, as read from the FITS
header. Either 'RING' or 'NESTED' or ' ' (if not found).
-
COORDSYS=
- (OUT, optional),
returns on output the astrophysical coordinate system used,
as read from FITS header (value of keywords COORDSYS or SKYCOORD)
-
HELP=
- (IN, optional),
if set, an extensive help is displayed, and no file is read
DESCRIPTION
For more information on the FITS file format supported in HEALPix,
including the one implemented in read_fits_cut4 ,
see https://healpix.sourceforge.io/data/examples/healpix_fits_specs.pdf.
RELATED ROUTINES
This section lists the routines related to read_fits_cut4
-
idl
- version 6.4 or more is necessary to run read_fits_cut4
-
write_fits_cut4
- This HEALPix IDL
facility can be used to generate the FITS format cut-sky maps complient
with HEALPix convention and readable by read_fits_cut4 .
-
read_fits_cut4,
read_fits_partial,
read_fits_map
-
read_tqu,
read_fits_s
- HEALPix IDL routines to read cut-sky maps and partial maps, full-sky maps, polarized full-sky maps and
arbitrary data sets from FITS files
-
sxpar
- This IDL routine (included in HEALPix package) can be
used to extract FITS keywords from the header(s) HDR or XHDR read with read_fits_cut4 .
Version 3.82, 2022-07-28