ismoothing


This IDL facility provides an interface to F90 'smoothing' facility. It can be used to smooth a HEALPix map by an arbitrary circular 'beam' defined by its Legendre window function (or its FWHM if it is assumed Gaussian)

Location in HEALPix directory tree: src/idl/interfaces/ismoothing.pro 


FORMAT

IDL> ISMOOTHING, map1_in, map2_out,[ beam_file=, binpath=, /double, fwhm_arcmin=, /help, iter_order=, keep_tmp_files=, lmax=, nlmax=, /nested, ordering=, plmfile=, regression=, /ring, simul_type=, /silent, theta_cut_deg=, tmpdir=, /won, w8file=, w8dir=]


QUALIFIERS

map1_in
required input: input map, can be a FITS file, or a memory array containing the map to smooth
map2_out
required output: output smoothed map, can be a FITS file, or a memory array


KEYWORDS

beam_file=
beam window function, either a FITS file or an array

binpath=
full path to back-end routine default:$HEXE/smoothing, then $HEALPIX/bin/smoothing
- a binpath starting with / (or $\backslash$),   or $ is interpreted as absolute
- a binpath starting with ./ is interpreted as relative to current directory
- all other binpathes are relative to $HEALPIX

/double
if set, I/O is done in double precision default:single precision I/O

fwhm_arcmin=
gaussian beam Full Width Half Maximum in arc-minutes default:0

/help
if set, prints extended help

iter_order=
order of iteration in the analysis default:0

/keep_tmp_files
if set, temporary files are not discarded at the end of the run

lmax=, nlmax=
maximum multipole of smoothing default:determined by back-end routine (ie, smoothing)

/nested
if set, signals that *all* maps and mask read online are in NESTED scheme (does not apply to FITS file), /ring and Ordering

ordering=
either 'RING' or 'NESTED', ordering of online maps and masks, see /ring and /nested

plmfile=
FITS file containing precomputed Spherical Harmonics (deprecated) default:no file

regression=
0, 1 or 2, regress out best fit monopole and/or dipole before alm analysis default:0, analyze raw map

/ring
see /nested and Ordering above

simul_type=
1 or 2, analyze temperature only or temperature + polarization

/silent
if set, works silently

theta_cut_deg=
cut around the equatorial plane

tmpdir=
directory in which are written temporary files default:IDL_TMPDIR (see IDL documentation)

/won
if set, a weighting scheme is used to improve the quadrature default:apply weighting

w8file=
FITS file containing weights default:determined automatically by back-end routine. Do not set this keyword unless you really know what you are doing

w8dir=
directory where the weights are to be found default:determined automatically by back-end routine


DESCRIPTION

ismoothing is an interface to 'smoothing' F90 facility. It requires some disk space on which to write the parameter file and the other temporary files. Most data can be provided/generated as an external FITS file, or as a memory array.


RELATED ROUTINES

This section lists the routines related to ismoothing

idl
version 6.4 or more is necessary to run ismoothing.
smoothing
F90 facility called by ismoothing.
beam2bl
This IDL facility computes a transfer (or window) function b(l) (such as the ones required by ismoothing) for a given circular beam profile $b(\theta)$
ialteralm
IDL Interface to F90 alteralm
ianafast
IDL Interface to F90 anafast and C++ anafast_cxx
iprocess_mask
IDL Interface to F90 process_mask
isynfast
IDL Interface to F90 synfast


EXAMPLE:

whitenoise = randomn(seed, nside2npix(256))
ismoothing, whitenoise, rednoise, fwhm=120, /ring, simul=1,/silent
mollview, whitenoise,title='White noise'
mollview, rednoise, title='Smoothed white Noise'
will generate and plot a white noise map and its smoothed version

Version 3.31, 2017-01-06