unfold_weightsfile

This routine read a ring-based or pixel-based quadrature weight file and turn it into a full sky (ring-ordered) HEALPix map.

Location in HEALPix directory tree: src/f90/mod/fitstools.F90 

FORMAT

call unfold_weightsfile( w8file, w8map )

ARGUMENTS

name & dimensionality	kind	in/out	description
w8file(LEN=filenamelen)	CHR	IN	filename of FITS-file containing a list of ring-ordered or pixel-ordered quadrature weights for some Nside.
w8map(0:12*Nside**2-1)	SP/ DP	OUT	an array containing a full sky map of weights for the same Nside.

EXAMPLE:

use healpix_modules
real(DP), allocatable(:) :: w8map
character(len=FILENAMELEN) :: dirname, filename
integer(I4B) :: nside, won
won = 2
nside = 128
npix = nside2npix(nside)
allocate(w8map(0:npix-1))
dirname = get_healpix_data_dir()
filename = get_healpix_weights_file(nside, won)
filename = trim(dirname)//'/'//trim(filename)
call unfold_weightsfile(filename, w8map)

This code snippet looks for a pixel-based (won=2) weights file in standard location, with a standard name, for nside=128, reads it and unfolds it into a full sky ring-ordered map named w8map.

MODULES & ROUTINES

This section lists the modules and routines used by unfold_weightsfile.

pixtools

module, containing:

nside2npweights

function returning the number of pixel-based weights expected for a given Nside when stored in compact form

nside2npix

function returning the number of pixels on the full sky, for a given Nside

fitstools

module, containing:

printerror

routine for printing FITS error messages.

getsize_fits

function returning the size of a FITS file, and parsing its header.

input_map

routine to read FITS file.

cfitsio

library for FITS file handling.

RELATED ROUTINES

This section lists the routines related to unfold_weightsfile

get_healpix_data_dir

routine returning actual path to data directory

get_healpix_weights_file

routine returning the standard name of pre-computed weights file

anafast, smoothing

these two facilities use unfold_weightsfile to apply quadrature weighting to the maps they respectively analyze and smooth