read_par


This routine reads the `NSIDE', `TFIELDS' , `MAX-LPOL', and optionally `MAX-MPOL' keywords from a FITS-file. These keywords desribe Nside, number of datasets (maps) and maximum multipole l (order) and m (degree) value for the file. If a keyword is not found in the FITS file, a value of -1 is returned instead. The file could eg. be a HEALPix map, or a set of alm or precomputed $P_{lm}(\theta)$

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


FORMAT

call read_par( filename, nside, lmax, tfields[, mmax] )


ARGUMENTS

name & dimensionality kind in/out description
       
filename(LEN=filenamelen) CHR IN filename of the FITS file.
nside I4B OUT `NSIDE' keyword value from the FITS header.
lmax I4B OUT `MAX-LPOL' keyword value from the FITS header.
tfields I4B OUT `TFIELDS' keyword value from the FITS header.
mmax (OPTIONAL) I4B OUT `MAX-MPOL' keyword value from the FITS header.


EXAMPLE:

call read_par('plm_128p.fits', nside, lmax, nhar)
Checks the Nside and maximum l value used for the precomputed $P_{lm}(\theta)$ that are stored in the file `plm_128p.fits'. If the file also contains tensor harmonics, nhar is returned with the value 3, otherwise it is 1.

MODULES & ROUTINES

This section lists the modules and routines used by read_par.

fitstools
module, containing:
printerror
routine for printing FITS error messages.
cfitsio
library for FITS file handling.


RELATED ROUTINES

This section lists the routines related to read_par

synfast, plmgen
executables that produce FITS-files with keywords relevant to this routine.

Version 3.31, 2017-01-06