read_par

This routine reads the `NSIDE', `TFIELDS' , `MAX-LPOL', and optionally `MAX-MPOL' keywords from a FITS-file. These keywords desribe $N_{\mathrm{side}}$, number of datasets (maps) and maximum multipole $\ell$ (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 $a_{\ell m}$ or precomputed $P_{\ell m}(\theta)$

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 $N_{\mathrm{side}}$ and maximum $\ell$ value used for the precomputed $P_{\ell m}(\theta)$ 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.