read_dbintab


This routine reads a double precision binary array from a FITS-file. It is used by HEALPix to read precomputed $P_{lm}(\theta)$ values and pixel window functions.

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


FORMAT

call read_dbintab( filename, map, npixtot, nmaps, nullval, anynull, units )


ARGUMENTS

name & dimensionality kind in/out description
       
filename(LEN=filenamelen) CHR IN filename of FITS-file containing the double precision array.
npixtot I4B IN Number of values to be read from the file.
nmaps I4B IN number of 1-dim. arrays, 1 for scalar $P_{lm}\!\!$ s and pixel windows, 3 for scalar and tensor $P_{lm}\!\!$ s.
map(0:npixtot-1,1:nmaps) DP OUT the array read from the FITS-file.
nullval DP OUT value of missing pixels in the array.
anynull LGT OUT TRUE, if there are missing pixels, and FALSE otherwise.
units(len=20)(1:nmaps) CHR OUT respective physical units of the maps in the FITS file.


EXAMPLE:

call read_dbintab ('plm_32.fits',plm,65*66*32,1,nullval,anynull)
Reads precomputed scalar $P_{lm}(\theta)$ from the file `plm_32.fits'. The values are returned in the array plm(0:65*66*32,1:1). The number of values 65*66*32 is the number of precomputed $P_{lm}(\theta)$ for a Nside=32, lmax=64 map. If there are missing values in the file, anynull is TRUE and nullval contains the values of these pixels.


MODULES & ROUTINES

This section lists the modules and routines used by read_dbintab.

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_dbintab

plmgen
Executable to create files with precomputed $P_{lm}(\theta)$.
write_plm
Routine to create a file to be read by read_dbintab.

Version 3.31, 2017-01-06