Parameters read by mult_alm:

infile (string):
  input file containing the a_lm

outfile (string):
  output file name for the calculated a_lm

fwhm_arcmin_in (real, default=0):
  FWHM (in arcmin) of a Gaussian beam, which will be _removed_ from the
  input a_lm

fwhm_arcmin_out (real, default=0):
  FWHM (in arcmin) of a Gaussian beam, which will be used to smoothe the
  output a_lm

pixwin_in (string, default=""):
  if supplied, the pixel window function from this file will be _removed_
  from the input a_lm

pixwin_out (string, default=""):
  if supplied, the pixel window function from this file will be applied
  to the output a_lm

cl_in (string, default=""):
  if supplied, the power spectrum from this file will be _removed_
  from the input a_lm
  NOTE: currently only supported for unpolarised a_lm

cl_out (string, default=""):
  if supplied, the power pectrum from this file will be applied
  to the output a_lm
  NOTE: currently only supported for unpolarised a_lm

polarisation (bool):
  if false, only the intensity a_lm are generated,
  if true, T, G and C a_lm are generated

double_precision (bool, default=false):
  if false, the a_lm are read/written in single precision,
  otherwise in double precision.
