alm2map_der*
This routine is a wrapper to four other routines that synthesize a HEALPix
temperature (and polarisation) map(s), its (their) first derivatives, and optionally
its (their) second derivatives.
The routines accept both single and double precision arrays for alm, map, der1 and
der2. The precision of these arrays should match. All maps produced are RING
ordered.
See ”Fortran
Facilities”
Appendix for a note on a bug
affecting the calculation of polarisation derivatives on past versions of this routine.
Location in HEALPix directory tree: src/f90/mod/alm_tools.F90
FORMAT
ARGUMENTS
name & dimensionality |
kind |
in/out |
description |
|
|
|
|
nsmax |
I4B |
IN |
the
value of the map to synthesize. |
nlmax |
I4B |
IN |
the maximum value used for the
. |
nmmax |
I4B |
IN |
the maximum value used for the
. |
alm(1:p, 0:nlmax, 0:nmmax) |
SPC/ DPC |
IN |
The
values to make the map
from. p is either 1 (temperature only) or 3 (temperature+polarisation). |
map(0:12*nsmax**2-1) or (0:12*nsmax**2-1,1:3) |
SP/ DP |
OUT |
temperature
map or temperature + polarisation maps , , to be synthesized. |
der1(0:12*nsmax**2-1, 1:2*p) |
SP/ DP |
OUT |
contains on output the first
derivatives of T:
or the interleaved derivatives of T, Q, and U:
|
der2(0:12*nsmax**2-1,1:3*p), OPTIONAL |
SP/ DP |
OUT |
If this optional
matrix is passed with this rank, it will contain on output the second derivatives
or
|
zbounds(1:2), OPTIONAL |
DP |
IN |
section of the sphere on which to perform the map synthesis, expressed in terms of
If zbounds(1)zbounds(2), it is
performed on the strip zbounds(1)zbounds(2); if not,
it is performed outside the strip
zbounds(2)zbounds(1). If absent, the whole map is processed.
|
EXAMPLE:
use healpix_types
use pix_tools, only : nside2npix
use alm_tools, only : alm2map_der
integer(I4B) :: nside, lmax, mmax, npix
real(SP), dimension(:), allocatable :: map
real(SP), dimension(:,:), allocatable :: der1, der2
complex(SPC), dimension(:,:,:), allocatable :: alm
...
nside=256 ; lmax=512 ; mmax=lmax
npix=nside2npix(nside)
allocate(alm(1:1,0:lmax,0:mmax))
allocate(map(0:npix-1))
allocate(der1(0:npix-1,1:2), der2(0:npix-1,1:3))
...
call alm2map_der(nside, lmax, mmax, alm, map, der1, der2=der2)
Make temperature maps and its derivatives from the
passed in alm. The maps have
of 256, and are constructed from
values up to 512 in and .
MODULES & ROUTINES
This section lists the modules and routines used by alm2map_der*.
-
ring_synthesis
- Performs FFT over for synthesis of the rings.
-
compute_lam_mm, get_pixel_layout,
-
gen_lamfac_der, gen_mfac,
-
gen_recfac, init_rescale, l_min_ylm
- Ancillary routines used
for
recursion
-
misc_utils
- module, containing:
-
assert_alloc
- routine to print error message, when an array can not be
allocated properly
RELATED ROUTINES
This section lists the routines related to alm2map_der*
-
alm2map
- routine generating maps of temperature
and polarisation from their
-
alm2map_spin
- routine generating maps of
arbitrary spin from their
-
synfast
- executable using alm2map_der* to synthesize maps.
-
create_alm
- routine to generate randomly
distributed
coefficients according to a given power spectrum
Version 3.82, 2022-07-28