Module s2_cmb_mod

module s2_cmb_mod

        ! Uses
    use s2_types_mod
    use s2_error_mod
    use s2_distn_mod
    use s2_pl_mod
    use s2_sky_mod
    use s2_wnoise_mod

        ! Types
    public type s2_cmb

        ! Interfaces
    public interface s2_cmb_init

        ! Subroutines and functions
    private function s2_cmb_init_pl (clt, nside, seed, beam, compute_map) result (cmb)
    private function s2_cmb_init_array (clt_spec, nside, seed, beam, compute_map) result (cmb)
    private function s2_cmb_init_file (filename_clt, nside, lmin, lmax, ncomment, seed, beam, scale_cl, compute_map) result (cmb)
    private function s2_cmb_init_copy (orig) result (copy)
    public subroutine s2_cmb_free (cmb)
    public subroutine s2_cmb_gen_sky (cmb, seed, beam, compute_map)
    private subroutine s2_cmb_apply_beam (cmb, beam)
    private subroutine s2_cmb_create_alm (cmb, seed_in)
    private subroutine s2_cmb_compute_map (cmb)
    public subroutine s2_cmb_map_convert (cmb, pix_scheme)
    public subroutine s2_cmb_add_noise (cmb, wnoise)
    public subroutine s2_cmb_write_sky (cmb, filename, comment)
    public function s2_cmb_get_init (cmb) result (init)
    public function s2_cmb_get_nside (cmb) result (nside)
    public function s2_cmb_get_npix (cmb) result (npix)
    public function s2_cmb_get_lmax (cmb) result (lmax)
    public function s2_cmb_get_sky (cmb) result (sky)
    public function s2_cmb_get_clt (cmb) result (clt)
    public function s2_cmb_get_noise_added (cmb) result (noise_added)
    public function s2_cmb_get_beam_applied (cmb) result (beam_applied)

end module s2_cmb_mod

Provides functionality to create a Gaussian simuated CMB map. The map is realised from Gaussain alms that satisfy the specified CMB power spectrum.

Author: J. D. McEwen (mcewen@mrao.cam.ac.uk)

Version: 0.1 August 2004

Description of Types

s2_cmb

public type s2_cmb
    private
    logical :: init = .false.
    integer :: seed
    integer :: nside = 0
    type (s2_sky) :: sky
    type (s2_pl) :: clt
    logical :: noise_added = .false.
    logical :: beam_applied = .false.
end type s2_cmb

Description of Interfaces

s2_cmb_init

public interface s2_cmb_init
    module procedure s2_cmb_init_pl
    module procedure s2_cmb_init_array
    module procedure s2_cmb_init_file
    module procedure s2_cmb_init_copy
end interface s2_cmb_init

Description of Subroutines and Functions

s2_cmb_init_pl

private function s2_cmb_init_pl (clt, nside, seed, beam, compute_map) result (cmb)
    type (s2_pl), intent(in) :: clt
    integer, intent(in) :: nside
    integer, intent(in) :: seed
    type (s2_pl), optional, intent(in) :: beam
    logical, optional, intent(in) :: compute_map
    type (s2_cmb) :: cmb
    ! Calls: s2_cmb_gen_sky, s2_error
end function s2_cmb_init_pl

Initialise a Gaussian cmb form a clt spectrum pl object. If beam is present then the realised cmb alms are convolved with the beam before the cmb map is generated.

Variables:

clt: Clt spectrum that fully defines the statistical characteristics of a cmb realisation as a pl object.
nside: Sky Healpix resolution.
seed: Seed for generating samples from a Gaussian distribution.
[beam]: If present then the amb alms are convolved with this beam before a map representation is constructed.
[compute_map]: Logical to specify whether to compute the cmb map from the alms (default is true).
cmb: Cmb initialised.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_init_array

private function s2_cmb_init_array (clt_spec, nside, seed, beam, compute_map) result (cmb)
    real (kind=s2_sp), intent(in), dimension (:) :: clt_spec
    integer, intent(in) :: nside
    integer, intent(in) :: seed
    type (s2_pl), optional, intent(in) :: beam
    logical, optional, intent(in) :: compute_map
    type (s2_cmb) :: cmb
    ! Calls: s2_cmb_gen_sky, s2_error
end function s2_cmb_init_array

Initialise a Gaussian cmb form a clt spectrum array. If beam is present then the realised cmb alms are convolved with the beam before the cmb map is generated.

Variables:

clt_spec: Clt spectrum that fully defines the statistical characteristics of a cmb realisation.
nside: Sky Healpix resolution.
seed: Seed for generating samples from a Gaussian distribution.
[beam]: If present then the amb alms are convolved with this beam before a map representation is constructed.
[compute_map]: Logical to specify whether to compute the cmb map from the alms (default is true).
cmb: Cmb initialised.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_init_file

private function s2_cmb_init_file (filename_clt, nside, lmin, lmax, ncomment, seed, beam, scale_cl, compute_map) result (cmb)
    character (len=*), intent(in) :: filename_clt
    integer, intent(in) :: nside
    integer, intent(in) :: lmin
    integer, intent(in) :: lmax
    integer, intent(in) :: ncomment
    integer, intent(in) :: seed
    type (s2_pl), optional, intent(in) :: beam
    logical, optional, intent(in) :: scale_cl
    logical, optional, intent(in) :: compute_map
    type (s2_cmb) :: cmb
    ! Calls: s2_cmb_gen_sky, s2_error
end function s2_cmb_init_file

Initialise a Gaussian cmb from a file containing a clt spectrum. If beam is present then the realised cmb alms are convolved with the beam before the cmb map is generated.

Variables:

filename_clt: Name of the file containing the clt spectrum.
nside: Sky Healpix resolution.
lmin: Minimum l value read from file. (The first value read will be saved a this l. Clt for all lower values of l is set to zero. Typically lmin=2 so monopole and dipole not included.)
lmax: Maximum l value of clt.
ncomment: Number of comment lines in file to ignore before start reading clt values.
seed: Seed for generating samples from a Gaussian distribution.
[beam]: If present then the amb alms are convolved with this beam before a map representation is constructed.
[compute_map]: Logical to specify whether to compute the cmb map from the alms (default is true).
cmb: Cmb initialised.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_init_copy

private function s2_cmb_init_copy (orig) result (copy)
    type (s2_cmb), intent(in) :: orig
    type (s2_cmb) :: copy
    ! Calls: s2_error
end function s2_cmb_init_copy

Initialise a cmb from a copy of an original cmb.

Variables:

orig: Original cmb to be copied.
copy: Initialised cmb with attributes copied from orig.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_free

public subroutine s2_cmb_free (cmb)
    type (s2_cmb), intent(inout) :: cmb
    ! Calls: s2_error, s2_pl_free, s2_sky_free
end subroutine s2_cmb_free

Free all data associated with an initialised cmb and reset all other attributes. Variables:

cmb: Cmb to be freed.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_gen_sky

public subroutine s2_cmb_gen_sky (cmb, seed, beam, compute_map)
    type (s2_cmb), intent(inout) :: cmb
    integer, optional, intent(in) :: seed
    type (s2_pl), optional, intent(in) :: beam
    logical, optional, intent(in) :: compute_map
    ! Calls: s2_cmb_apply_beam, s2_cmb_compute_map, s2_cmb_create_alm, s2_error
end subroutine s2_cmb_gen_sky

Generate a sky realisation of the cmb from the clt spectrum. First Gaussian alm values that satisfy the clt spectrum are generated, these are convolved with a beam (if present), before the map realisation is computed from an inverse spherical harmonic transform.

Notes:

Object must be initialised before this routine is call. If to be called from init function then must set init status first.
Map is converted here to have units of mK. -- Not any more!

Variables:

cmb: Cmb to generate sky map of.
[seed]: Seed for sampling Gaussian distribution. If not present the cmb seed attribute will be used.
[beam]: Beam function. No beam is convolved if not present.
[compute_map]: Logical to specify whether to compute the cmb map from the alms (default is true).

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_apply_beam

private subroutine s2_cmb_apply_beam (cmb, beam)
    type (s2_cmb), intent(inout) :: cmb
    type (s2_pl), intent(in) :: beam
    ! Calls: s2_error, s2_pl_conv, s2_sky_free, s2_sky_get_alm
end subroutine s2_cmb_apply_beam

Convolve beam with cmb alms. The cmb alms are overwritten with the convolved alms.

Variables:

cmb: Cmb to apply beam to.
beam: Beam to apply.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_create_alm

private subroutine s2_cmb_create_alm (cmb, seed_in)
    type (s2_cmb), intent(inout) :: cmb
    integer, optional, intent(in) :: seed_in
    ! Calls: s2_error, s2_sky_free
end subroutine s2_cmb_create_alm

Create Gaussian cmb alms that satify the clt spectrum.

Variables:

cmb: Cmb to create alms for.
[seed_in]: Seed to generate samples from a Gaussian distribution. If not present then the cmb seed attribute is used.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_compute_map

private subroutine s2_cmb_compute_map (cmb)
    type (s2_cmb), intent(inout) :: cmb
    ! Calls: s2_error, s2_sky_compute_map
end subroutine s2_cmb_compute_map

Compute the cmb sky map from alms.

Variables:

cmb: Cmb to compute map of.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_map_convert

public subroutine s2_cmb_map_convert (cmb, pix_scheme)
    type (s2_cmb), intent(inout) :: cmb
    integer, intent(in) :: pix_scheme
    ! Calls: s2_error, s2_sky_map_convert
end subroutine s2_cmb_map_convert

Convert sky map pixelisation scheme between nested and ring.

Variables:

cmb: Cmb to convert pixelisation scheme of.
pix_scheme: Pixelisation scheme to convert to.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_add_noise

public subroutine s2_cmb_add_noise (cmb, wnoise)
    type (s2_cmb), intent(inout) :: cmb
    type (s2_wnoise), intent(in) :: wnoise
    ! Calls: s2_error, s2_sky_free
end subroutine s2_cmb_add_noise

Add noise to the cmb sky map. The cmb noise_added attribute flag is also set.

Notes:

When noise is added to the cmb sky, the old sky is overwritten with the new one (the sum of the old one and the noise sky). Since the old alms correspond only to the old simulated cmb map, and not the map plus noise, they are wiped from the resultant sky saved.

Variables:

cmb: Cmb to add noise to.
wnoise: White noise object containing noise realisation to add to cmb sky map.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_write_sky

public subroutine s2_cmb_write_sky (cmb, filename, comment)
    type (s2_cmb), intent(in) :: cmb
    character (len=*), intent(in) :: filename
    character (len=*), optional, intent(in) :: comment
    ! Calls: s2_error, s2_sky_write_map_file
end subroutine s2_cmb_write_sky

Write the cmb sky to an output fits file.

Variables:

cmb: Cmb to be written to a fits file.
filename: Name of the outout fits file.
[comment]: Optional comment to add to header of output file.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_init

public function s2_cmb_get_init (cmb) result (init)
    type (s2_cmb), intent(in) :: cmb
    logical :: init
end function s2_cmb_get_init

Get init variable from the passed cmb.

Variables:

cmb: Cmb object to get the variable of.
init: Object init variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_nside

public function s2_cmb_get_nside (cmb) result (nside)
    type (s2_cmb), intent(in) :: cmb
    integer :: nside
    ! Calls: s2_error
end function s2_cmb_get_nside

Get nside variable from the passed cmb.

Variables:

cmb: Cmb object to get the variable of.
nside: Object nside variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_npix

public function s2_cmb_get_npix (cmb) result (npix)
    type (s2_cmb), intent(in) :: cmb
    integer :: npix
    ! Calls: s2_error
end function s2_cmb_get_npix

Get npix variable from the passed cmb.

Variables:

cmb: Cmb object to get the variable of.
npix: Object npix variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_lmax

public function s2_cmb_get_lmax (cmb) result (lmax)
    type (s2_cmb), intent(in) :: cmb
    integer :: lmax
    ! Calls: s2_error
end function s2_cmb_get_lmax

Get lmax variable from the passed cmb.

Variables:

cmb: Cmb object to get the variable of.
lmax: Object lmax variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_sky

public function s2_cmb_get_sky (cmb) result (sky)
    type (s2_cmb), intent(in) :: cmb
    type (s2_sky) :: sky
    ! Calls: s2_error
end function s2_cmb_get_sky

Get sky variable from the passed cmb.

Notes:

Initialises a new sky as a copy of the cmb sky.
The returned sky is subsequently independed of the sky stored herein and should be freed by the calling routine at some point.

Variables:

cmb: Cmb object to get the variable of.
sky: Object sky variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_clt

public function s2_cmb_get_clt (cmb) result (clt)
    type (s2_cmb), intent(in) :: cmb
    type (s2_pl) :: clt
    ! Calls: s2_error
end function s2_cmb_get_clt

Get clt variable from the passed cmb.

Notes:

Initialises a new clt as a copy of the cmb clt.
The returned clt is subsequently independed of the clt stored herein and should be freed by the calling routine at some point.

Variables:

cmb: Cmb object to get the variable of.
clt: Object clt variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_noise_added

public function s2_cmb_get_noise_added (cmb) result (noise_added)
    type (s2_cmb), intent(in) :: cmb
    logical :: noise_added
    ! Calls: s2_error
end function s2_cmb_get_noise_added

Get noise_added variable from the passed cmb.

Variables:

cmb: Cmb object to get the variable of.
noise_added: Object noise_added variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004

s2_cmb_get_beam_applied

public function s2_cmb_get_beam_applied (cmb) result (beam_applied)
    type (s2_cmb), intent(in) :: cmb
    logical :: beam_applied
    ! Calls: s2_error
end function s2_cmb_get_beam_applied

Get beam_applied variable from the passed cmb.

Variables:

cmb: Cmb object to get the variable of.
beam_applied: Object beam_applied variable returned.

Author: J. D. McEwen

Version: 0.1 August 2004