so_mcm - a module for mode coupling calculation

Routines for mode coupling calculation. For more details on computation of the matrix see https://pspy.readthedocs.io/en/latest/scientific_doc.pdf.

pspy.so_mcm.apply_Bbl(Bbl, ps, spectra=None)

Bin theoretical power spectra

Parameters:

• Bbl (2d array (or dict of 2d array)) – a binning matrix, if spectra is not None will be a Bbl dictionnary for spin0 and 2 fields, otherwise a (n_bins,lmax) matrix

• ps (1d array or dict of 1d array) – theory ps, if spectra is not None it will be a ps dictionnary, otherwise a (lmax) vector

• spectra (list of string) – needed for spin0 and spin2 cross correlation, the arrangement of the spectra

pspy.so_mcm.coupling_dict_to_array(dict)

Take a mcm or Bbl dictionnary with entries:

• (spin0xspin0), (spin0xspin2), (spin2xspin0), (spin2xspin2)

and return a 9 x dim1, 9 x dim2 array. dim1 and dim2 are the dimensions of the spin0 object

pspy.so_mcm.format_toepliz_fortran(coupling, l_toep, lmax)

Take a matrix and apply the toepliz appoximation (fortran)

Parameters:

• coupling (array) – consist of an array where the upper part is the exact matrix and the lower part is the diagonal. We will feed the off diagonal of the lower part using the measurement of the correlation from the exact computatio

• l_toep (integer) – the l at which we start the approx

• lmax (integer) – the maximum multipole of the array

pspy.so_mcm.format_toepliz_fortran2(coupling, l_toep, l_exact, lmax)

Take a matrix and apply the toepliz appoximation (fortran)

Parameters:

• coupling (array) – consist of an array where the upper part is the exact matrix and the lower part is the diagonal. We will feed the off diagonal of the lower part using the measurement of the correlation from the exact computatio

• l_toep (integer) – the l at which we start the approx

• l_exact (integer) – the l until which we do the exact computation

• lmax (integer) – the maximum multipole of the array

pspy.so_mcm.mcm_and_bbl_spin0(win1, binning_file, lmax, niter, type='Dl', win2=None, bl1=None, bl2=None, input_alm=False, binned_mcm=True, save_file=None, l_exact=None, l_toep=None, l_band=None, l3_pad=2000, return_coupling_only=False)

Get the mode coupling matrix and the binning matrix for spin0 fields

Parameters:

• win1 (so_map (or alm)) – the window function of survey 1, if input_alm=True, expect wlm1

• binning_file (text file) – a binning file with three columns bin low, bin high, bin mean

• lmax (integer) – the maximum multipole to consider for the spectra computation

• type (string) – the type of binning, either bin Cl or bin Dl

• win2 (so_map (or alm)) – the window function of survey 2, if input_alm=True, expect wlm2

• bl1 (1d array) – the beam of survey 1, expected to start at l=0

• bl2 (1d array) – the beam of survey 2, expected to start at l=0

• niter (int) – specify the number of iteration in map2alm

• binned_mcm (boolean) – wether to bin or not the mcm

• save_file (boolean) – save the mcm and bbl to disk

• l_toep (int) –

• l_band (int) –

• l_exact (int) –

pspy.so_mcm.mcm_and_bbl_spin0and2(win1, binning_file, lmax, niter, type='Dl', win2=None, bl1=None, bl2=None, input_alm=False, pure=False, binned_mcm=True, save_file=None, l3_pad=2000, l_exact=None, l_toep=None, l_band=None, return_coupling_only=False)

Get the mode coupling matrix and the binning matrix for spin 0 and 2 fields

Parameters:

• win1 (python tuple of so_map or alms (if input_alm=True)) – a python tuple (win_spin0,win_spin2) with the window functions of survey 1, if input_alm=True, expect (wlm_spin0, wlm_spin2)

• binning_file (text file) – a binning file with three columns bin low, bin high, bin mean

• lmax (integer) – the maximum multipole to consider

• type (string) – the type of binning, either bin Cl or bin Dl

• win2 (python tuple of so_map or alms (if input_alm=True)) – a python tuple (win_spin0,win_spin2) with the window functions of survey 1, if input_alm=True, expect (wlm_spin0, wlm_spin2)

• bl1 (python tuple of 1d array) – a python tuple (beam_spin0,beam_spin2) with the beam of survey 1, expected to start at l=0

• bl2 (python tuple of 1d array) – a python tuple (beam_spin0,beam_spin2) with the beam of survey 2, expected to start at l=0

• niter (int) – specify the number of iteration in map2alm

• pureB (boolean) – do B mode purification

• binned_mcm (boolean) – wether to bin or not the mcm

• save_file (boolean) – save the mcm and bbl to disk

• l_toep (int) –

• l_band (int) –

• l_exact (int) –

• save_coupling (str) –

pspy.so_mcm.read_coupling(prefix, spin_pairs=None)

Read the inverse of the mode coupling matrix and the binning matrix :param prefix: the prefix for the name of the file :type prefix: string :param spin_pairs: needed for spin0 and 2 fields. :type spin_pairs: list of strings :param unbin: also read the unbin matrix :type unbin: boolean

pspy.so_mcm.save_coupling(prefix, mode_coupling_inv, Bbl, spin_pairs=None)

Save the inverse of the mode coupling matrix and the binning matrix in npy format

Parameters:

• prefix (string) – the prefix for the name of the file

• mode_coupling_inv (2d array (or dict of 2d array)) – the inverse of the mode coupling matrix, if spin pairs is not none, should be a dictionnary with entries - spin0xspin0, spin0xspin2, spin2xspin0, spin2xspin2

• Bbl (2d array (or dict of 2d array)) – the binning matrix,if spin pairs is not none, should be a dictionnary with entries - spin0xspin0, spin0xspin2, spin2xspin0, spin2xspin2 otherwise, it will be a single matrix.

• spin_pairs (list of strings) – needed for spin0 and 2 fields.