Inpaint module

inpaint.calccov(sim_mat, noofsims, npixels)

Computer pixel-pixel covarinace based on simulations.

Parameters:

sim_mat (array) – nd array multiple sim maps used for covariance.
noofsims (int) – number of simulations.
npixels (int) – Map dimension (number of pixels).

Returns:

cov – covarinace array. Same as np.cov(sim_mat).

Return type:

array

inpaint.get_covariance(ra_grid, dec_grid, mapparams, el, cl_dic, bl, nl_dic, noofsims, mask_radius_inner, mask_radius_outer, low_pass_cutoff=1, maxel_for_grad_filter=None)

Compute the covariance between regions R1 and R2 required for inpainting.

\[\hat{T}_{1} = \tilde{T}_{1} + {\bf \hat{C}}_{12} {\bf \hat{C}}_{22}^{-1} (T_{2} - \tilde{T}_{2})\]

Parameters:

ra_grid (array) – ra_grid in degrees or arcmins for the flatsky map.
dec_grid (array) – dec_grid in degress or arcmins for the flatsky map.
mapparams (list) – [nx, ny, dx, dy] where ny, nx = flatskymap.shape; and dy, dx are the pixel resolution in arcminutes. for example: [100, 100, 0.5, 0.5] is a 50’ x 50’ flatskymap that has dimensions 100 x 100 with dx = dy = 0.5 arcminutes.
el (array) – Multipoles over which the power spectrum is defined.
cl_dic (dict) – Signal power spectra dictionary. Keys are “TT” for T-only inpainting; “TT”, “EE”, “TE” for T/Q/U inpainting.
bl (array) – 1d beam window function. Default is None. Used for smoothing the maps.
nl_dic (dict) – Noise power spectra dictionary. Keys are “TT” for T-only inpainting; “TT”, “EE”, “TE” for T/Q/U inpainting.
noofsims (int) – number of simulations used for covariance calculation.
mask_radius_inner (float) – Inner radius of region R1 to inpaint in arcmins.
mask_radius_outer (float) – Outer radius of region R2 to inpaint in arcmins.
low_pass_cutoff (bool) – Low pass filter the maps before inpainting. Default is True.
maxel_for_grad_filter (int) – lmax for the LPF above. Default is None in which it will be calculated based on the radius of the inner region.

Returns:

sigma_dic – Covariance dictionary containing the covariance between R12, R22, and R22_inv. See the equation above.

Return type:

dict (Optional)

See also

inpainting

inpaint.get_mask_indices(ra_grid, dec_grid, mask_radius_inner, mask_radius_outer, square=0, in_arcmins=1)

Get the pixel indices in regions R1 and R2 for inpainting.

Parameters:

ra_grid (array) – ra_grid in degrees or arcmins for the flatsky map.
dec_grid (array) – dec_grid in degress or arcmins for the flatsky map.
mask_radius_inner (float) – Inner radius of region R1 to inpaint in arcmins.
mask_radius_outer (float) – Outer radius of region R2 to inpaint in arcmins.
low_pass_cutoff (bool) – Low pass filter the maps before inpainting. Default is True.
square (bool) – if True, returns a square. else, returns a cirucalr region. Default is Circle.
in_arcmins (bool) – Supplied grid are in arcmins. default is True. If False, degrees is assumed and will be converted to arcmins.

Returns:

inds_inner (array) – pixel indices of the inner region R1.
inds_outer (array) – pixel indices of the outer region R2.

inpaint.inpainting(map_dic_to_inpaint, ra_grid, dec_grid, mapparams, el, cl_dic, bl, nl_dic, noofsims, mask_radius_inner, mask_radius_outer, low_pass_cutoff=1, maxel_for_grad_filter=None, intrp_r1_before_lpf=0, mask_inner=0, sigma_dic=None, use_original=False, use_cons_gau_sims=True)

Perform inpainting. Can perform joint inpainting of T/Q/U maps using the cross-spectra between them. ###mask_inner = 1: The inner region is masked before the LPF. Might be useful in the presence of bright SZ signal at the centre.

\[\hat{T}_{1} = \tilde{T}_{1} + {\bf \hat{C}}_{12} {\bf \hat{C}}_{22}^{-1} (T_{2} - \tilde{T}_{2})\]

Parameters:

map_dic_to_inpaint (dict) – flatsky map dict to inpaint. Keys must be [“T”, “Q”, “U”].
ra_grid (array) – ra_grid in degrees or arcmins for the flatsky map.
dec_grid (array) – dec_grid in degress or arcmins for the flatsky map.
mapparams (list) – [nx, ny, dx, dy] where ny, nx = flatskymap.shape; and dy, dx are the pixel resolution in arcminutes. for example: [100, 100, 0.5, 0.5] is a 50’ x 50’ flatskymap that has dimensions 100 x 100 with dx = dy = 0.5 arcminutes.
el (array) – Multipoles over which the power spectrum is defined.
cl_dic (dict) – Signal power spectra dictionary. Keys are “TT” for T-only inpainting; “TT”, “EE”, “TE” for T/Q/U inpainting.
bl (array) – 1d beam window function. Default is None. Used for smoothing the maps.
nl_dic (dict) – Noise power spectra dictionary. Keys are “TT” for T-only inpainting; “TT”, “EE”, “TE” for T/Q/U inpainting.
noofsims (int) – number of simulations used for covariance calculation.
mask_radius_inner (float) – Inner radius of region R1 to inpaint in arcmins.
mask_radius_outer (float) – Outer radius of region R2 to inpaint in arcmins.
low_pass_cutoff (bool) – Low pass filter the maps before inpainting. Default is True.
maxel_for_grad_filter (int) – lmax for the LPF above. Default is None in which it will be calculated based on the radius of the inner region.
intrp_r1_before_lpf (bool) – Interpolate R1 before inpainting. Default is False.
mask_inner (bool) – Mask inner region before inpainting. Default is False.
sigma_dic (dict (Optional)) – Covariance dictionary containing the covariance between R12, R22, and R22_inv. See the equation above. If None, this will be calculated on the fly.
use_original (bool) – Do not inpaint. Return the same map. Default is False.
use_cons_gau_sims (bool) – Use constrained Gaussian realisations or not. If False, fields with tilde will be set to zero and there will be no randomness. (i.e:) Just interpolate R1 based on R2 and the covariance. default is True.

Returns:

cmb_inpainted_map (array) – inpainted CMB region. All pixels other than R1 will be zero in this map.
inpainted_map (array) – inpainted map.
map_to_inpaint (array) – original map used for inpainting.