Home > matutils > interf > mosaic_map.m

mosaic_map

PURPOSE ^

mos=mosaic_map(ad,ads,p,beam,uvcut)

SYNOPSIS ^

function mos=mosaic_map(ad,ads,p,beam,uvcut)

DESCRIPTION ^

 mos=mosaic_map(ad,ads,p,beam,uvcut)

 Make mosaic map by linear addition of individual dirty maps
 Called linear mosaicing. e.g. eqn 9&10 in astro-ph/0205388
 or eqn 20-2 in SIIRA.

 ad is big grid
 ads is per point grid
 beam is stack of primary beams one per band
 uvcut is uvr cut range

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

0001 function mos=mosaic_map(ad,ads,p,beam,uvcut)
0002 % mos=mosaic_map(ad,ads,p,beam,uvcut)
0003 %
0004 % Make mosaic map by linear addition of individual dirty maps
0005 % Called linear mosaicing. e.g. eqn 9&10 in astro-ph/0205388
0006 % or eqn 20-2 in SIIRA.
0007 %
0008 % ad is big grid
0009 % ads is per point grid
0010 % beam is stack of primary beams one per band
0011 % uvcut is uvr cut range
0012 
0013 if(~exist('uvcut'))
0014   uvcut=[0,Inf];
0015 end
0016 
0017 % Take the mean beam to unfold with - in principle one could
0018 % make a dmap for each band separately and unfold band by band...
0019 beam=mean(beam,3);
0020 
0021 % Generate individual maps
0022 a=zeros(ad.N_pix); b=a;
0023 for i=1:length(p.px)
0024   i
0025   % Filter vis
0026   uvr=pyth(p.u{i},p.v{i});
0027   ind=uvr>uvcut(1)&uvr<uvcut(2);
0028   
0029   % Make dirty map
0030   tic
0031   [dmap,s]=difmap(ads,p.u{i}(ind),p.v{i}(ind),p.vis{i}(ind),p.var{i}(ind));
0032   toc
0033   
0034   % Shift dmap and beam to pointing center
0035   x=ads.x+p.px(i); y=ads.y+p.py(i);
0036   tic
0037   sdmap=interp2(x,y,dmap,ad.x,ad.y); sdmap(isnan(sdmap))=0;
0038   sbeam=interp2(x,y,beam,ad.x,ad.y); sbeam(isnan(sbeam))=0;
0039   toc
0040   
0041   % Acculmulate arrays to make mosaic map
0042   a=a+sbeam.^2./s;
0043   b=b+sbeam.*sdmap./s;
0044 end
0045 
0046 % Calculate noise and signal maps
0047 mos.noise=sqrt(1./a);
0048 mos.signal=b./a;
0049 
0050 % calc "significance image"
0051 mos.sigma=mos.signal./mos.noise;
0052 
0053 return

Generated on Sun 14-Jun-2015 17:12:45 by m2html © 2005