2 ***********************************************************
3 $SNARK_Header: S N A R K 1 4 - A PICTURE RECONSTRUCTION PROGRAM $
4 $HeadURL: svn://dig.cs.gc.cuny.edu/snark/trunk/src/snark/foru_bckwrd.cpp $
5 $LastChangedRevision: 85 $
6 $Date: 2014-07-02 16:07:08 -0400 (Wed, 02 Jul 2014) $
8 ***********************************************************
10 PURPOSE: PERFORM BACKTRANSFORM THEN CALL SUBROUTINE FTFILL TO
11 STORE THE VALUES IN THE ARRAY RECON
24 void foru_class::bckwrd(REAL* recon)
41 n3 = Fourie.nsize2 + 2;
44 // PERFORM BACKTRANSFORM
46 fact = (REAL) 1.0 / (GeoPar.pixsiz * GeoPar.pixsiz);
48 fft(Fourie.nfrpln, Fourie.nback, invdir, fact);
51 fprintf(output, "\ntime for backtransform : %10.3f seconds ", tback); // changed precision to three digits - swr 1/21/06
55 // CALL FTFILL TO PUT THE NUMBERS IN RECON
56 ftfill(recon, Fourie.nfrpln, Fourie.nsize2);
59 // ADJUST THE NUMBERS IN RECON SO THAT THE AVERAGE DENSITY IS AVEDEN
61 for (k = 0; k < GeoPar.area; k++)
66 ave = sum / GeoPar.area;
67 adj = GeoPar.aveden - ave;
68 for (k = 0; k < GeoPar.area; k++)