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										 |  |  | subroutine afc65b(cx,npts,fsample,nflip,mode65,a,ccfbest,dtbest) | 
					
						
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										 |  |  | 
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							|  |  |  | ! Find delta f, f1, f2 ==> a(1:3) | 
					
						
							|  |  |  | 
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							|  |  |  |   complex cx(npts) | 
					
						
							|  |  |  |   real a(5),deltaa(5) | 
					
						
							|  |  |  | 
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										 |  |  |   a=0. | 
					
						
							|  |  |  |   i2=8*mode65 | 
					
						
							|  |  |  |   i1=-i2 | 
					
						
							|  |  |  |   j2=8*mode65 | 
					
						
							|  |  |  |   j1=-j2 | 
					
						
							|  |  |  |   ccfmax=0. | 
					
						
							|  |  |  |   istep=2*mode65 | 
					
						
							|  |  |  |   do iter=1,2 | 
					
						
							|  |  |  |      do i=i1,i2,istep | 
					
						
							|  |  |  |         a(1)=i | 
					
						
							|  |  |  |         do j=j1,j2,istep | 
					
						
							|  |  |  |            a(2)=j | 
					
						
							|  |  |  |            chisq=fchisq65(cx,npts,fsample,nflip,a,ccf,dtmax) | 
					
						
							|  |  |  |            if(ccf.gt.ccfmax) then | 
					
						
							|  |  |  |               a1=a(1) | 
					
						
							|  |  |  |               a2=a(2) | 
					
						
							|  |  |  |               ccfmax=ccf | 
					
						
							|  |  |  |            endif | 
					
						
							|  |  |  | !           write(81,3081) istep,i1,i2,j1,j2,i,j,ccf,ccfmax,dtmax,a1,a2 | 
					
						
							|  |  |  | !3081       format(7i4,5f8.2) | 
					
						
							|  |  |  |         enddo | 
					
						
							|  |  |  |      enddo | 
					
						
							|  |  |  |      i1=a1-istep | 
					
						
							|  |  |  |      i2=a1+istep | 
					
						
							|  |  |  |      j1=a2-istep | 
					
						
							|  |  |  |      j2=a2+istep | 
					
						
							|  |  |  |      istep=1 | 
					
						
							|  |  |  |   enddo | 
					
						
							|  |  |  |    | 
					
						
							|  |  |  | !  a(1)=0. | 
					
						
							|  |  |  | !  a(2)=0. | 
					
						
							|  |  |  |   a(1)=a1 | 
					
						
							|  |  |  |   a(2)=a2 | 
					
						
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										 |  |  |   a(3)=0. | 
					
						
							|  |  |  |   a(4)=0. | 
					
						
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										 |  |  |   deltaa(1)=2.0*mode65 | 
					
						
							|  |  |  |   deltaa(2)=2.0*mode65 | 
					
						
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										 |  |  |   deltaa(3)=1.0 | 
					
						
							|  |  |  |   nterms=2                                  !Maybe 2 is enough? | 
					
						
							|  |  |  | 
 | 
					
						
							|  |  |  | !  Start the iteration | 
					
						
							|  |  |  |   chisqr=0. | 
					
						
							|  |  |  |   chisqr0=1.e6 | 
					
						
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										 |  |  |   do iter=1,100                              !How many iters is enough? | 
					
						
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										 |  |  |      do j=1,nterms | 
					
						
							|  |  |  |         chisq1=fchisq65(cx,npts,fsample,nflip,a,ccfmax,dtmax) | 
					
						
							|  |  |  |         fn=0. | 
					
						
							|  |  |  |         delta=deltaa(j) | 
					
						
							|  |  |  | 10      a(j)=a(j)+delta | 
					
						
							|  |  |  |         chisq2=fchisq65(cx,npts,fsample,nflip,a,ccfmax,dtmax) | 
					
						
							|  |  |  |         if(chisq2.eq.chisq1) go to 10 | 
					
						
							|  |  |  |         if(chisq2.gt.chisq1) then | 
					
						
							|  |  |  |            delta=-delta                      !Reverse direction | 
					
						
							|  |  |  |            a(j)=a(j)+delta | 
					
						
							|  |  |  |            tmp=chisq1 | 
					
						
							|  |  |  |            chisq1=chisq2 | 
					
						
							|  |  |  |            chisq2=tmp | 
					
						
							|  |  |  |         endif | 
					
						
							|  |  |  | 20      fn=fn+1.0 | 
					
						
							|  |  |  |         a(j)=a(j)+delta | 
					
						
							|  |  |  |         chisq3=fchisq65(cx,npts,fsample,nflip,a,ccfmax,dtmax) | 
					
						
							|  |  |  |         if(chisq3.lt.chisq2) then | 
					
						
							|  |  |  |            chisq1=chisq2 | 
					
						
							|  |  |  |            chisq2=chisq3 | 
					
						
							|  |  |  |            go to 20 | 
					
						
							|  |  |  |         endif | 
					
						
							|  |  |  | 
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							|  |  |  | ! Find minimum of parabola defined by last three points | 
					
						
							|  |  |  |         delta=delta*(1./(1.+(chisq1-chisq2)/(chisq3-chisq2))+0.5) | 
					
						
							|  |  |  |         a(j)=a(j)-delta | 
					
						
							|  |  |  |         deltaa(j)=deltaa(j)*fn/3. | 
					
						
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										 |  |  | !        write(*,4000) iter,j,a(1:2),-chisq2 | 
					
						
							|  |  |  | !4000    format(2i2,4f9.4) | 
					
						
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										 |  |  |      enddo | 
					
						
							|  |  |  |      chisqr=fchisq65(cx,npts,fsample,nflip,a,ccfmax,dtmax) | 
					
						
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										 |  |  |      fdiff=chisqr/chisqr0-1.0 | 
					
						
							|  |  |  | !     write(*,4000) 0,0,a(1:2),-chisqr,fdiff | 
					
						
							|  |  |  |      if(abs(fdiff).lt.0.0001) exit | 
					
						
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										 |  |  |      chisqr0=chisqr | 
					
						
							|  |  |  |   enddo | 
					
						
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										 |  |  |   ccfbest=ccfmax * (1378.125/fsample)**2 | 
					
						
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										 |  |  |   dtbest=dtmax | 
					
						
							|  |  |  | 
 | 
					
						
							|  |  |  |   return | 
					
						
							|  |  |  | end subroutine afc65b |