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git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@2643 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
35 lines
803 B
Fortran
35 lines
803 B
Fortran
subroutine peakdt9(c0,npts8,nsps8,istart,foffset,idtpk)
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complex c0(0:npts8-1)
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complex zsum
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integer ii(16) !Locations of sync symbols
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data ii/1,6,11,16,21,26,31,39,45,51,57,63,69,75,81,85/
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twopi=8.0*atan(1.0)
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smax=0.
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f0=foffset
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dphi=twopi*f0/1500.0
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do idt=-5,5
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i0=istart + 0.0625*nsps8*idt
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sum=0.
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do j=1,16
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i1=(ii(j)-1)*nsps8 + i0
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phi=0.
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zsum=0.
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do i=i1,i1+nsps8-1
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if(i.lt.0 .or. i.gt.npts8-1) cycle
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phi=phi + dphi
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zsum=zsum + c0(i) * cmplx(cos(phi),-sin(phi))
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enddo
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sum=sum + real(zsum)**2 + aimag(zsum)**2
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enddo
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if(sum.gt.smax) then
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idtpk=idt
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smax=sum
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endif
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enddo
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return
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end subroutine peakdt9
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