22 lines
530 B
Plaintext
22 lines
530 B
Plaintext
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subroutine ana932(dat,npts0,cdat,npts)
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real dat(npts0)
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complex cdat(262145)
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n=log(float(npts0))/log(2.0)
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nfft1=2**(n+1)
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nfft2=9*nfft1/32
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df932=11025.0/nfft1
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fac=2.0/nfft1
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do i=1,npts0/2
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cdat(i)=fac*cmplx(dat(2*i-1),dat(2*i))
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enddo
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cdat(npts0/2+1:nfft1/2)=0.
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call four2a(cdat,nfft1,1,-1,0) !Forward r2c FFT
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call four2a(cdat,nfft2,1,1,1) !Inverse c2c FFT
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npts=npts0*9.0/32.0 !Downsampled data length
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npts2=npts
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return
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end subroutine ana932
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