28 lines
630 B
Fortran
28 lines
630 B
Fortran
subroutine wav11(d2,npts,dd)
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! Convert i*2 data sampled at 12000 Hz to r*4 sampled at 11025 Hz.
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parameter (NZ11=60*11025,NZ12=60*12000)
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parameter (NFFT1=64*12000,NFFT2=64*11025)
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integer*2 d2(NZ12)
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real*4 dd(NZ11)
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real x(NFFT2)
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complex cx(0:NFFT1/2)
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equivalence (x,cx)
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save x,cx
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jz=min(NZ12,npts)
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x(1:jz)=d2(1:jz)
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x(jz+1:)=0.0
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call four2a(cx,nfft1,1,-1,0) !Forward FFT, r2c
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df=12000.0/NFFT1
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ia=5000.0/df
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cx(ia:)=0.0
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call four2a(cx,nfft2,1,1,-1) !Inverse FFT, c2r
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npts=jz*11025.0/12000.0
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fac=1.e-6
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dd(1:npts)=fac*x(1:npts)
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return
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end subroutine wav11
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