25 lines
496 B
Fortran
25 lines
496 B
Fortran
SUBROUTINE wt1(a,n,isign,wtstep)
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INTEGER isign,n
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REAL a(n)
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EXTERNAL wtstep
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CU USES wtstep
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INTEGER nn
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if (n.lt.4) return
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if (isign.ge.0) then
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nn=n
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1 if (nn.ge.4) then
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call wtstep(a,nn,isign)
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nn=nn/2
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goto 1
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endif
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else
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nn=4
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2 if (nn.le.n) then
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call wtstep(a,nn,isign)
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nn=nn*2
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goto 2
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endif
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endif
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return
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END
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