44 lines
905 B
Fortran
44 lines
905 B
Fortran
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SUBROUTINE hunt(xx,n,x,jlo)
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INTEGER jlo,n
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REAL*8 x,xx(n)
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INTEGER inc,jhi,jm
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LOGICAL ascnd
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ascnd=xx(n).gt.xx(1)
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if(jlo.le.0.or.jlo.gt.n)then
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jlo=0
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jhi=n+1
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goto 3
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endif
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inc=1
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if(x.ge.xx(jlo).eqv.ascnd)then
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1 jhi=jlo+inc
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if(jhi.gt.n)then
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jhi=n+1
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else if(x.ge.xx(jhi).eqv.ascnd)then
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jlo=jhi
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inc=inc+inc
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goto 1
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endif
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else
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jhi=jlo
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2 jlo=jhi-inc
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if(jlo.lt.1)then
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jlo=0
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else if(x.lt.xx(jlo).eqv.ascnd)then
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jhi=jlo
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inc=inc+inc
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goto 2
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endif
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endif
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3 if(jhi-jlo.eq.1)return
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jm=(jhi+jlo)/2
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if(x.gt.xx(jm).eqv.ascnd)then
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jlo=jm
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else
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jhi=jm
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endif
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goto 3
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END
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C (C) Copr. 1986-92 Numerical Recipes Software $23#1yR.3Z9.
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