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27 lines
594 B
Fortran
27 lines
594 B
Fortran
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subroutine forwardstep(vec,n)
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implicit none
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integer n
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real vec(n)
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integer half, k, j
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half=n/2!changed to more than one
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do k=1,half
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vec(k)=vec(k)+sqrt(3.0)*vec(half+k)
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end do
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vec(half+1)=vec(half+1)-sqrt(3.0)/4.0*vec(1)- &
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(sqrt(3.0)-2)/4.0*vec(half)
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do k=1,half-1
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vec(half+k+1)=vec(half+k+1)-sqrt(3.0)/4.0*vec(k+1)- &
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(sqrt(3.0)-2)/4.0*vec(k)
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end do
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do k=1,half-1
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vec(k)=vec(k)-vec(half+k+1)
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end do
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vec(half)=vec(half)-vec(half+1)
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do k=1,half
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vec(k)=(sqrt(3.0)-1)/sqrt(2.0)*vec(k)
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vec(half+k)=(sqrt(3.0)+1)/sqrt(2.0)*vec(half+k)
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end do
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end subroutine
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