mirror of https://gitlab.com/QEF/q-e.git
38 lines
825 B
Fortran
38 lines
825 B
Fortran
!
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! Copyright (C) 2001 PWSCF group
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! This file is distributed under the terms of the
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! GNU General Public License. See the file `License'
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! in the root directory of the present distribution,
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! or http://www.gnu.org/copyleft/gpl.txt .
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!
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!-----------------------------------------------------------------------
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subroutine swap (n, x, x1)
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!-----------------------------------------------------------------------
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! swap array x with array x1
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!
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USE kinds
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implicit none
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!
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! I/O variables
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!
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integer :: n
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! input: dimension of the vector
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real(kind=DP) :: x (n), x1 (n)
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! I/O: the vectors
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!
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! local variables
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!
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integer :: i
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! counter on the elements
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real(kind=DP) :: xswap
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! work
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do i = 1, n
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xswap = x (i)
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x (i) = x1 (i)
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x1 (i) = xswap
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enddo
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return
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end subroutine swap
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