quantum-espresso/Modules/sort.f90

358 lines
10 KiB
Fortran

!
! Copyright (C) 2001 PWSCF group
! This file is distributed under the terms of the
! GNU General Public License. See the file `License'
! in the root directory of the present distribution,
! or http://www.gnu.org/copyleft/gpl.txt .
!
!---------------------------------------------------------------------
subroutine hpsort_eps (n, ra, ind, eps)
!---------------------------------------------------------------------
! sort an array ra(1:n) into ascending order using heapsort algorithm,
! and considering two elements being equal if their values differ
! for less than "eps".
! n is input, ra is replaced on output by its sorted rearrangement.
! create an index table (ind) by making an exchange in the index array
! whenever an exchange is made on the sorted data array (ra).
! in case of equal values in the data array (ra) the values in the
! index array (ind) are used to order the entries.
! if on input ind(1) = 0 then indices are initialized in the routine,
! if on input ind(1) != 0 then indices are assumed to have been
! initialized before entering the routine and these
! indices are carried around during the sorting process
!
! no work space needed !
! free us from machine-dependent sorting-routines !
!
! adapted from Numerical Recipes pg. 329 (new edition)
!
use kinds, only : DP
implicit none
!-input/output variables
integer, intent(in) :: n
integer, intent(inout) :: ind (*)
real(DP), intent(inout) :: ra (*)
real(DP), intent(in) :: eps
!-local variables
integer :: i, ir, j, l, iind
real(DP) :: rra
! initialize index array
if (ind (1) .eq.0) then
do i = 1, n
ind (i) = i
enddo
endif
! nothing to order
if (n.lt.2) return
! initialize indices for hiring and retirement-promotion phase
l = n / 2 + 1
ir = n
sorting: do
! still in hiring phase
if ( l .gt. 1 ) then
l = l - 1
rra = ra (l)
iind = ind (l)
! in retirement-promotion phase.
else
! clear a space at the end of the array
rra = ra (ir)
!
iind = ind (ir)
! retire the top of the heap into it
ra (ir) = ra (1)
!
ind (ir) = ind (1)
! decrease the size of the corporation
ir = ir - 1
! done with the last promotion
if ( ir .eq. 1 ) then
! the least competent worker at all !
ra (1) = rra
!
ind (1) = iind
exit sorting
endif
endif
! wheter in hiring or promotion phase, we
i = l
! set up to place rra in its proper level
j = l + l
!
do while ( j .le. ir )
if ( j .lt. ir ) then
! compare to better underling
if ( abs(ra(j)-ra(j+1)).ge.eps ) then
if (ra(j).lt.ra(j+1)) j = j + 1
else
! this means ra(j) == ra(j+1) within tolerance
if (ind (j) .lt.ind (j + 1) ) j = j + 1
endif
endif
! demote rra
if ( abs(rra - ra(j)).ge.eps ) then
if (rra.lt.ra(j)) then
ra (i) = ra (j)
ind (i) = ind (j)
i = j
j = j + j
else
! set j to terminate do-while loop
j = ir + 1
end if
else
!this means rra == ra(j) within tolerance
! demote rra
if (iind.lt.ind (j) ) then
ra (i) = ra (j)
ind (i) = ind (j)
i = j
j = j + j
else
! set j to terminate do-while loop
j = ir + 1
endif
end if
enddo
ra (i) = rra
ind (i) = iind
end do sorting
!
end subroutine hpsort_eps
!
! Copyright (C) 2001 PWSCF group
! This file is distributed under the terms of the
! GNU General Public License. See the file `License'
! in the root directory of the present distribution,
! or http://www.gnu.org/copyleft/gpl.txt .
!
!---------------------------------------------------------------------
subroutine hpsort (n, ra, ind)
!---------------------------------------------------------------------
! sort an array ra(1:n) into ascending order using heapsort algorithm.
! n is input, ra is replaced on output by its sorted rearrangement.
! create an index table (ind) by making an exchange in the index array
! whenever an exchange is made on the sorted data array (ra).
! in case of equal values in the data array (ra) the values in the
! index array (ind) are used to order the entries.
! if on input ind(1) = 0 then indices are initialized in the routine,
! if on input ind(1) != 0 then indices are assumed to have been
! initialized before entering the routine and these
! indices are carried around during the sorting process
!
! no work space needed !
! free us from machine-dependent sorting-routines !
!
! adapted from Numerical Recipes pg. 329 (new edition)
!
use kinds, only : DP
implicit none
!-input/output variables
integer :: n
integer :: ind (*)
real(DP) :: ra (*)
!-local variables
integer :: i, ir, j, l, iind
real(DP) :: rra
! initialize index array
if (ind (1) .eq.0) then
do i = 1, n
ind (i) = i
enddo
endif
! nothing to order
if (n.lt.2) return
! initialize indices for hiring and retirement-promotion phase
l = n / 2 + 1
ir = n
10 continue
! still in hiring phase
if (l.gt.1) then
l = l - 1
rra = ra (l)
iind = ind (l)
! in retirement-promotion phase.
else
! clear a space at the end of the array
rra = ra (ir)
!
iind = ind (ir)
! retire the top of the heap into it
ra (ir) = ra (1)
!
ind (ir) = ind (1)
! decrease the size of the corporation
ir = ir - 1
! done with the last promotion
if (ir.eq.1) then
! the least competent worker at all !
ra (1) = rra
!
ind (1) = iind
return
endif
endif
! wheter in hiring or promotion phase, we
i = l
! set up to place rra in its proper level
j = l + l
!
do while (j.le.ir)
if (j.lt.ir) then
! compare to better underling
if (ra (j) .lt.ra (j + 1) ) then
j = j + 1
elseif (ra (j) .eq.ra (j + 1) ) then
if (ind (j) .lt.ind (j + 1) ) j = j + 1
endif
endif
! demote rra
if (rra.lt.ra (j) ) then
ra (i) = ra (j)
ind (i) = ind (j)
i = j
j = j + j
elseif (rra.eq.ra (j) ) then
! demote rra
if (iind.lt.ind (j) ) then
ra (i) = ra (j)
ind (i) = ind (j)
i = j
j = j + j
else
! set j to terminate do-while loop
j = ir + 1
endif
! this is the right place for rra
else
! set j to terminate do-while loop
j = ir + 1
endif
enddo
ra (i) = rra
ind (i) = iind
goto 10
!
end subroutine hpsort
!
! Copyright (C) 2001 PWSCF group
! This file is distributed under the terms of the
! GNU General Public License. See the file `License'
! in the root directory of the present distribution,
! or http://www.gnu.org/copyleft/gpl.txt .
!
!---------------------------------------------------------------------
subroutine ihpsort (n, ia, ind)
!---------------------------------------------------------------------
! sort an integer array ia(1:n) into ascending order using heapsort algorithm.
! n is input, ia is replaced on output by its sorted rearrangement.
! create an index table (ind) by making an exchange in the index array
! whenever an exchange is made on the sorted data array (ia).
! in case of equal values in the data array (ia) the values in the
! index array (ind) are used to order the entries.
! if on input ind(1) = 0 then indices are initialized in the routine,
! if on input ind(1) != 0 then indices are assumed to have been
! initialized before entering the routine and these
! indices are carried around during the sorting process
!
! no work space needed !
! free us from machine-dependent sorting-routines !
!
! adapted from Numerical Recipes pg. 329 (new edition)
!
implicit none
!-input/output variables
integer :: n
integer :: ind (*)
integer :: ia (*)
!-local variables
integer :: i, ir, j, l, iind
integer :: iia
! initialize index array
if (ind (1) .eq.0) then
do i = 1, n
ind (i) = i
enddo
endif
! nothing to order
if (n.lt.2) return
! initialize indices for hiring and retirement-promotion phase
l = n / 2 + 1
ir = n
10 continue
! still in hiring phase
if (l.gt.1) then
l = l - 1
iia = ia (l)
iind = ind (l)
! in retirement-promotion phase.
else
! clear a space at the end of the array
iia = ia (ir)
!
iind = ind (ir)
! retire the top of the heap into it
ia (ir) = ia (1)
!
ind (ir) = ind (1)
! decrease the size of the corporation
ir = ir - 1
! done with the last promotion
if (ir.eq.1) then
! the least competent worker at all !
ia (1) = iia
!
ind (1) = iind
return
endif
endif
! wheter in hiring or promotion phase, we
i = l
! set up to place iia in its proper level
j = l + l
!
do while (j.le.ir)
if (j.lt.ir) then
! compare to better underling
if (ia (j) .lt.ia (j + 1) ) then
j = j + 1
elseif (ia (j) .eq.ia (j + 1) ) then
if (ind (j) .lt.ind (j + 1) ) j = j + 1
endif
endif
! demote iia
if (iia.lt.ia (j) ) then
ia (i) = ia (j)
ind (i) = ind (j)
i = j
j = j + j
elseif (iia.eq.ia (j) ) then
! demote iia
if (iind.lt.ind (j) ) then
ia (i) = ia (j)
ind (i) = ind (j)
i = j
j = j + j
else
! set j to terminate do-while loop
j = ir + 1
endif
! this is the right place for iia
else
! set j to terminate do-while loop
j = ir + 1
endif
enddo
ia (i) = iia
ind (i) = iind
goto 10
!
end subroutine ihpsort