2005-03-05 01:46:02 +08:00
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!
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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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!-----------------------------------------------------------------------
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subroutine symram (phi, nsym, s, nat, irt)
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!-----------------------------------------------------------------------
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!
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! Symmetrizes the Raman tensor.
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! The tensor in input is a real tensor in crystal coordinates.
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! The first two indexes correspond to the electric fields; the third
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! to atomic displacements
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!
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#include "f_defs.h"
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use kinds, only : DP
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implicit none
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integer :: nsym, s (3, 3, 48), nat, irt (48, nat)
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! input: the number of symmetries
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! input: the rotation matrix
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! input: the number of atoms
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! input: correspondence between rotated atoms
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2005-08-28 22:09:42 +08:00
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real(DP) :: phi (3, 3, 3, nat)
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2005-03-05 01:46:02 +08:00
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! matrix to symmetrize
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integer :: isym, i, j, k, l, m, n, na, sna
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! counter on symmetries
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! counter on axis
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! counter on atoms
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! the rotated atom
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2005-08-28 22:09:42 +08:00
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real(DP) :: work (3, 3, 3, nat)
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2005-03-05 01:46:02 +08:00
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! auxiliary work space
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!
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if (nsym == 1) return
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!
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work(:,:,:,:) = 0.d0
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!
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do na = 1, nat
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do isym = 1, nsym
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sna = irt (isym, na)
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do i = 1, 3
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do j = 1, 3
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do k = 1, 3
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do l = 1, 3
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do m = 1, 3
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do n = 1, 3
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work (i, j, k, na) = work (i, j, k, na) + &
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s (i, l, isym) * &
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s (j, m, isym) * &
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s (k, n, isym) * phi (l, m, n, sna)
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enddo
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enddo
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enddo
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enddo
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enddo
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enddo
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enddo
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enddo
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!
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General cleanup of intrinsic functions:
conversion to real => DBLE
(including real part of a complex number)
conversion to complex => CMPLX
complex conjugate => CONJG
imaginary part => AIMAG
All functions are uppercase.
CMPLX is preprocessed by f_defs.h and performs an explicit cast:
#define CMPLX(a,b) cmplx(a,b,kind=DP)
This implies that 1) f_defs.h must be included whenever a CMPLX is present,
2) CMPLX should stay in a single line, 3) DP must be defined.
All occurrences of real, float, dreal, dfloat, dconjg, dimag, dcmplx
removed - please do not reintroduce any of them.
Tested only with ifc7 and g95 - beware unintended side effects
Maybe not the best solution (explicit casts everywhere would be better)
but it can be easily changed with a script if the need arises.
The following code might be used to test for possible trouble:
program test_intrinsic
implicit none
integer, parameter :: dp = selected_real_kind(14,200)
real (kind=dp) :: a = 0.123456789012345_dp
real (kind=dp) :: b = 0.987654321098765_dp
complex (kind=dp) :: c = ( 0.123456789012345_dp, 0.987654321098765_dp)
print *, ' A = ', a
print *, ' DBLE(A)= ', DBLE(a)
print *, ' C = ', c
print *, 'CONJG(C)= ', CONJG(c)
print *, 'DBLE(c),AIMAG(C) = ', DBLE(c), AIMAG(c)
print *, 'CMPLX(A,B,kind=dp)= ', CMPLX( a, b, kind=dp)
end program test_intrinsic
Note that CMPLX and REAL without a cast yield single precision numbers on
ifc7 and g95 !!!
git-svn-id: http://qeforge.qe-forge.org/svn/q-e/trunk/espresso@2133 c92efa57-630b-4861-b058-cf58834340f0
2005-08-27 01:44:42 +08:00
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phi(:,:,:,:) = work(:,:,:,:) / DBLE (nsym)
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2005-03-05 01:46:02 +08:00
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!
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return
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end subroutine symram
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