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AMSS-NCKU/AMSS_NCKU_source/enforce_algebra.f90
2026-01-13 15:01:15 +08:00

199 lines
5.9 KiB
Fortran

!-----------------------------------------------------------------------------
!
! remove the trace of Aij
! trace-free Aij and enforce the determinant of bssn metric to one
!-----------------------------------------------------------------------------
subroutine enforce_ag(ex, dxx, gxy, gxz, dyy, gyz, dzz, &
Axx, Axy, Axz, Ayy, Ayz, Azz)
implicit none
!~~~~~~> Input parameters:
integer, intent(in) :: ex(1:3)
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: dxx,dyy,dzz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: gxy,gxz,gyz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: Axx,Axy,Axz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: Ayy,Ayz,Azz
!~~~~~~~> Local variable:
real*8, dimension(ex(1),ex(2),ex(3)) :: trA,detg
real*8, dimension(ex(1),ex(2),ex(3)) :: gxx,gyy,gzz
real*8, dimension(ex(1),ex(2),ex(3)) :: gupxx,gupxy,gupxz,gupyy,gupyz,gupzz
real*8, parameter :: F1o3 = 1.D0 / 3.D0, ONE = 1.D0, TWO = 2.D0
!~~~~~~>
gxx = dxx + ONE
gyy = dyy + ONE
gzz = dzz + ONE
detg = gxx * gyy * gzz + gxy * gyz * gxz + gxz * gxy * gyz - &
gxz * gyy * gxz - gxy * gxy * gzz - gxx * gyz * gyz
gupxx = ( gyy * gzz - gyz * gyz ) / detg
gupxy = - ( gxy * gzz - gyz * gxz ) / detg
gupxz = ( gxy * gyz - gyy * gxz ) / detg
gupyy = ( gxx * gzz - gxz * gxz ) / detg
gupyz = - ( gxx * gyz - gxy * gxz ) / detg
gupzz = ( gxx * gyy - gxy * gxy ) / detg
trA = gupxx * Axx + gupyy * Ayy + gupzz * Azz &
+ TWO * (gupxy * Axy + gupxz * Axz + gupyz * Ayz)
Axx = Axx - F1o3 * gxx * trA
Axy = Axy - F1o3 * gxy * trA
Axz = Axz - F1o3 * gxz * trA
Ayy = Ayy - F1o3 * gyy * trA
Ayz = Ayz - F1o3 * gyz * trA
Azz = Azz - F1o3 * gzz * trA
detg = ONE / ( detg ** F1o3 )
gxx = gxx * detg
gxy = gxy * detg
gxz = gxz * detg
gyy = gyy * detg
gyz = gyz * detg
gzz = gzz * detg
dxx = gxx - ONE
dyy = gyy - ONE
dzz = gzz - ONE
return
end subroutine enforce_ag
#if 1
!----------------------------------------------------------------------------------
! swap the turn of a and g
!----------------------------------------------------------------------------------
subroutine enforce_ga(ex, dxx, gxy, gxz, dyy, gyz, dzz, &
Axx, Axy, Axz, Ayy, Ayz, Azz)
implicit none
!~~~~~~> Input parameters:
integer, intent(in) :: ex(1:3)
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: dxx,dyy,dzz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: gxy,gxz,gyz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: Axx,Axy,Axz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: Ayy,Ayz,Azz
!~~~~~~~> Local variable:
real*8, dimension(ex(1),ex(2),ex(3)) :: trA
real*8, dimension(ex(1),ex(2),ex(3)) :: gxx,gyy,gzz
real*8, dimension(ex(1),ex(2),ex(3)) :: gupxx,gupxy,gupxz,gupyy,gupyz,gupzz
real*8, parameter :: F1o3 = 1.D0 / 3.D0, ONE = 1.D0, TWO = 2.D0
!~~~~~~>
gxx = dxx + ONE
gyy = dyy + ONE
gzz = dzz + ONE
! for g
gupzz = gxx * gyy * gzz + gxy * gyz * gxz + gxz * gxy * gyz - &
gxz * gyy * gxz - gxy * gxy * gzz - gxx * gyz * gyz
gupzz = ONE / ( gupzz ** F1o3 )
gxx = gxx * gupzz
gxy = gxy * gupzz
gxz = gxz * gupzz
gyy = gyy * gupzz
gyz = gyz * gupzz
gzz = gzz * gupzz
dxx = gxx - ONE
dyy = gyy - ONE
dzz = gzz - ONE
! for A
gupxx = ( gyy * gzz - gyz * gyz )
gupxy = - ( gxy * gzz - gyz * gxz )
gupxz = ( gxy * gyz - gyy * gxz )
gupyy = ( gxx * gzz - gxz * gxz )
gupyz = - ( gxx * gyz - gxy * gxz )
gupzz = ( gxx * gyy - gxy * gxy )
trA = gupxx * Axx + gupyy * Ayy + gupzz * Azz &
+ TWO * (gupxy * Axy + gupxz * Axz + gupyz * Ayz)
Axx = Axx - F1o3 * gxx * trA
Axy = Axy - F1o3 * gxy * trA
Axz = Axz - F1o3 * gxz * trA
Ayy = Ayy - F1o3 * gyy * trA
Ayz = Ayz - F1o3 * gyz * trA
Azz = Azz - F1o3 * gzz * trA
return
end subroutine enforce_ga
#else
!----------------------------------------------------------------------------------
! duplicate bam
!----------------------------------------------------------------------------------
subroutine enforce_ga(ex, dxx, gxy, gxz, dyy, gyz, dzz, &
Axx, Axy, Axz, Ayy, Ayz, Azz)
implicit none
!~~~~~~> Input parameters:
integer, intent(in) :: ex(1:3)
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: dxx,dyy,dzz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: gxy,gxz,gyz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: Axx,Axy,Axz
real*8, dimension(ex(1),ex(2),ex(3)), intent(inout) :: Ayy,Ayz,Azz
!~~~~~~~> Local variable:
real*8, dimension(ex(1),ex(2),ex(3)) :: trA
real*8, dimension(ex(1),ex(2),ex(3)) :: gxx,gyy,gzz
real*8, dimension(ex(1),ex(2),ex(3)) :: aux,detginv
real*8, parameter :: oot = 1.D0 / 3.D0, ONE = 1.D0, TWO = 2.D0
!~~~~~~>
gxx = dxx + ONE
gyy = dyy + ONE
gzz = dzz + ONE
! for g
aux = (2.d0*gxy*gxz*gyz + gxx*gyy*gzz &
- gzz*gxy**2 - gyy*gxz**2 - gxx*gyz**2)**(-oot)
gxx = gxx * aux
gxy = gxy * aux
gxz = gxz * aux
gyy = gyy * aux
gyz = gyz * aux
gzz = gzz * aux
dxx = gxx - ONE
dyy = gyy - ONE
dzz = gzz - ONE
! for A
detginv = 1/(2.d0*gxy*gxz*gyz + gxx*gyy*gzz &
- gzz*gxy**2 - gyy*gxz**2 - gxx*gyz**2)
trA = detginv*(-2.d0*Ayz*gxx*gyz + Axx*gyy*gzz + &
gxx*(Azz*gyy + Ayy*gzz) + 2.d0*(gxz*(Ayz*gxy - Axz*gyy + &
Axy*gyz) + gxy*(Axz*gyz - Axy*gzz)) - Azz*gxy**2 - Ayy*gxz**2 - &
Axx*gyz**2)
aux = -(oot*trA)
Axx = Axx + aux * gxx
Axy = Axy + aux * gxy
Axz = Axz + aux * gxz
Ayy = Ayy + aux * gyy
Ayz = Ayz + aux * gyz
Azz = Azz + aux * gzz
return
end subroutine enforce_ga
#endif