Add some commented-out code to calculate the Ricci tensor in an

alternate way.


git-svn-id: http://svn.einsteintoolkit.org/cactus/EinsteinUtils/TGRtensor/trunk@37 b716e942-a2de-43ad-8f52-f3dfe468e4e7

1 files changed, 27 insertions, 0 deletions

diff --git a/src/ricci4.F90 b/src/ricci4.F90
index 162817a..241c86a 100644
--- a/src/ricci4.F90
+++ b/src/ricci4.F90
@@ -62,6 +62,7 @@ contains
     CCTK_REAL :: nrm, cnt
 #endif
     integer :: i,j,k,l
+#if 1
     ! R_ij =   Gamma^k_ij,k - Gamma^k_ik,j
     !        + Gamma^k_lk Gamma^l_ij - Gamma^k_lj Gamma^l_ki
     do i=1,4
@@ -76,6 +77,32 @@ contains
           end do
        end do
     end do
+#else
+    CCTK_REAL :: rmu(4,4,4,4)
+    integer   :: m
+    do i=1,4
+       do j=1,4
+          do k=1,4
+             do l=1,4
+                rmu(i,j,k,l) = dgamma(i,j,l,k) - dgamma(i,j,k,l)
+                do m=1,4
+                   rmu(i,j,k,l) = rmu(i,j,k,l) &
+                        + gamma(m,j,l) * gamma(i,m,k) &
+                        - gamma(m,j,k) * gamma(i,m,l)
+                end do
+             end do
+          end do
+       end do
+    end do
+    do i=1,4
+       do j=1,4
+          ri(i,j) = 0
+          do k=1,4
+             ri(i,j) = ri(i,j) + rmu(k,i,k,j)
+          end do
+       end do
+    end do
+#endif
 #ifdef DEBUG
     ! check symmetries
     nrm = 0