1 files changed, 38 insertions, 0 deletions
diff --git a/src/matexp.F90 b/src/matexp.F90
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+++ b/src/matexp.F90
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+! $Header$
+
+#include "cctk.h"
+#include "cctk_Parameters.h"
+
+module matexp
+  use constants
+  implicit none
+  DECLARE_CCTK_PARAMETERS
+  private
+  
+  public calc_exp3
+  
+contains
+  
+  subroutine calc_exp3 (h3, g3)
+    CCTK_REAL, intent(in)  :: h3(3,3)
+    CCTK_REAL, intent(out) :: g3(3,3)
+    CCTK_REAL :: nfact
+    CCTK_REAL :: tmp(3,3)
+    integer   :: n
+    integer   :: i, j
+    
+    g3 = delta3
+    
+    nfact = 1
+    tmp = delta3
+    do n = 1, 18
+       nfact = nfact * n
+       tmp = matmul (h3, tmp)
+       
+       ! exp(x) = sum_n x^n / n!
+       g3 = g3 + tmp / nfact
+    end do
+    
+  end subroutine calc_exp3
+  
+end module matexp