From 6207432f7ae0e2270303248c8b1d54c7d1b59a01 Mon Sep 17 00:00:00 2001
From: Martin Diehl <mail@martin-diehl.net>
Date: Mon, 28 Dec 2020 21:34:14 +0100
Subject: [PATCH] modern Fortran

---
 src/math.f90 | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/math.f90 b/src/math.f90
index 8005b5406..6b89a9923 100644
--- a/src/math.f90
+++ b/src/math.f90
@@ -279,9 +279,12 @@ real(pReal) pure function math_LeviCivita(i,j,k)
 
   integer, intent(in) :: i,j,k
 
-  if     (all([i,j,k] == [1,2,3]) .or. all([i,j,k] == [2,3,1]) .or. all([i,j,k] == [3,1,2])) then
+  integer :: o
+
+
+  if     (any([(all(cshift([i,j,k],o) == [1,2,3]),o=0,2)])) then
     math_LeviCivita = +1.0_pReal
-  elseif (all([i,j,k] == [3,2,1]) .or. all([i,j,k] == [2,1,3]) .or. all([i,j,k] == [1,3,2])) then
+  elseif (any([(all(cshift([i,j,k],o) == [3,2,1]),o=0,2)])) then
     math_LeviCivita = -1.0_pReal
   else
     math_LeviCivita =  0.0_pReal