From d2f3c9e3ecdca19a6999fd1fb1291d4bcf8a2198 Mon Sep 17 00:00:00 2001
From: Alex Selimov <alsel@tuta.io>
Date: Wed, 4 Mar 2020 21:06:12 -0500
Subject: [PATCH] Add check for orientation to make sure it's right handed and
 orthogonal

---
 src/opt_orient.f90 | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/opt_orient.f90 b/src/opt_orient.f90
index 21d9d3f..c1bef1e 100644
--- a/src/opt_orient.f90
+++ b/src/opt_orient.f90
@@ -20,6 +20,7 @@ module opt_orient
         integer, intent(inout) :: arg_pos
 
         integer :: i, ibasis, inod
+        logical :: isortho, isrighthanded
         real(kind=dp) :: inv_sub_box_ori(3,3,sub_box_num)
 
         !First parse the orient command
@@ -70,6 +71,7 @@ module opt_orient
         integer, intent(inout) :: arg_pos
 
         integer :: i, arg_len
+        logical :: isortho, isrighthanded
         character(len=8) :: ori_string
 
         !Pull out the new user orientation
@@ -82,6 +84,15 @@ module opt_orient
 
         !Normalize the orientation matrix
         new_orient = matrix_normal(new_orient,3)
+
+        !Check right hand rule and orthogonality
+        call check_right_ortho(new_orient, isortho, isrighthanded)
+        if (.not.isortho) then 
+            stop "Directions in orient are not orthogonal"
+        else if (.not.isrighthanded) then 
+            stop "Directions in orient are not righthanded"
+        end if
+
         arg_pos = arg_pos + 1
 
     end subroutine parse_orient