From b989b81d16cab40bf958bc10f03020ead2339a18 Mon Sep 17 00:00:00 2001
From: Will Bainbridge <http://cfd.direct>
Date: Thu, 31 May 2018 14:23:15 +0100
Subject: [PATCH] VectorSpace, Vector: Added findMin, findMax and perpendicular
 functions

The functions findMin and findMax return the index of the minimum or
maximum component, consistently with the functions in ListOps.H. The
perpendicular function returns an arbitrary vector perpendicular to the
supplied vector, with the same magnitude.
---
 src/OpenFOAM/primitives/Vector/VectorI.H      | 13 +++++++++-
 .../primitives/VectorSpace/VectorSpaceI.H     | 24 +++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/src/OpenFOAM/primitives/Vector/VectorI.H b/src/OpenFOAM/primitives/Vector/VectorI.H
index 518a398dc..7cde6e3b0 100644
--- a/src/OpenFOAM/primitives/Vector/VectorI.H
+++ b/src/OpenFOAM/primitives/Vector/VectorI.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2018 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -160,6 +160,17 @@ inline Vector<Cmpt> operator^(const Vector<Cmpt>& v1, const Vector<Cmpt>& v2)
 }
 
 
+// * * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * //
+
+template<class Cmpt>
+inline Vector<Cmpt> perpendicular(const Vector<Cmpt>& v)
+{
+    Vector<Cmpt> u(Zero);
+    u[findMin(cmptMag(v))] = 1;
+    return u ^ v;
+}
+
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 } // End namespace Foam
diff --git a/src/OpenFOAM/primitives/VectorSpace/VectorSpaceI.H b/src/OpenFOAM/primitives/VectorSpace/VectorSpaceI.H
index afd654cd3..fb30cb0ef 100644
--- a/src/OpenFOAM/primitives/VectorSpace/VectorSpaceI.H
+++ b/src/OpenFOAM/primitives/VectorSpace/VectorSpaceI.H
@@ -620,6 +620,30 @@ inline typename innerProduct<Form1, Form2>::type dot
 }
 
 
+template<class Form, class Cmpt, direction Ncmpts>
+inline direction findMax(const VectorSpace<Form, Cmpt, Ncmpts>& vs)
+{
+    direction index = 0;
+    for (direction i=1; i<Ncmpts; ++i)
+    {
+        index = vs[index] > vs[i] ? index : i;
+    }
+    return index;
+}
+
+
+template<class Form, class Cmpt, direction Ncmpts>
+inline direction findMin(const VectorSpace<Form, Cmpt, Ncmpts>& vs)
+{
+    direction index = 0;
+    for (direction i=1; i<Ncmpts; ++i)
+    {
+        index = vs[index] < vs[i] ? index : i;
+    }
+    return index;
+}
+
+
 // * * * * * * * * * * * * * * * Global Operators  * * * * * * * * * * * * * //
 
 template<class Form, class Cmpt, direction Ncmpts>