From db9b1541935bf92dfa06a0f00cd81b593ea438a9 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Sat, 16 Jul 2016 15:19:28 +0200
Subject: [PATCH] Add missing non-const reverse method in VectorwiseOp.

---
 Eigen/src/Core/VectorwiseOp.h | 11 ++++++++++-
 test/array_reverse.cpp        |  2 --
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/Eigen/src/Core/VectorwiseOp.h b/Eigen/src/Core/VectorwiseOp.h
index 00a4a8c39..dd382e990 100644
--- a/Eigen/src/Core/VectorwiseOp.h
+++ b/Eigen/src/Core/VectorwiseOp.h
@@ -284,6 +284,7 @@ template<typename ExpressionType, int Direction> class VectorwiseOp
     typedef typename ReturnType<internal::member_any>::Type AnyReturnType;
     typedef PartialReduxExpr<ExpressionType, internal::member_count<Index>, Direction> CountReturnType;
     typedef typename ReturnType<internal::member_prod>::Type ProdReturnType;
+    typedef Reverse<const ExpressionType, Direction> ConstReverseReturnType;
     typedef Reverse<ExpressionType, Direction> ReverseReturnType;
 
     template<int p> struct LpNormReturnType {
@@ -456,7 +457,15 @@ template<typename ExpressionType, int Direction> class VectorwiseOp
       *
       * \sa DenseBase::reverse() */
     EIGEN_DEVICE_FUNC
-    const ReverseReturnType reverse() const
+    const ConstReverseReturnType reverse() const
+    { return ConstReverseReturnType( _expression() ); }
+
+    /** \returns a writable matrix expression
+      * where each column (or row) are reversed.
+      *
+      * \sa reverse() const */
+    EIGEN_DEVICE_FUNC
+    ReverseReturnType reverse()
     { return ReverseReturnType( _expression() ); }
 
     typedef Replicate<ExpressionType,(isVertical?Dynamic:1),(isHorizontal?Dynamic:1)> ReplicateReturnType;
diff --git a/test/array_reverse.cpp b/test/array_reverse.cpp
index a5c0d37f9..c9d9f90c3 100644
--- a/test/array_reverse.cpp
+++ b/test/array_reverse.cpp
@@ -117,13 +117,11 @@ template<typename MatrixType> void reverse(const MatrixType& m)
   m2.colwise().reverseInPlace();
   VERIFY_IS_APPROX(m2,m1.colwise().reverse().eval());
 
-  /*
   m1.colwise().reverse()(r, c) = x;
   VERIFY_IS_APPROX(x, m1(rows - 1 - r, c));
 
   m1.rowwise().reverse()(r, c) = x;
   VERIFY_IS_APPROX(x, m1(r, cols - 1 - c));
-  */
 }
 
 void test_array_reverse()