From 7f0484502328c1ee0ed6a3916d7f3aa4417237c1 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Thu, 22 Dec 2011 11:53:47 +0100
Subject: [PATCH] fix assignment of a row-major sparse vector to a column major
 sparse one

---
 Eigen/src/SparseCore/SparseVector.h | 33 ++++++++++++++++++++++++++---
 1 file changed, 30 insertions(+), 3 deletions(-)

diff --git a/Eigen/src/SparseCore/SparseVector.h b/Eigen/src/SparseCore/SparseVector.h
index 741768109..ea83eab1a 100644
--- a/Eigen/src/SparseCore/SparseVector.h
+++ b/Eigen/src/SparseCore/SparseVector.h
@@ -53,7 +53,7 @@ struct traits<SparseVector<_Scalar, _Options, _Index> >
     ColsAtCompileTime = IsColVector ? 1 : Dynamic,
     MaxRowsAtCompileTime = RowsAtCompileTime,
     MaxColsAtCompileTime = ColsAtCompileTime,
-    Flags = _Options | NestByRefBit | LvalueBit,
+    Flags = _Options | NestByRefBit | LvalueBit | (IsColVector ? 0 : RowMajorBit),
     CoeffReadCost = NumTraits<Scalar>::ReadCost,
     SupportedAccessPatterns = InnerRandomAccessPattern
   };
@@ -242,9 +242,9 @@ class SparseVector
     inline SparseVector& operator=(const SparseMatrixBase<OtherDerived>& other)
     {
       if (int(RowsAtCompileTime)!=int(OtherDerived::RowsAtCompileTime))
-        return Base::operator=(other.transpose());
+        return assign(other.transpose());
       else
-        return Base::operator=(other);
+        return assign(other);
     }
 
     #ifndef EIGEN_PARSED_BY_DOXYGEN
@@ -311,6 +311,33 @@ class SparseVector
 #   ifdef EIGEN_SPARSEVECTOR_PLUGIN
 #     include EIGEN_SPARSEVECTOR_PLUGIN
 #   endif
+
+protected:
+    template<typename OtherDerived>
+    EIGEN_DONT_INLINE SparseVector& assign(const SparseMatrixBase<OtherDerived>& _other)
+    {
+      const OtherDerived& other(_other.derived());
+      const bool needToTranspose = (Flags & RowMajorBit) != (OtherDerived::Flags & RowMajorBit);
+      if(needToTranspose)
+      {
+        Index size = other.innerSize();
+        Index nnz = other.nonZeros();
+        resize(size);
+        reserve(nnz);
+        for(Index i=0; i<size; ++i)
+        {
+          typename OtherDerived::InnerIterator it(other, i);
+          if(it)
+              insert(i) = it.value();
+        }
+        return *this;
+      }
+      else
+      {
+        // there is no special optimization
+        return Base::operator=(other);
+      }
+    }
 };
 
 template<typename Scalar, int _Options, typename _Index>