fix Matrix::stride for vectors, add a unit test for Block::stride

and make use of it where it was relevant

2 files changed, 19 insertions, 10 deletions

diff --git a/Eigen/src/Core/Matrix.h b/Eigen/src/Core/Matrix.h
index f58424ba2..d0603871a 100644
--- a/Eigen/src/Core/Matrix.h
+++ b/Eigen/src/Core/Matrix.h
@@ -142,12 +142,21 @@ class Matrix
     EIGEN_STRONG_INLINE int rows() const { return m_storage.rows(); }
     EIGEN_STRONG_INLINE int cols() const { return m_storage.cols(); }
 
-    EIGEN_STRONG_INLINE int stride(void) const
+    /** Returns the leading dimension (for matrices) or the increment (for vectors) to be used with data().
+      *
+      * More precisely:
+      *  - for a column major matrix it returns the number of elements between two successive columns
+      *  - for a row major matrix it returns the number of elements between two successive rows
+      *  - for a vector it returns the number of elements between two successive coefficients
+      * This function has to be used together with the MapBase::data() function.
+      *
+      * \sa Matrix::data() */
+    EIGEN_STRONG_INLINE int stride() const
     {
-      if(Flags & RowMajorBit)
-        return m_storage.cols();
+      if(IsVectorAtCompileTime)
+        return 1;
       else
-        return m_storage.rows();
+        return (Flags & RowMajorBit) ? m_storage.cols() : m_storage.rows();
     }
 
     EIGEN_STRONG_INLINE const Scalar& coeff(int row, int col) const
diff --git a/Eigen/src/Core/products/SelfadjointMatrixVector.h b/Eigen/src/Core/products/SelfadjointMatrixVector.h
index c2c33d5b8..d5927307d 100644
--- a/Eigen/src/Core/products/SelfadjointMatrixVector.h
+++ b/Eigen/src/Core/products/SelfadjointMatrixVector.h
@@ -185,14 +185,14 @@ struct SelfadjointProductMatrix<Lhs,LhsMode,false,Rhs,0,true>
     Scalar actualAlpha = alpha * LhsBlasTraits::extractScalarFactor(m_lhs)
                                * RhsBlasTraits::extractScalarFactor(m_rhs);
 
-    ei_assert((&dst.coeff(1))-(&dst.coeff(0))==1 && "not implemented yet");
+    ei_assert(dst.stride()==1 && "not implemented yet");
     ei_product_selfadjoint_vector<Scalar, ei_traits<_ActualLhsType>::Flags&RowMajorBit, int(LhsUpLo), bool(LhsBlasTraits::NeedToConjugate), bool(RhsBlasTraits::NeedToConjugate)>
       (
-        lhs.rows(),                                     // size
-        &lhs.coeff(0,0), lhs.stride(),                  // lhs info
-        &rhs.coeff(0), (&rhs.coeff(1))-(&rhs.coeff(0)), // rhs info
-        &dst.coeffRef(0),                               // result info
-        actualAlpha                                     // scale factor
+        lhs.rows(),                       // size
+        &lhs.coeff(0,0),  lhs.stride(),   // lhs info
+        &rhs.coeff(0),    rhs.stride(),   // rhs info
+        &dst.coeffRef(0),                 // result info
+        actualAlpha                       // scale factor
       );
   }
 };