* #define EIGEN_NDEBUG now also disables asserts. Useful

to disable eigen's asserts without disabling one's own program's
  asserts. Notice that Eigen code should now use ei_assert()
  instead of assert().
* Remove findBiggestCoeff() as it's now almost redundant.
* Improve echelon.cpp: inner for loop replaced by xprs.
* remove useless "(*this)." here and there. I think they were
  first introduced by automatic search&replace.
* fix compilation in Visitor.h (issue triggered by echelon.cpp)
* improve comment on swap().

Eigen/src/Core/Block.h

@@ -90,7 +90,7 @@ template<typename MatrixType, int BlockRows, int BlockCols> class Block
         m_blockRows(matrix.rows()), // if it is a row, then m_blockRows has a fixed-size of 1, so no pb to try to overwrite it
         m_blockCols(matrix.cols())  // same for m_blockCols
     {
-      assert( (i>=0) && (
+      ei_assert( (i>=0) && (
           ((BlockRows==1) && (BlockCols==MatrixType::ColsAtCompileTime) && i<matrix.rows())
         ||((BlockRows==MatrixType::RowsAtCompileTime) && (BlockCols==1) && i<matrix.cols())));
     }
@@ -100,8 +100,8 @@ template<typename MatrixType, int BlockRows, int BlockCols> class Block
     Block(const MatrixType& matrix, int startRow, int startCol)
       : m_matrix(matrix), m_startRow(startRow), m_startCol(startCol)
     {
-      assert(RowsAtCompileTime!=Dynamic && RowsAtCompileTime!=Dynamic);
+      ei_assert(RowsAtCompileTime!=Dynamic && RowsAtCompileTime!=Dynamic);
-      assert(startRow >= 0 && BlockRows >= 1 && startRow + BlockRows <= matrix.rows()
+      ei_assert(startRow >= 0 && BlockRows >= 1 && startRow + BlockRows <= matrix.rows()
           && startCol >= 0 && BlockCols >= 1 && startCol + BlockCols <= matrix.cols());
     }
 
@@ -113,9 +113,9 @@ template<typename MatrixType, int BlockRows, int BlockCols> class Block
       : m_matrix(matrix), m_startRow(startRow), m_startCol(startCol),
                           m_blockRows(blockRows), m_blockCols(blockCols)
     {
-      assert((RowsAtCompileTime==Dynamic || RowsAtCompileTime==1)
+      ei_assert((RowsAtCompileTime==Dynamic || RowsAtCompileTime==1)
           && (ColsAtCompileTime==Dynamic || ColsAtCompileTime==1));
-      assert(startRow >= 0 && blockRows >= 1 && startRow + blockRows <= matrix.rows()
+      ei_assert(startRow >= 0 && blockRows >= 1 && startRow + blockRows <= matrix.rows()
           && startCol >= 0 && blockCols >= 1 && startCol + blockCols <= matrix.cols());
     }
 
@@ -197,7 +197,7 @@ template<typename Derived>
 Block<Derived> MatrixBase<Derived>
   ::block(int start, int size)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   return Block<Derived>(derived(), RowsAtCompileTime == 1 ? 0 : start,
                                    ColsAtCompileTime == 1 ? 0 : start,
                                    RowsAtCompileTime == 1 ? 1 : size,
@@ -209,7 +209,7 @@ template<typename Derived>
 const Block<Derived> MatrixBase<Derived>
   ::block(int start, int size) const
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   return Block<Derived>(derived(), RowsAtCompileTime == 1 ? 0 : start,
                                    ColsAtCompileTime == 1 ? 0 : start,
                                    RowsAtCompileTime == 1 ? 1 : size,
@@ -235,7 +235,7 @@ template<typename Derived>
 Block<Derived> MatrixBase<Derived>
   ::start(int size)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   return Block<Derived>(derived(), 0, 0,
                         RowsAtCompileTime == 1 ? 1 : size,
                         ColsAtCompileTime == 1 ? 1 : size);
@@ -246,7 +246,7 @@ template<typename Derived>
 const Block<Derived> MatrixBase<Derived>
   ::start(int size) const
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   return Block<Derived>(derived(), 0, 0,
                         RowsAtCompileTime == 1 ? 1 : size,
                         ColsAtCompileTime == 1 ? 1 : size);
@@ -271,7 +271,7 @@ template<typename Derived>
 Block<Derived> MatrixBase<Derived>
   ::end(int size)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   return Block<Derived>(derived(),
                         RowsAtCompileTime == 1 ? 0 : rows() - size,
                         ColsAtCompileTime == 1 ? 0 : cols() - size,
@@ -284,7 +284,7 @@ template<typename Derived>
 const Block<Derived> MatrixBase<Derived>
   ::end(int size) const
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   return Block<Derived>(derived(),
                         RowsAtCompileTime == 1 ? 0 : rows() - size,
                         ColsAtCompileTime == 1 ? 0 : cols() - size,

Eigen/src/Core/Coeffs.h

@@ -43,7 +43,7 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar MatrixBase<Derived>
   ::coeff(int row, int col) const
 {
-  eigen_internal_assert(row >= 0 && row < rows()
+  ei_internal_assert(row >= 0 && row < rows()
                      && col >= 0 && col < cols());
   return derived()._coeff(row, col);
 }
@@ -56,7 +56,7 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar MatrixBase<Derived>
   ::operator()(int row, int col) const
 {
-  assert(row >= 0 && row < rows()
+  ei_assert(row >= 0 && row < rows()
       && col >= 0 && col < cols());
   return derived()._coeff(row, col);
 }
@@ -79,7 +79,7 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar& MatrixBase<Derived>
   ::coeffRef(int row, int col)
 {
-  eigen_internal_assert(row >= 0 && row < rows()
+  ei_internal_assert(row >= 0 && row < rows()
                      && col >= 0 && col < cols());
   return derived()._coeffRef(row, col);
 }
@@ -92,7 +92,7 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar& MatrixBase<Derived>
   ::operator()(int row, int col)
 {
-  assert(row >= 0 && row < rows()
+  ei_assert(row >= 0 && row < rows()
       && col >= 0 && col < cols());
   return derived()._coeffRef(row, col);
 }
@@ -115,15 +115,15 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar MatrixBase<Derived>
   ::coeff(int index) const
 {
-  eigen_internal_assert(IsVectorAtCompileTime);
+  ei_internal_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1)
   {
-    eigen_internal_assert(index >= 0 && index < cols());
+    ei_internal_assert(index >= 0 && index < cols());
     return coeff(0, index);
   }
   else
   {
-    eigen_internal_assert(index >= 0 && index < rows());
+    ei_internal_assert(index >= 0 && index < rows());
     return coeff(index, 0);
   }
 }
@@ -139,15 +139,15 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar MatrixBase<Derived>
   ::operator[](int index) const
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1)
   {
-    assert(index >= 0 && index < cols());
+    ei_assert(index >= 0 && index < cols());
     return coeff(0, index);
   }
   else
   {
-    assert(index >= 0 && index < rows());
+    ei_assert(index >= 0 && index < rows());
     return coeff(index, 0);
   }
 }
@@ -170,15 +170,15 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar& MatrixBase<Derived>
   ::coeffRef(int index)
 {
-  eigen_internal_assert(IsVectorAtCompileTime);
+  ei_internal_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1)
   {
-    eigen_internal_assert(index >= 0 && index < cols());
+    ei_internal_assert(index >= 0 && index < cols());
     return coeffRef(0, index);
   }
   else
   {
-    eigen_internal_assert(index >= 0 && index < rows());
+    ei_internal_assert(index >= 0 && index < rows());
     return coeffRef(index, 0);
   }
 }
@@ -193,15 +193,15 @@ template<typename Derived>
 typename ei_traits<Derived>::Scalar& MatrixBase<Derived>
   ::operator[](int index)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1)
   {
-    assert(index >= 0 && index < cols());
+    ei_assert(index >= 0 && index < cols());
     return coeffRef(0, index);
   }
   else
   {
-    assert(index >= 0 && index < rows());
+    ei_assert(index >= 0 && index < rows());
     return coeffRef(index, 0);
   }
 }

Eigen/src/Core/CommaInitializer.h

@@ -52,12 +52,12 @@ struct MatrixBase<Derived>::CommaInitializer
       m_row+=m_currentBlockRows;
       m_col = 0;
       m_currentBlockRows = 1;
-      assert(m_row<m_matrix.rows()
+      ei_assert(m_row<m_matrix.rows()
         && "Too many rows passed to MatrixBase::operator<<");
     }
-    assert(m_col<m_matrix.cols()
+    ei_assert(m_col<m_matrix.cols()
       && "Too many coefficients passed to MatrixBase::operator<<");
-    assert(m_currentBlockRows==1);
+    ei_assert(m_currentBlockRows==1);
     m_matrix.coeffRef(m_row, m_col++) = s;
     return *this;
   }
@@ -70,12 +70,12 @@ struct MatrixBase<Derived>::CommaInitializer
       m_row+=m_currentBlockRows;
       m_col = 0;
       m_currentBlockRows = other.rows();
-      assert(m_row+m_currentBlockRows<=m_matrix.rows()
+      ei_assert(m_row+m_currentBlockRows<=m_matrix.rows()
         && "Too many rows passed to MatrixBase::operator<<");
     }
-    assert(m_col<m_matrix.cols()
+    ei_assert(m_col<m_matrix.cols()
       && "Too many coefficients passed to MatrixBase::operator<<");
-    assert(m_currentBlockRows==other.rows());
+    ei_assert(m_currentBlockRows==other.rows());
     if (OtherDerived::RowsAtCompileTime>0 && OtherDerived::ColsAtCompileTime>0)
       m_matrix.block< (OtherDerived::RowsAtCompileTime>0?OtherDerived::RowsAtCompileTime:1) ,
                       (OtherDerived::ColsAtCompileTime>0?OtherDerived::ColsAtCompileTime:1) >(m_row, m_col) = other;
@@ -87,7 +87,7 @@ struct MatrixBase<Derived>::CommaInitializer
 
   ~CommaInitializer(void)
   {
-    assert((m_row+m_currentBlockRows) == m_matrix.rows()
+    ei_assert((m_row+m_currentBlockRows) == m_matrix.rows()
          && m_col == m_matrix.cols()
          && "Too few coefficients passed to Matrix::operator<<");
   }

Eigen/src/Core/CwiseBinaryOp.h

@@ -74,7 +74,7 @@ class CwiseBinaryOp : ei_no_assignment_operator,
     CwiseBinaryOp(const Lhs& lhs, const Rhs& rhs, const BinaryOp& func = BinaryOp())
       : m_lhs(lhs), m_rhs(rhs), m_functor(func)
     {
-      assert(lhs.rows() == rhs.rows() && lhs.cols() == rhs.cols());
+      ei_assert(lhs.rows() == rhs.rows() && lhs.cols() == rhs.cols());
     }
 
   private:

Eigen/src/Core/DiagonalMatrix.h

@@ -60,7 +60,7 @@ class DiagonalMatrix : ei_no_assignment_operator,
 
     DiagonalMatrix(const CoeffsVectorType& coeffs) : m_coeffs(coeffs)
     {
-      assert(CoeffsVectorType::IsVectorAtCompileTime
+      ei_assert(CoeffsVectorType::IsVectorAtCompileTime
           && coeffs.size() > 0);
     }
 

Eigen/src/Core/Dot.h

@@ -72,7 +72,7 @@ template<typename OtherDerived>
 typename ei_traits<Derived>::Scalar
 MatrixBase<Derived>::dot(const MatrixBase<OtherDerived>& other) const
 {
-  assert(IsVectorAtCompileTime
+  ei_assert(IsVectorAtCompileTime
       && OtherDerived::IsVectorAtCompileTime
       && size() == other.size());
   Scalar res;

Eigen/src/Core/Fuzzy.h

@@ -48,7 +48,7 @@ bool MatrixBase<Derived>::isApprox(
   typename NumTraits<Scalar>::Real prec
 ) const
 {
-  assert(rows() == other.rows() && cols() == other.cols());
+  ei_assert(rows() == other.rows() && cols() == other.cols());
   if(IsVectorAtCompileTime)
   {
     return((*this - other).norm2() <= std::min(norm2(), other.norm2()) * prec * prec);
@@ -109,7 +109,7 @@ bool MatrixBase<Derived>::isMuchSmallerThan(
   typename NumTraits<Scalar>::Real prec
 ) const
 {
-  assert(rows() == other.rows() && cols() == other.cols());
+  ei_assert(rows() == other.rows() && cols() == other.cols());
   if(IsVectorAtCompileTime)
   {
     return(norm2() <= other.norm2() * prec * prec);

Eigen/src/Core/Identity.h

@@ -52,7 +52,7 @@ template<typename MatrixType> class Identity : ei_no_assignment_operator,
 
     Identity(int rows, int cols) : m_rows(rows), m_cols(cols)
     {
-      assert(rows > 0
+      ei_assert(rows > 0
           && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
           && cols > 0
           && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == cols));

Eigen/src/Core/Map.h

@@ -81,7 +81,7 @@ template<typename MatrixType> class Map
   public:
     Map(const Scalar* data, int rows, int cols) : m_data(data), m_rows(rows), m_cols(cols)
     {
-      assert(rows > 0
+      ei_assert(rows > 0
           && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
           && cols > 0
           && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == cols));
@@ -107,7 +107,7 @@ template<typename _Scalar, int _Rows, int _Cols, int _StorageOrder, int _MaxRows
 const Map<Matrix<_Scalar, _Rows, _Cols, _StorageOrder, _MaxRows, _MaxCols> >
 Matrix<_Scalar, _Rows, _Cols, _StorageOrder, _MaxRows, _MaxCols>::map(const Scalar* data, int size)
 {
-  assert(_Cols == 1 || _Rows ==1);
+  ei_assert(_Cols == 1 || _Rows ==1);
   if(_Cols == 1)
     return Map<Matrix>(data, size, 1);
   else
@@ -156,7 +156,7 @@ template<typename _Scalar, int _Rows, int _Cols, int _StorageOrder, int _MaxRows
 Map<Matrix<_Scalar, _Rows, _Cols, _StorageOrder, _MaxRows, _MaxCols> >
 Matrix<_Scalar, _Rows, _Cols, _StorageOrder, _MaxRows, _MaxCols>::map(Scalar* data, int size)
 {
-  assert(_Cols == 1 || _Rows ==1);
+  ei_assert(_Cols == 1 || _Rows ==1);
   if(_Cols == 1)
     return Map<Matrix>(data, size, 1);
   else

Eigen/src/Core/MathFunctions.h

@@ -35,11 +35,11 @@ inline int ei_imag(int)    { return 0; }
 inline int ei_conj(int x)  { return x; }
 inline int ei_abs(int x)   { return abs(x); }
 inline int ei_abs2(int x)  { return x*x; }
-inline int ei_sqrt(int)  { assert(false); return 0; }
+inline int ei_sqrt(int)  { ei_assert(false); return 0; }
-inline int ei_exp(int)  { assert(false); return 0; }
+inline int ei_exp(int)  { ei_assert(false); return 0; }
-inline int ei_log(int)  { assert(false); return 0; }
+inline int ei_log(int)  { ei_assert(false); return 0; }
-inline int ei_sin(int)  { assert(false); return 0; }
+inline int ei_sin(int)  { ei_assert(false); return 0; }
-inline int ei_cos(int)  { assert(false); return 0; }
+inline int ei_cos(int)  { ei_assert(false); return 0; }
 #if (defined __ICC) || (defined __GNUC__ && (__GNUC__<4 || __GNUC_MINOR__<3))
 inline int ei_pow(int x, int y) { return int(std::pow(double(x), y)); }
 #else

Eigen/src/Core/Matrix.h

@@ -131,7 +131,7 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
 
     void resize(int rows, int cols)
     {
-      assert(rows > 0
+      ei_assert(rows > 0
           && (MaxRowsAtCompileTime == Dynamic || MaxRowsAtCompileTime >= rows)
           && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
           && cols > 0
@@ -153,12 +153,12 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
     {
       if(RowsAtCompileTime == 1)
       {
-        assert(other.isVector());
+        ei_assert(other.isVector());
         resize(1, other.size());
       }
       else if(ColsAtCompileTime == 1)
       {
-        assert(other.isVector());
+        ei_assert(other.isVector());
         resize(other.size(), 1);
       }
       else resize(other.rows(), other.cols());
@@ -191,7 +191,7 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
       */
     explicit Matrix()
     {
-      assert(RowsAtCompileTime > 0 && ColsAtCompileTime > 0);
+      ei_assert(RowsAtCompileTime > 0 && ColsAtCompileTime > 0);
     }
 
     /** Constructs a vector or row-vector with given dimension. \only_for_vectors
@@ -202,8 +202,8 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
       */
     explicit Matrix(int dim) : m_storage(dim, RowsAtCompileTime == 1 ? 1 : dim, ColsAtCompileTime == 1 ? 1 : dim)
     {
-      assert(dim > 0);
+      ei_assert(dim > 0);
-      assert((RowsAtCompileTime == 1
+      ei_assert((RowsAtCompileTime == 1
               && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == dim))
           || (ColsAtCompileTime == 1
               && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == dim)));
@@ -229,14 +229,14 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
       }
       else
       {
-        assert(x > 0 && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == x)
+        ei_assert(x > 0 && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == x)
             && y > 0 && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == y));
       }
     }
     /** constructs an initialized 2D vector with given coefficients */
     Matrix(const float& x, const float& y)
     {
-      assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 2)
+      ei_assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 2)
           || (RowsAtCompileTime == 2 && ColsAtCompileTime == 1));
       m_storage.data()[0] = x;
       m_storage.data()[1] = y;
@@ -244,7 +244,7 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
     /** constructs an initialized 2D vector with given coefficients */
     Matrix(const double& x, const double& y)
     {
-      assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 2)
+      ei_assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 2)
           || (RowsAtCompileTime == 2 && ColsAtCompileTime == 1));
       m_storage.data()[0] = x;
       m_storage.data()[1] = y;
@@ -252,7 +252,7 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
     /** constructs an initialized 3D vector with given coefficients */
     Matrix(const Scalar& x, const Scalar& y, const Scalar& z)
     {
-      assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 3)
+      ei_assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 3)
           || (RowsAtCompileTime == 3 && ColsAtCompileTime == 1));
       m_storage.data()[0] = x;
       m_storage.data()[1] = y;
@@ -261,7 +261,7 @@ class Matrix : public MatrixBase<Matrix<_Scalar, _Rows, _Cols,
     /** constructs an initialized 4D vector with given coefficients */
     Matrix(const Scalar& x, const Scalar& y, const Scalar& z, const Scalar& w)
     {
-      assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 4)
+      ei_assert((RowsAtCompileTime == 1 && ColsAtCompileTime == 4)
           || (RowsAtCompileTime == 4 && ColsAtCompileTime == 1));
       m_storage.data()[0] = x;
       m_storage.data()[1] = y;

Eigen/src/Core/MatrixBase.h

@@ -343,13 +343,6 @@ template<typename Derived> class MatrixBase
                  RealScalar prec = precision<Scalar>()) const;
     bool isOrtho(RealScalar prec = precision<Scalar>()) const;
 
-    /** puts in *row and *col the location of the coefficient of *this
-      * which has the biggest absolute value.
-      */
-    void findBiggestCoeff(int *row, int *col) const
-    { (*this).cwiseAbs().maxCoeff(row, col); }
-    //@}
-
     /// \name Special functions
     //@{
     template<typename NewType>
@@ -358,12 +351,6 @@ template<typename Derived> class MatrixBase
     const Eval<Derived> eval() const EIGEN_ALWAYS_INLINE;
     const EvalOMP<Derived> evalOMP() const EIGEN_ALWAYS_INLINE;
 
-    /** swaps *this with the expression \a other.
-      *
-      * \note \a other is only marked const because I couln't find another way
-      * to get g++ 4.2 to accept that template parameter resolution. It gets const_cast'd
-      * of course. TODO: get rid of const here.
-      */
     template<typename OtherDerived>
     void swap(const MatrixBase<OtherDerived>& other);
     //@}

Eigen/src/Core/Minor.h

@@ -64,7 +64,7 @@ template<typename MatrixType> class Minor
                 int row, int col)
       : m_matrix(matrix), m_row(row), m_col(col)
     {
-      assert(row >= 0 && row < matrix.rows()
+      ei_assert(row >= 0 && row < matrix.rows()
           && col >= 0 && col < matrix.cols());
     }
 

Eigen/src/Core/Ones.h

@@ -64,7 +64,7 @@ template<typename MatrixType> class Ones : ei_no_assignment_operator,
   public:
     Ones(int rows, int cols) : m_rows(rows), m_cols(cols)
     {
-      assert(rows > 0
+      ei_assert(rows > 0
           && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
           && cols > 0
           && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == cols));
@@ -114,7 +114,7 @@ const Ones<Derived> MatrixBase<Derived>::ones(int rows, int cols)
 template<typename Derived>
 const Ones<Derived> MatrixBase<Derived>::ones(int size)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1) return Ones<Derived>(1, size);
   else return Ones<Derived>(size, 1);
 }

Eigen/src/Core/OperatorEquals.h

@@ -105,7 +105,7 @@ Derived& MatrixBase<Derived>
   if(IsVectorAtCompileTime && OtherDerived::IsVectorAtCompileTime)
     // copying a vector expression into a vector
   {
-    assert(size() == other.size());
+    ei_assert(size() == other.size());
     if(EIGEN_UNROLLED_LOOPS
     && SizeAtCompileTime != Dynamic
     && SizeAtCompileTime <= EIGEN_UNROLLING_LIMIT)
@@ -120,7 +120,7 @@ Derived& MatrixBase<Derived>
   }
   else // copying a matrix expression into a matrix
   {
-    assert(rows() == other.rows() && cols() == other.cols());
+    ei_assert(rows() == other.rows() && cols() == other.cols());
     if(EIGEN_UNROLLED_LOOPS
     && SizeAtCompileTime != Dynamic
     && SizeAtCompileTime <= EIGEN_UNROLLING_LIMIT)
@@ -148,7 +148,7 @@ Derived& MatrixBase<Derived>
             coeffRef(i, j) = other.coeff(i, j);
       }
     }
-    return (*this).derived();
+    return derived();
   }
 }
 

Eigen/src/Core/Product.h

@@ -106,7 +106,7 @@ template<typename Lhs, typename Rhs, int EvalMode> class Product : ei_no_assignm
     Product(const Lhs& lhs, const Rhs& rhs)
       : m_lhs(lhs), m_rhs(rhs)
     {
-      assert(lhs.cols() == rhs.rows());
+      ei_assert(lhs.cols() == rhs.rows());
     }
 
     /** \internal */
@@ -172,7 +172,7 @@ template<typename OtherDerived>
 const Eval<Product<Derived, OtherDerived> >
 MatrixBase<Derived>::operator*(const MatrixBase<OtherDerived> &other) const
 {
-  return (*this).lazyProduct(other).eval();
+  return lazyProduct(other).eval();
 }
 
 /** replaces \c *this by \c *this * \a other.
@@ -192,7 +192,7 @@ template<typename Derived1, typename Derived2>
 Derived& MatrixBase<Derived>::operator=(const Product<Derived1,Derived2,CacheOptimal>& product)
 {
   product._cacheOptimalEval(*this);
-  return (*this).derived();
+  return derived();
 }
 
 template<typename Lhs, typename Rhs, int EvalMode>

Eigen/src/Core/Random.h

@@ -65,7 +65,7 @@ template<typename MatrixType> class Random : ei_no_assignment_operator,
 
     Random(int rows, int cols) : m_rows(rows), m_cols(cols)
     {
-      assert(rows > 0
+      ei_assert(rows > 0
           && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
           && cols > 0
           && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == cols));
@@ -117,7 +117,7 @@ template<typename Derived>
 const Eval<Random<Derived> >
 MatrixBase<Derived>::random(int size)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1) return Random<Derived>(1, size).eval();
   else return Random<Derived>(size, 1).eval();
 }

Eigen/src/Core/Swap.h

@@ -25,6 +25,15 @@
 #ifndef EIGEN_SWAP_H
 #define EIGEN_SWAP_H
 
+/** swaps *this with the expression \a other.
+  *
+  * \note \a other is only marked const because I couln't find another way
+  * to get g++ (4.2 and 4.3) to accept that template parameter resolution.
+  * The problem seems to be that when swapping expressions as in
+  * m.row(i).swap(m.row(j)); the Row object returned by row(j) is a temporary
+  * and g++ doesn't dare to pass it by non-constant reference.
+  * It gets const_cast'd of course. TODO: get rid of const here.
+  */
 template<typename Derived>
 template<typename OtherDerived>
 void MatrixBase<Derived>::swap(const MatrixBase<OtherDerived>& other)
@@ -35,7 +44,7 @@ void MatrixBase<Derived>::swap(const MatrixBase<OtherDerived>& other)
     Scalar tmp;
     if(IsVectorAtCompileTime)
     {
-      assert(OtherDerived::IsVectorAtCompileTime && size() == _other->size());
+      ei_assert(OtherDerived::IsVectorAtCompileTime && size() == _other->size());
       for(int i = 0; i < size(); i++)
       {
         tmp = coeff(i);

Eigen/src/Core/Util.h

@@ -49,10 +49,16 @@ EIGEN_USING_MATRIX_TYPEDEFS \
 using Eigen::Matrix; \
 using Eigen::MatrixBase;
 
-#ifdef EIGEN_INTERNAL_DEBUGGING
+#ifdef EIGEN_NDEBUG
-#define eigen_internal_assert(x) assert(x);
+#define ei_assert(x)
 #else
-#define eigen_internal_assert(x)
+#define ei_assert(x) assert(x)
+#endif
+
+#ifdef EIGEN_INTERNAL_DEBUGGING
+#define ei_internal_assert(x) ei_assert(x);
+#else
+#define ei_internal_assert(x)
 #endif
 
 #ifdef NDEBUG

Eigen/src/Core/Visitor.h

@@ -82,13 +82,12 @@ void MatrixBase<Derived>::visit(Visitor& visitor) const
         SizeAtCompileTime : Dynamic>::run(derived(), visitor);
   else
   {
-    Scalar res;
     visitor.init(coeff(0,0), 0, 0);
     for(int i = 1; i < rows(); i++)
-      visitor(res, coeff(i, 0), i, 0);
+      visitor(coeff(i, 0), i, 0);
     for(int j = 1; j < cols(); j++)
       for(int i = 0; i < rows(); i++)
-        visitor(res, coeff(i, j), i, j);
+        visitor(coeff(i, j), i, j);
   }
 }
 

Eigen/src/Core/Zero.h

@@ -65,7 +65,7 @@ template<typename MatrixType> class Zero : ei_no_assignment_operator,
 
     Zero(int rows, int cols) : m_rows(rows), m_cols(cols)
     {
-      assert(rows > 0
+      ei_assert(rows > 0
           && (RowsAtCompileTime == Dynamic || RowsAtCompileTime == rows)
           && cols > 0
           && (ColsAtCompileTime == Dynamic || ColsAtCompileTime == cols));
@@ -115,7 +115,7 @@ const Zero<Derived> MatrixBase<Derived>::zero(int rows, int cols)
 template<typename Derived>
 const Zero<Derived> MatrixBase<Derived>::zero(int size)
 {
-  assert(IsVectorAtCompileTime);
+  ei_assert(IsVectorAtCompileTime);
   if(RowsAtCompileTime == 1) return Zero<Derived>(1, size);
   else return Zero<Derived>(size, 1);
 }

doc/echelon.cpp

@@ -7,19 +7,22 @@ namespace Eigen {
 template<typename Derived>
 void echelon(MatrixBase<Derived>& m)
 {
-  const int N = std::min(m.rows(), m.cols());
+  for(int k = 0; k < m.diagonal().size(); k++)
-
-  for(int k = 0; k < N; k++)
   {
     int rowOfBiggest, colOfBiggest;
-    int cornerRows = m.rows()-k;
+    int cornerRows = m.rows()-k, cornerCols = m.cols()-k;
-    int cornerCols = m.cols()-k;
     m.corner(BottomRight, cornerRows, cornerCols)
-     .findBiggestCoeff(&rowOfBiggest, &colOfBiggest);
+     .cwiseAbs()
+     .maxCoeff(&rowOfBiggest, &colOfBiggest);
     m.row(k).swap(m.row(k+rowOfBiggest));
     m.col(k).swap(m.col(k+colOfBiggest));
-    for(int r = k+1; r < m.rows(); r++)
+    // important performance tip:
-      m.row(r).end(cornerCols) -= m.row(k).end(cornerCols) * m(r,k) / m(k,k);
+    // in a complex expression such as below it can be very important to fine-tune
+    // exactly where evaluation occurs. The parentheses and .eval() below ensure
+    // that the quotient is computed only once, and that the evaluation caused
+    // by operator* occurs last.
+    m.corner(BottomRight, cornerRows-1, cornerCols)
+      -= m.col(k).end(cornerRows-1) * (m.row(k).end(cornerCols) / m(k,k)).eval();
   }
 }
 
@@ -65,6 +68,7 @@ int main(int, char **)
   cout << "Here's the matrix m:" << endl << m << endl;
 
   cout << "Now let's echelon m:" << endl;
+  for(int i = 0; i < 1000000; i++)
   echelon(m);
 
   cout << "Now m is:" << endl << m << endl;