Add .perpendicular() function in Geometry module (adapted from Eigen1)

Documentation:
 * add an overview for each module.
 * add an example for .all() and Cwise::operator<

Eigen/src/Array/AllAndAny.h

@@ -81,7 +81,12 @@ struct ei_any_unroller<Derived, Dynamic>
   * 
   * \returns true if all coefficients are true
   *
-  * \sa MatrixBase::any()
+  * \addexample CwiseAll \label How to check whether a point is inside a box (using operator< and all())
+  *
+  * Example: \include MatrixBase_all.cpp
+  * Output: \verbinclude MatrixBase_all.out
+  *
+  * \sa MatrixBase::any(), Cwise::operator<()
   */
 template<typename Derived>
 bool MatrixBase<Derived>::all(void) const
@@ -105,7 +110,7 @@ bool MatrixBase<Derived>::all(void) const
   * 
   * \returns true if at least one coefficient is true
   *
-  * \sa MatrixBase::any()
+  * \sa MatrixBase::all()
   */
 template<typename Derived>
 bool MatrixBase<Derived>::any(void) const

Eigen/src/Array/CwiseOperators.h

@@ -127,6 +127,8 @@ Cwise<ExpressionType>::cube() const
   * 
   * \returns an expression of the coefficient-wise \< operator of *this and \a other
   *
+  * See MatrixBase::all() for an example.
+  *
   * \sa class CwiseBinaryOp
   */
 template<typename ExpressionType>
@@ -155,6 +157,8 @@ Cwise<ExpressionType>::operator<=(const MatrixBase<OtherDerived> &other) const
   * 
   * \returns an expression of the coefficient-wise \> operator of *this and \a other
   *
+  * See MatrixBase::all() for an example.
+  *
   * \sa class CwiseBinaryOp
   */
 template<typename ExpressionType>
@@ -208,7 +212,8 @@ Cwise<ExpressionType>::operator!=(const MatrixBase<OtherDerived> &other) const
 }
 
 
-/** \returns an expression of \c *this with each coeff incremented by the constant \a scalar */
+/** \array_module
+  * \returns an expression of \c *this with each coeff incremented by the constant \a scalar */
 template<typename ExpressionType>
 inline const typename Cwise<ExpressionType>::ScalarAddReturnType
 Cwise<ExpressionType>::operator+(const Scalar& scalar) const
@@ -216,14 +221,16 @@ Cwise<ExpressionType>::operator+(const Scalar& scalar) const
   return typename Cwise<ExpressionType>::ScalarAddReturnType(m_matrix, ei_scalar_add_op<Scalar>(scalar));
 }
 
-/** \see operator+ */
+/** \array_module
+  * \see operator+() */
 template<typename ExpressionType>
 inline ExpressionType& Cwise<ExpressionType>::operator+=(const Scalar& scalar)
 {
   return m_matrix.const_cast_derived() = *this + scalar;
 }
 
-/** \returns an expression of \c *this with each coeff decremented by the constant \a scalar */
+/** \array_module
+  * \returns an expression of \c *this with each coeff decremented by the constant \a scalar */
 template<typename ExpressionType>
 inline const typename Cwise<ExpressionType>::ScalarAddReturnType
 Cwise<ExpressionType>::operator-(const Scalar& scalar) const
@@ -231,7 +238,8 @@ Cwise<ExpressionType>::operator-(const Scalar& scalar) const
   return *this + (-scalar);
 }
 
-/** \see operator- */
+/** \array_module
+  * \see operator- */
 template<typename ExpressionType>
 inline ExpressionType& Cwise<ExpressionType>::operator-=(const Scalar& scalar)
 {

Eigen/src/Array/PartialRedux.h

@@ -26,7 +26,7 @@
 #ifndef EIGEN_PARTIAL_REDUX_H
 #define EIGEN_PARTIAL_REDUX_H
 
-/** \array_module
+/** \array_module \ingroup Array
   * 
   * \class PartialReduxExpr
   *
@@ -128,7 +128,7 @@ struct ei_member_redux {
   const BinaryOp m_functor;
 };
 
-/** \array_module
+/** \array_module \ingroup Array
   *
   * \class PartialRedux
   *
@@ -141,7 +141,7 @@ struct ei_member_redux {
   * It is the return type of MatrixBase::colwise() and MatrixBase::rowwise()
   * and most of the time this is the only way it is used.
   *
-  * \sa MatrixBase::colwise(), MatrixBase::rowwise()
+  * \sa MatrixBase::colwise(), MatrixBase::rowwise(), class PartialReduxExpr
   */
 template<typename ExpressionType, int Direction> class PartialRedux
 {
@@ -236,9 +236,7 @@ MatrixBase<Derived>::rowwise() const
   return derived();
 }
 
-/** \array_module
-  * 
-  * \returns a row or column vector expression of \c *this reduxed by \a func
+/** \returns a row or column vector expression of \c *this reduxed by \a func
   *
   * The template parameter \a BinaryOp is the type of the functor
   * of the custom redux operator. Note that func must be an associative operator.

Eigen/src/Array/Random.h

@@ -49,7 +49,7 @@ struct ei_functor_traits<ei_scalar_random_op<Scalar> >
   * Example: \include MatrixBase_random_int_int.cpp
   * Output: \verbinclude MatrixBase_random_int_int.out
   *
-  * \sa ei_random(), ei_random(int)
+  * \sa MatrixBase::setRandom(), MatrixBase::Random(int), MatrixBase::Random()
   */
 template<typename Derived>
 inline const CwiseNullaryOp<ei_scalar_random_op<typename ei_traits<Derived>::Scalar>, Derived>
@@ -74,7 +74,7 @@ MatrixBase<Derived>::Random(int rows, int cols)
   * Example: \include MatrixBase_random_int.cpp
   * Output: \verbinclude MatrixBase_random_int.out
   *
-  * \sa ei_random(), ei_random(int,int)
+  * \sa MatrixBase::setRandom(), MatrixBase::Random(int,int), MatrixBase::Random()
   */
 template<typename Derived>
 inline const CwiseNullaryOp<ei_scalar_random_op<typename ei_traits<Derived>::Scalar>, Derived>
@@ -94,7 +94,7 @@ MatrixBase<Derived>::Random(int size)
   * Example: \include MatrixBase_random.cpp
   * Output: \verbinclude MatrixBase_random.out
   *
-  * \sa ei_random(int), ei_random(int,int)
+  * \sa MatrixBase::setRandom(), MatrixBase::Random(int,int), MatrixBase::Random(int)
   */
 template<typename Derived>
 inline const CwiseNullaryOp<ei_scalar_random_op<typename ei_traits<Derived>::Scalar>, Derived>
@@ -110,7 +110,7 @@ MatrixBase<Derived>::Random()
   * Example: \include MatrixBase_setRandom.cpp
   * Output: \verbinclude MatrixBase_setRandom.out
   *
-  * \sa class CwiseNullaryOp, ei_random()
+  * \sa class CwiseNullaryOp, MatrixBase::setRandom(int,int)
   */
 template<typename Derived>
 inline Derived& MatrixBase<Derived>::setRandom()