* added a pseudo expression Array giving access to:

   - matrix-scalar addition/subtraction operators, e.g.:
       m.array() += 0.5;
   - matrix/matrix comparison operators, e.g.:
      if (m1.array() < m2.array()) {}
* fix compilation issues with Transform and gcc < 4.1

2 files changed, 187 insertions, 7 deletions

diff --git a/Eigen/src/Array/Array.h b/Eigen/src/Array/Array.h
new file mode 100644
index 000000000..5fd074e76
--- /dev/null
+++ b/Eigen/src/Array/Array.h
@@ -0,0 +1,152 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra. Eigen itself is part of the KDE project.
+//
+// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
+//
+// Eigen is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3 of the License, or (at your option) any later version.
+//
+// Alternatively, you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License and a copy of the GNU General Public License along with
+// Eigen. If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef EIGEN_ARRAY_H
+#define EIGEN_ARRAY_H
+
+/** \class Array
+  *
+  * \brief Pseudo expression offering additional features to an expression
+  *
+  * \param ExpressionType the type of the object of which we want array related features
+  *
+  * This class represents an expression with additional, array related, features.
+  * It is the return type of MatrixBase::array()
+  * and most of the time this is the only way it is used.
+  *
+  * \sa MatrixBase::array()
+  */
+template<typename ExpressionType> class Array
+{
+  public:
+
+    typedef typename ei_traits<ExpressionType>::Scalar Scalar;
+    typedef typename ei_meta_if<ei_must_nest_by_value<ExpressionType>::ret,
+        ExpressionType, const ExpressionType&>::ret ExpressionTypeNested;
+//     typedef NestByValue<typename ExpressionType::ConstantReturnType> ConstantReturnType;
+    typedef CwiseUnaryOp<ei_scalar_add_op<Scalar>, ExpressionType> ScalarAddReturnType;
+
+    inline Array(const ExpressionType& matrix) : m_matrix(matrix) {}
+
+    /** \internal */
+    inline const ExpressionType& _expression() const { return m_matrix; }
+
+    const ScalarAddReturnType
+    operator+(const Scalar& scalar) const;
+
+    /** \relates Array */
+    friend const ScalarAddReturnType
+    operator+(const Scalar& scalar, const Array& mat)
+    { return mat + scalar; }
+
+    ExpressionType& operator+=(const Scalar& scalar);
+
+    const ScalarAddReturnType
+    operator-(const Scalar& scalar) const;
+
+    ExpressionType& operator-=(const Scalar& scalar);
+
+    /** \returns true if each coeff of \c *this is less than its respective coeff of \a other */
+    template<typename OtherDerived> bool operator<(const Array<OtherDerived>& other) const
+    { return m_matrix.cwiseLessThan(other._expression()).all(); }
+
+    /** \returns true if each coeff of \c *this is less or equal to its respective coeff of \a other */
+    template<typename OtherDerived> bool operator<=(const Array<OtherDerived>& other) const
+    { return m_matrix.cwiseLessEqual(other._expression()).all(); }
+
+    /** \returns true if each coeff of \c *this is greater to its respective coeff of \a other */
+    template<typename OtherDerived>
+    bool operator>(const Array<OtherDerived>& other) const
+    { return m_matrix.cwiseGreaterThan(other._expression()).all(); }
+
+    /** \returns true if each coeff of \c *this is greater or equal to its respective coeff of \a other */
+    template<typename OtherDerived>
+    bool operator>=(const Array<OtherDerived>& other) const
+    { return m_matrix.cwiseGreaterEqual(other._expression()).all(); }
+
+  protected:
+    ExpressionTypeNested m_matrix;
+};
+
+/** \returns an expression of \c *this with each coeff incremented by the constant \a scalar */
+template<typename ExpressionType>
+const typename Array<ExpressionType>::ScalarAddReturnType
+Array<ExpressionType>::operator+(const Scalar& scalar) const
+{
+  return CwiseUnaryOp<ei_scalar_add_op<Scalar>, ExpressionType>(m_matrix, ei_scalar_add_op<Scalar>(scalar));
+}
+
+/** \see operator+ */
+template<typename ExpressionType>
+ExpressionType& Array<ExpressionType>::operator+=(const Scalar& scalar)
+{
+  m_matrix.const_cast_derived() = *this + scalar;
+  return m_matrix.const_cast_derived();
+}
+
+/** \returns an expression of \c *this with each coeff decremented by the constant \a scalar */
+template<typename ExpressionType>
+const typename Array<ExpressionType>::ScalarAddReturnType
+Array<ExpressionType>::operator-(const Scalar& scalar) const
+{
+  return *this + (-scalar);
+}
+
+/** \see operator- */
+template<typename ExpressionType>
+ExpressionType& Array<ExpressionType>::operator-=(const Scalar& scalar)
+{
+  m_matrix.const_cast_derived() = *this - scalar;
+  return m_matrix.const_cast_derived();
+}
+
+/** \array_module
+  *
+  * \returns an Array expression of *this providing additional,
+  * array related, features.
+  *
+  * \sa class Array
+  */
+template<typename Derived>
+inline const Array<Derived>
+MatrixBase<Derived>::array() const
+{
+  return derived();
+}
+
+/** \array_module
+  *
+  * \returns an Array expression of *this providing additional,
+  * array related, features.
+  *
+  * \sa class Array
+  */
+template<typename Derived>
+inline Array<Derived>
+MatrixBase<Derived>::array()
+{
+  return derived();
+}
+
+#endif // EIGEN_FLAGGED_H
diff --git a/Eigen/src/Array/Functors.h b/Eigen/src/Array/Functors.h
index 6a0a25a3a..03ae98090 100644
--- a/Eigen/src/Array/Functors.h
+++ b/Eigen/src/Array/Functors.h
@@ -26,9 +26,37 @@
 #define EIGEN_ARRAY_FUNCTORS_H
 
 /** \internal
+  * \array_module
+  *
+  * \brief Template functor to add a scalar to a fixed other one
+  *
+  * \sa class CwiseUnaryOp, Array::operator+
+  */
+template<typename Scalar, bool PacketAccess = (int(ei_packet_traits<Scalar>::size)>1?true:false) > struct ei_scalar_add_op;
+
+template<typename Scalar>
+struct ei_scalar_add_op<Scalar,true> {
+  typedef typename ei_packet_traits<Scalar>::type PacketScalar;
+  inline ei_scalar_add_op(const Scalar& other) : m_other(ei_pset1(other)) { }
+  inline Scalar operator() (const Scalar& a) const { return a + ei_pfirst(m_other); }
+  inline const PacketScalar packetOp(const PacketScalar& a) const
+  { return ei_padd(a, m_other); }
+  const PacketScalar m_other;
+};
+template<typename Scalar>
+struct ei_scalar_add_op<Scalar,false> {
+  inline ei_scalar_add_op(const Scalar& other) : m_other(other) { }
+  inline Scalar operator() (const Scalar& a) const { return a + m_other; }
+  const Scalar m_other;
+};
+template<typename Scalar>
+struct ei_functor_traits<ei_scalar_add_op<Scalar> >
+{ enum { Cost = NumTraits<Scalar>::AddCost, PacketAccess = ei_packet_traits<Scalar>::size>1 }; };
+
+/** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to compute the square root of a scalar
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwiseSqrt()
@@ -43,7 +71,7 @@ struct ei_functor_traits<ei_scalar_sqrt_op<Scalar> >
 /** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to compute the exponential of a scalar
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwiseExp()
@@ -58,7 +86,7 @@ struct ei_functor_traits<ei_scalar_exp_op<Scalar> >
 /** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to compute the logarithm of a scalar
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwiseLog()
@@ -73,7 +101,7 @@ struct ei_functor_traits<ei_scalar_log_op<Scalar> >
 /** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to compute the cosine of a scalar
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwiseCos()
@@ -88,7 +116,7 @@ struct ei_functor_traits<ei_scalar_cos_op<Scalar> >
 /** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to compute the sine of a scalar
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwiseSin()
@@ -103,7 +131,7 @@ struct ei_functor_traits<ei_scalar_sin_op<Scalar> >
 /** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to raise a scalar to a power
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwisePow
@@ -121,7 +149,7 @@ struct ei_functor_traits<ei_scalar_pow_op<Scalar> >
 /** \internal
   *
   * \array_module
-  * 
+  *
   * \brief Template functor to compute the reciprocal of a scalar
   *
   * \sa class CwiseUnaryOp, MatrixBase::cwiseInverse