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diff --git a/src/Moof/cml/matrix/matrix_transpose.h b/src/Moof/cml/matrix/matrix_transpose.h
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+/* -*- C++ -*- ------------------------------------------------------------
+ 
+Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
+
+The Configurable Math Library (CML) is distributed under the terms of the
+Boost Software License, v1.0 (see cml/LICENSE for details).
+
+ *-----------------------------------------------------------------------*/
+/** @file
+ *  @brief
+ *
+ *  @todo Currently, the transpose() and T() functions copy the transposed
+ *  result into a temporary, and return it to avoid aliasing problems, e.g.
+ *  C = transpose(C).  By checking for C on the right-hand side, this can
+ *  be avoided, but experimentation is needed to determine the impact on
+ *  performance.  Another option is to use a function to explicitly specify
+ *  when a temporary is needed; e.g. C = transpose(temp(C)).
+ */
+
+#ifndef matrix_transpose_h
+#define matrix_transpose_h
+
+#include <cml/matrix/matrix_expr.h>
+
+#define MATRIX_TRANSPOSE_RETURNS_TEMP
+
+namespace cml {
+namespace et {
+
+/** "Transpose" the given matrix expression.
+ *
+ * This does nothing more than change the result type of the expression
+ * into one with the opposite orientation (i.e. row->col, col->row).
+ */
+template<class ExprT>
+class MatrixTransposeOp
+{
+  public:
+
+    typedef MatrixTransposeOp<ExprT> expr_type;
+
+    /* Record ary-ness of the expression: */
+    typedef unary_expression expr_ary;
+
+    /* Copy the expression by value into higher-up expressions: */
+    typedef expr_type expr_const_reference;
+
+    typedef typename ExprT::value_type value_type;
+    typedef matrix_result_tag result_tag;
+    typedef typename ExprT::size_tag size_tag;
+
+    /* Store the expression traits: */
+    typedef ExprTraits<ExprT> expr_traits;
+
+    /* Get the reference type: */
+    typedef typename expr_traits::const_reference expr_reference;
+
+    /* Swap the orientation: */
+    typedef typename expr_traits::result_type::transposed_type result_type;
+
+    /* Get the temporary type: */
+    typedef typename result_type::temporary_type temporary_type;
+
+    /* For matching by assignability: */
+    typedef cml::et::not_assignable_tag assignable_tag;
+
+
+  public:
+
+    /** Record result size as an enum. */
+    enum {
+        array_rows = result_type::array_rows,
+        array_cols = result_type::array_cols
+    };
+
+
+  public:
+
+    /** Return the expression size as a pair. */
+    matrix_size size() const {
+        return matrix_size(this->rows(),this->cols());
+    }
+
+    /** Return result rows.
+     *
+     * The tranpose has the same number of rows as the original has
+     * columns.
+     */
+    size_t rows() const {
+        return expr_traits().cols(m_expr);
+    }
+
+    /** Return result cols.
+     *
+     * The tranpose has the same number of columns as the original has
+     * rows.
+     */
+    size_t cols() const {
+        return expr_traits().rows(m_expr);
+    }
+
+    /** Return reference to contained expression. */
+    expr_reference expression() const { return m_expr; }
+
+    /** Compute value at index i of the result matrix.
+     *
+     * Element (i,j) of the transpose is element (j,i) of the original
+     * expression.
+     */
+    value_type operator()(size_t i, size_t j) const {
+        return expr_traits().get(m_expr,j,i);
+    }
+
+
+  public:
+
+    /** Construct from the subexpression to store. */
+    explicit MatrixTransposeOp(const ExprT& expr) : m_expr(expr) {}
+
+    /** Copy constructor. */
+    MatrixTransposeOp(const expr_type& e) : m_expr(e.m_expr) {}
+
+
+  protected:
+
+    expr_reference m_expr;
+
+
+  private:
+
+    /* Cannot be assigned to: */
+    expr_type& operator=(const expr_type&);
+};
+
+/** Expression traits class for VectorTransposeOp<>. */
+template<class ExprT>
+struct ExprTraits< MatrixTransposeOp<ExprT> >
+{
+    typedef MatrixTransposeOp<ExprT> expr_type;
+    typedef typename expr_type::value_type value_type;
+    typedef typename expr_type::expr_const_reference const_reference;
+    typedef typename expr_type::result_tag result_tag;
+    typedef typename expr_type::size_tag size_tag;
+    typedef typename expr_type::result_type result_type;
+    typedef typename expr_type::assignable_tag assignable_tag;
+    typedef expr_node_tag node_tag;
+
+    value_type get(const expr_type& m, size_t i, size_t j) const {
+        return m(i,j);
+    }
+
+    matrix_size size(const expr_type& e) const { return e.size(); }
+    size_t rows(const expr_type& e) const { return e.rows(); }
+    size_t cols(const expr_type& e) const { return e.cols(); }
+};
+
+} // namespace et
+
+
+/* Define the transpose operators in the cml namespace: */
+#if defined(MATRIX_TRANSPOSE_RETURNS_TEMP)
+
+/** Matrix transpose operator taking a matrix operand. */
+template<typename E, class AT, typename BO, typename L>
+typename et::MatrixTransposeOp<
+    matrix<E,AT,BO,L>
+>::temporary_type
+transpose(const matrix<E,AT,BO,L>& expr)
+{
+    /* Record the matrix type: */
+    typedef matrix<E,AT,BO,L> matrix_type;
+
+    /* Record the type of the transpose op: */
+    typedef et::MatrixTransposeOp<matrix_type> Op;
+
+    /* Determine the returned matrix type: */
+    typedef typename et::MatrixTransposeOp<
+        matrix_type
+    >::temporary_type tmp_type;
+
+    /* The expression to use to assign the temporary: */
+    typedef et::MatrixXpr<Op> ExprT;
+
+    /* Create the temporary and return it: */
+    tmp_type tmp;
+    cml::et::detail::Resize(tmp,expr.rows(),expr.cols());
+    tmp = ExprT(Op(expr));
+    return tmp;
+}
+
+/** Matrix transpose operator taking an et::MatrixXpr operand.
+ *
+ * The parse tree is automatically compressed by hoisting the MatrixXpr's
+ * subexpression into the subexpression of the MatrixTransposeOp.
+ */
+template<class XprT>
+typename et::MatrixTransposeOp<
+    XprT
+>::temporary_type
+transpose(MATXPR_ARG_TYPE expr)
+{
+    /* Record the type of the transpose op: */
+    typedef et::MatrixTransposeOp<XprT> Op;
+
+    /* Determine the returned matrix type: */
+    typedef typename et::MatrixTransposeOp<XprT>::temporary_type tmp_type;
+
+    /* The expression to use to assign the temporary: */
+    typedef et::MatrixXpr<Op> ExprT;
+
+    /* Create the temporary and return it: */
+    tmp_type tmp;
+    cml::et::detail::Resize(tmp,expr.rows(),expr.cols());
+    tmp = ExprT(Op(expr.expression()));
+    return tmp;
+}
+
+
+/* For notational convenience: */
+
+/** Matrix transpose operator taking a matrix operand. */
+template<typename E, class AT, typename BO, typename L>
+typename et::MatrixTransposeOp<
+    matrix<E,AT,BO,L>
+>::temporary_type
+T(const matrix<E,AT,BO,L>& expr)
+{
+    return transpose(expr);
+}
+
+/** Matrix transpose operator taking an et::MatrixXpr operand.
+ *
+ * The parse tree is automatically compressed by hoisting the MatrixXpr's
+ * subexpression into the subexpression of the MatrixTransposeOp.
+ */
+template<class XprT>
+typename et::MatrixTransposeOp<
+    XprT
+>::temporary_type
+T(MATXPR_ARG_TYPE expr)
+{
+    return transpose(expr);
+}
+
+#else
+
+/* XXX For this to work correctly, matrix assignment and copy have to be
+ * changed to either use a temporary all the time, or to create a temporary
+ * when the same matrix appears on both sides of an assignment, and a
+ * temporary was not already created on the RHS by the ET code.
+ */
+
+/** Matrix transpose operator taking a matrix operand. */
+template<typename E, class AT, typename BO, typename L>
+et::MatrixXpr< et::MatrixTransposeOp< matrix<E,AT,BO,L> > >
+transpose(const matrix<E,AT,BO,L>& expr)
+{
+    typedef et::MatrixTransposeOp< matrix<E,AT,BO,L> > ExprT;
+    return et::MatrixXpr<ExprT>(ExprT(expr));
+}
+
+/** Matrix transpose operator taking an et::MatrixXpr operand.
+ *
+ * The parse tree is automatically compressed by hoisting the MatrixXpr's
+ * subexpression into the subexpression of the MatrixTransposeOp.
+ */
+template<class XprT>
+et::MatrixXpr< et::MatrixTransposeOp<XprT> >
+transpose(MATXPR_ARG_TYPE expr)
+{
+    typedef et::MatrixTransposeOp<XprT> ExprT;
+    return et::MatrixXpr<ExprT>(ExprT(expr.expression()));
+}
+
+
+/* For notational convenience: */
+
+/** Matrix transpose operator taking a matrix operand. */
+template<typename E, class AT, typename BO, typename L>
+et::MatrixXpr< et::MatrixTransposeOp< matrix<E,AT,BO,L> > >
+T(const matrix<E,AT,BO,L>& expr)
+{
+    return transpose(expr);
+}
+
+/** Matrix transpose operator taking an et::MatrixXpr operand.
+ *
+ * The parse tree is automatically compressed by hoisting the MatrixXpr's
+ * subexpression into the subexpression of the MatrixTransposeOp.
+ */
+template<class XprT>
+et::MatrixXpr< et::MatrixTransposeOp<XprT> >
+T(MATXPR_ARG_TYPE expr)
+{
+    return transpose(expr);
+}
+
+#endif
+
+} // namespace cml
+
+#endif
+
+// -------------------------------------------------------------------------
+// vim:ft=cpp