fix Matrix::Map/MapAligned documentation, and rephrase the tutorial on Map

Eigen/src/Core/Matrix.h

@@ -402,9 +402,10 @@ class Matrix
     void swap(const MatrixBase<OtherDerived>& other);
 
     /** \name Map
-      * These are convenience functions returning Map objects. The Map() static functions return unaligned Map objects,
+      * These are convenience functions returning Map objects.
-      * while the AlignedMap() functions return aligned Map objects and thus should be called only with 16-byte-aligned
+      *
-      * \a data pointers.
+      * \warning Do not use MapAligned in the Eigen 2.0. Mapping aligned arrays will be fully
+      * supported in Eigen 3.0 (already implemented in the development branch)
       *
       * \see class Map
       */

doc/QuickStartGuide.dox

@@ -229,17 +229,24 @@ Of course, fixed-size matrices can't be resized.
 
 
 \subsection TutorialMap Map
-Any memory buffer can be mapped as an Eigen expression:
+Any memory buffer can be mapped as an Eigen expression using the Map() static method:
-<table class="tutorial_code"><tr><td>
 \code
 std::vector<float> stlarray(10);
-Map<VectorXf>(&stlarray[0], stlarray.size()).setOnes();
+VectorXf::Map(&stlarray[0], stlarray.size()).squaredNorm();
-int data[4] = 1, 2, 3, 4;
+\endcode
-Matrix2i mat2x2(data);
+Here VectorXf::Map returns an object of class Map<VectorXf>, which behaves like a VectorXf except that it uses the existing array. You can write to this object, that will write to the existing array. You can also construct a named obtect to reuse it:
-MatrixXi mat2x2 = Map<Matrix2i>(data);
+\code
-MatrixXi mat2x2 = Map<MatrixXi>(data,2,2);
+float array[rows*cols];
+Map<MatrixXf> m(array,rows,cols);
+m = othermatrix1 * othermatrix2;
+m.eigenvalues();
+\endcode
+In the fixed-size case, no need to pass sizes:
+\code
+float array[9];
+Map<Matrix3d> m(array);
+Matrix3d::Map(array).setIdentity();
 \endcode
-</td></tr></table>