add default parameters for InnerStride/OuterStride to be

able to simply write OuterStride<> instead of OuterStride<Dynamic>

Eigen/src/Core/Map.h

@@ -57,7 +57,9 @@
   *
   * Here's an example of mapping an array while specifying an outer stride. Here, since we're mapping
   * as a column-major matrix, 'outer stride' means the pointer increment between two consecutive columns.
-  * Here, we're specifying the outer stride as a runtime parameter.
+  * Here, we're specifying the outer stride as a runtime parameter. Note that here \c OuterStride<> is
+  * a short version of \c OuterStride<Dynamic> because the default template parameter of OuterStride
+  * is  \c Dynamic
   * \include Map_outer_stride.cpp
   * Output: \verbinclude Map_outer_stride.out
   *

Eigen/src/Core/Stride.h

@@ -46,6 +46,7 @@
   *  \param _OuterStrideAtCompileTime the outer stride, or Dynamic if you want to specify it at runtime.
   *  \param _InnerStrideAtCompileTime the inner stride, or Dynamic if you want to specify it at runtime.
   *
+  * Here is an example:
   * \include Map_general_stride.cpp
   * Output: \verbinclude Map_general_stride.out
   *
@@ -90,8 +91,9 @@ class Stride
     ei_variable_if_dynamic<Index, InnerStrideAtCompileTime> m_inner;
 };
 
-/** \brief Convenience specialization of Stride to specify only an inner stride */
-template<int Value>
+/** \brief Convenience specialization of Stride to specify only an inner stride
+  * See class Map for some examples */
+template<int Value = Dynamic>
 class InnerStride : public Stride<0, Value>
 {
     typedef Stride<0, Value> Base;
@@ -101,8 +103,9 @@ class InnerStride : public Stride<0, Value>
     InnerStride(Index v) : Base(0, v) {}
 };
 
-/** \brief Convenience specialization of Stride to specify only an outer stride */
-template<int Value>
+/** \brief Convenience specialization of Stride to specify only an outer stride
+  * See class Map for some examples */
+template<int Value = Dynamic>
 class OuterStride : public Stride<Value, 0>
 {
     typedef Stride<Value, 0> Base;

doc/snippets/Map_outer_stride.cpp

@@ -1,5 +1,3 @@
 int array[12];
 for(int i = 0; i < 12; ++i) array[i] = i;
-cout << Map<MatrixXi, 0, OuterStride<Dynamic> >
-         (array, 3, 3, OuterStride<Dynamic>(4))
-     << endl;
+cout << Map<MatrixXi, 0, OuterStride<> >(array, 3, 3, OuterStride<>(4)) << endl;