array: adjust eigen conversions

src/action.hpp

@@ -10,9 +10,11 @@ inline Scalar S_2(Array<Scalar,2> Q)
 {
     Q(0u,0u) = 1;
     Q(0u,1u) = 2;
+    Q(1u,1u) = 3;
     return Scalar(0);
 }
 
 
 
 #endif
+

src/array.hpp

@@ -154,11 +154,13 @@ public:
 
     EigenMap to_matrix() const
         {
-            static_assert(NDim == 2, "matrixes must be two-dimensional");
+            static_assert(NDim == 2, "matrix must be two-dimensional");
             return {(Scalar *)data_.data() + offset_,
-                shape_[0], shape_[1],
-                {(long)stride_[1], (long)stride_[0]}};
+                static_cast<Eigen::Index>(shape_[0]), static_cast<Eigen::Index>(shape_[1]),
+                {static_cast<Eigen::Index>(stride_[1]), static_cast<Eigen::Index>(stride_[0])}};
         }
+
+    operator EigenMap() const { return to_matrix(); }
 };
 
 

src/main.cpp

@@ -33,7 +33,7 @@ int main()
 
     auto mat = Q.to_matrix();
 
-    mat(1,1) = 123;
+    mat = mat * mat;
 
     dump(Q0);
     std::cout << mat << std::endl;