Fixing FD_Solver test and copy

openfpm_numerics @ b7bc12d2

-Subproject commit 5f4f0c73ceefd23c98b5a0cf78257d6a2f10fe76
+Subproject commit b7bc12d2899352e30c575afdbf73ecf256ad3e11

src/Grid/staggered_dist_grid.hpp

@@ -236,6 +236,11 @@ public:
 			// destination point
 			auto key_dst = g_dst_it.get();
 
+			if (key_dst.getKey().get(0) == 240 && key_dst.getKey().get(1) == 1)
+            {
+                std::cout << "DEBUG " << std::endl;
+            }
+
 			// Transform this id into an id for the Eigen vector
 
 			interp_ele<vid,Grid_dst,typename std::remove_reference<decltype(*this)>::type,sizeof...(pos)> cp(key_dst,g_dst,*this,key_src,interp_pos);

src/Grid/staggered_dist_grid_copy.hpp

@@ -31,6 +31,8 @@ struct interp_ele_sca_array
 
 				grid_dst.template get<Tdst_ele::value>(key_dst) += x.template get<Tsrc::value>(key_m);
 
+				std::cout << "DEBUG: " << x.template get<Tsrc::value>(key_m) << std::endl;
+
 				division += 1.0;
 		}
 		grid_dst.template get<Tdst_ele::value>(key_dst) /= division;