start preparing sliced array access

Author: philippwindischhofer

src/DenseNDArray.hh

@@ -157,6 +157,14 @@ public:
     return rhs.m_data == m_data;
   }
 
+  // to assign blocks of data in an efficient way
+  void copy_from(const DenseNDArray<T, dims>& src,
+		 const DenseNDArray<std::size_t, 1>& ind_src_start, const DenseNDArray<std::size_t, 1>& ind_src_stop,
+		 const DenseNDArray<std::size_t, 1>& ind_dest_start, const DenseNDArray<std::size_t, 1>& ind_dest_stop) {
+
+    
+  }
+  
   // template <std::size_t len>
   // bool operator==(const std::array<T, len>& rhs) const requires(dims == 1) {
   //   if(len != m_data.size()) {

src/NDArrayOperations.hh

@@ -165,7 +165,7 @@ namespace NDArrayOps {
 
     return retval;
   }
-
+  
   template<class T, std::size_t dims, template <class, std::size_t> class ArrayT>
   DenseNDArray<T, dims> min(const ArrayT<T, dims>& a, const ArrayT<T, dims>& b) {
 

tests/internals/testArrayOps.cxx

@@ -1,8 +1,9 @@
 #include <iostream>
+#include "DenseNDArray.hh"
 #include "NDArrayOperations.hh"
 
-int main(int argc, char* argv[]) {
-
+int test_concatenation() {
+  
   DenseNDArray<float, 2> darr_1({3, 3}, -1.0);
   DenseNDArray<float, 2> darr_2({6, 3}, 1.0);
 
@@ -19,6 +20,31 @@ int main(int argc, char* argv[]) {
   for(auto& cur : darr_res_1.shape()) {
     std::cout << cur << std::endl;
   }
+
+  return 0;
+}
+
+int test_slicing() {
+
+  DenseNDArray<float, 2> darr_1({30, 30}, -1.0);
+  DenseNDArray<float, 2> darr_2({3, 3}, 1.0);
+
+  darr_1.copy_from(darr_2,
+		   {0, 0}, {2, 2},   // index range in src array
+		   {0, 0}, {2, 2});  // index range in destination array
+
+  std::cout << darr_1(0, 0) << std::endl;
+  std::cout << darr_1(0, 1) << std::endl;
+  std::cout << darr_1(1, 1) << std::endl;
+  
+  return 0;
+}
+
+int main(int argc, char* argv[]) {
+
+  // test_concatenation();
+
+  test_slicing();
 
   std::cout << "done" << std::endl;
 }