NDArray
=======

.. cpp:class:: numpy::NDArray

   Core array class in the numpy namespace.

Example
-------

.. code-block:: cpp

   #include <numpy/np_ndarray.h>
   using namespace numpy;

   // Create NDArray
   NDArray<double> arr = np::zeros<double>({3, 4});
   NDArray<int> ones = np::ones<int>({2, 2});

   // Access data
   auto shape = arr.shape();
   double val = arr(0, 1);

   // Operations
   auto result = arr + 1.0;
   auto mean_val = np::mean(arr);

Constructors
------------

.. list-table::
   :widths: 55 25 20
   :header-rows: 1

   * - Signature
     - Location
     - Example
   * - ``NDArray(const std::vector<size_t>&shape, const T &fill_value = T{})``
     - NP_NDARRAY.H:50
     - :ref:`View <example-ndarray-ndarray-0>`
   * - ``NDArray(T \*external_data, const std::vector<size_t>&shape, std::shared_ptr<void>owner = nullptr)``
     - NP_NDARRAY.H:54
     - :ref:`View <example-ndarray-ndarray-1>`
   * - ``NDArray(T \*data_ptr, size_toffset, const std::vector<size_t>&shape, const std::vector<ssize_t>&strides, std::shared_ptr<void>owner)``
     - NP_NDARRAY.H:58
     - :ref:`View <example-ndarray-ndarray-2>`

Indexing / Selection
--------------------

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``DType getDType()``
     - DType
     - NP_NDARRAY.H:115
     - :ref:`View <example-ndarray-getdtype-3>`
   * - ``T getElementAt(const std::vector<size_t>&indices)``
     - T
     - NP_NDARRAY.H:72
     - :ref:`View <example-ndarray-getelementat-4>`
   * - ``size_t getOffset()``
     - size_t
     - NP_NDARRAY.H:113
     - 
   * - ``const std::vector<size_t>& getShape()``
     - const std::vector<size_t>&
     - NP_NDARRAY.H:110
     - :ref:`View <example-ndarray-getshape-5>`
   * - ``size_t getSize()``
     - size_t
     - NP_NDARRAY.H:112
     - :ref:`View <example-ndarray-getsize-6>`
   * - ``const std::vector<ssize_t>& getStrides()``
     - const std::vector<ssize_t>&
     - NP_NDARRAY.H:111
     - :ref:`View <example-ndarray-getstrides-7>`
   * - ``std::string getTypeName()``
     - std::string
     - NP_NDARRAY.H:116
     - :ref:`View <example-ndarray-gettypename-8>`
   * - ``T item()``
     - T
     - NP_NDARRAY.H:203
     - :ref:`View <example-ndarray-item-9>`
   * - ``T item(size_tflat_index)``
     - T
     - NP_NDARRAY.H:211
     - :ref:`View <example-ndarray-item-10>`
   * - ``void itemset(const T &value)``
     - void
     - NP_NDARRAY.H:219
     - :ref:`View <example-ndarray-itemset-11>`
   * - ``void itemset(size_tflat_index, const T &value)``
     - void
     - NP_NDARRAY.H:227
     - :ref:`View <example-ndarray-itemset-12>`
   * - ``std::vector<NDArray<size_t>> nonzero()``
     - std::vector<NDArray<size_t>>
     - NP_NDARRAY.H:174
     - :ref:`View <example-ndarray-nonzero-13>`

Statistics
----------

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``T maxArray()``
     - T
     - NP_NDARRAY.H:100
     - :ref:`View <example-ndarray-maxarray-14>`
   * - ``double meanArray()``
     - double
     - NP_NDARRAY.H:98
     - :ref:`View <example-ndarray-meanarray-15>`
   * - ``T minArray()``
     - T
     - NP_NDARRAY.H:99
     - :ref:`View <example-ndarray-minarray-16>`
   * - ``T sumArray()``
     - T
     - NP_NDARRAY.H:97
     - :ref:`View <example-ndarray-sumarray-17>`

Sorting
-------

.. list-table::
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   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``void sort(std::optional<int>axis = std::nullopt, SortKindkind = static_cast<SortKind>(0), boolstable = false)``
     - void
     - NP_NDARRAY.H:106
     - :ref:`View <example-ndarray-sort-18>`

I/O
---

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``std::string tolist()``
     - std::string
     - NP_NDARRAY.H:188
     - :ref:`View <example-ndarray-tolist-19>`

Other Methods
-------------

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``T \* data()``
     - T \*
     - NP_NDARRAY.H:121
     - :ref:`View <example-ndarray-data-20>`
   * - ``const T \* data()``
     - const T \*
     - NP_NDARRAY.H:130
     - :ref:`View <example-ndarray-data-21>`
   * - ``void dump(const std::string &filename)``
     - void
     - NP_NDARRAY.H:289
     - :ref:`View <example-ndarray-dump-22>`
   * - ``void fill(const T &value)``
     - void
     - NP_NDARRAY.H:195
     - :ref:`View <example-ndarray-fill-23>`
   * - ``T & flat(size_tflat_index)``
     - T &
     - NP_NDARRAY.H:235
     - :ref:`View <example-ndarray-flat-24>`
   * - ``const T & flat(size_tflat_index)``
     - const T &
     - NP_NDARRAY.H:243
     - :ref:`View <example-ndarray-flat-25>`
   * - ``bool isAligned()``
     - bool
     - NP_NDARRAY.H:337
     - :ref:`View <example-ndarray-isaligned-26>`
   * - ``bool isCContiguous()``
     - bool
     - NP_NDARRAY.H:152
     - :ref:`View <example-ndarray-isccontiguous-27>`
   * - ``bool isContiguous()``
     - bool
     - NP_NDARRAY.H:151
     - :ref:`View <example-ndarray-iscontiguous-28>`
   * - ``bool isFContiguous()``
     - bool
     - NP_NDARRAY.H:153
     - :ref:`View <example-ndarray-isfcontiguous-29>`
   * - ``bool isWriteable()``
     - bool
     - NP_NDARRAY.H:331
     - :ref:`View <example-ndarray-iswriteable-30>`
   * - ``bool ownsData()``
     - bool
     - NP_NDARRAY.H:114
     - :ref:`View <example-ndarray-ownsdata-31>`
   * - ``void printArray(const std::string &title = "")``
     - void
     - NP_NDARRAY.H:103
     - :ref:`View <example-ndarray-printarray-32>`
   * - ``void setElementAt(const std::vector<size_t>&indices, const T &value)``
     - void
     - NP_NDARRAY.H:73
     - :ref:`View <example-ndarray-setelementat-33>`
   * - ``void setElementAt(std::initializer_list<size_t>indices, const T &value)``
     - void
     - NP_NDARRAY.H:74
     - :ref:`View <example-ndarray-setelementat-34>`
   * - ``void setflags(boolwrite = true, boolalign = false, booluic = false)``
     - void
     - NP_NDARRAY.H:325
     - :ref:`View <example-ndarray-setflags-35>`
   * - ``std::string toString(const std::string &title = "")``
     - std::string
     - NP_NDARRAY.H:102
     - :ref:`View <example-ndarray-tostring-36>`
   * - ``T \* unsafe_data()``
     - T \*
     - NP_NDARRAY.H:142
     - 
   * - ``const T \* unsafe_data()``
     - const T \*
     - NP_NDARRAY.H:146
     - 


Code Examples
-------------

The following examples are extracted from the test suite.

.. _example-ndarray-ndarray-0:

.. dropdown:: NDArray (np_test_1_all.cpp:890)
   :class-title: example-dropdown

   .. code-block:: cpp
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          }
          // std::cout << "[OK] array == scalar";
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testLogicalOperations() {
          std::cout << "========= testLogicalOperations =======================";
      
          // Create boolean arrays
          auto a = NDArray<bool>({3});
          a.setElementAt({0}, true);
          a.setElementAt({1}, false);
          a.setElementAt({2}, true);
      
          auto b = NDArray<bool>({3});
          b.setElementAt({0}, false);
          b.setElementAt({1}, false);
          b.setElementAt({2}, true);
      
          // Test logical_and

.. _example-ndarray-ndarray-1:

.. dropdown:: NDArray (np_test_1_all.cpp:890)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 880
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          }
          // std::cout << "[OK] array == scalar";
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testLogicalOperations() {
          std::cout << "========= testLogicalOperations =======================";
      
          // Create boolean arrays
          auto a = NDArray<bool>({3});
          a.setElementAt({0}, true);
          a.setElementAt({1}, false);
          a.setElementAt({2}, true);
      
          auto b = NDArray<bool>({3});
          b.setElementAt({0}, false);
          b.setElementAt({1}, false);
          b.setElementAt({2}, true);
      
          // Test logical_and

.. _example-ndarray-ndarray-2:

.. dropdown:: NDArray (np_test_1_all.cpp:890)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 880
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          }
          // std::cout << "[OK] array == scalar";
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testLogicalOperations() {
          std::cout << "========= testLogicalOperations =======================";
      
          // Create boolean arrays
          auto a = NDArray<bool>({3});
          a.setElementAt({0}, true);
          a.setElementAt({1}, false);
          a.setElementAt({2}, true);
      
          auto b = NDArray<bool>({3});
          b.setElementAt({0}, false);
          b.setElementAt({1}, false);
          b.setElementAt({2}, true);
      
          // Test logical_and

.. _example-ndarray-getdtype-3:

.. dropdown:: getDType (np_test_1_all.cpp:7238)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
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      :emphasize-lines: 11

                    // << ", size: " << TypeTraits<longdouble>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  clongdouble: " << TypeTraits<clongdouble>::getTypeName()
                    // << ", size: " << TypeTraits<clongdouble>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  intp: " << TypeTraits<intp>::getTypeName()
                    // << ", size: " << TypeTraits<intp>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  uintp: " << TypeTraits<uintp>::getTypeName()
                    // << ", size: " << TypeTraits<uintp>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  bytes: " << TypeTraits<bytes_>::getTypeName()
                    // << ", size: " << TypeTraits<bytes_>::getTypeSize() << " bytes" << std::endl;
      
          // Test getDType()
          // std::cout << "DType Enums:" << std::endl;
          // std::cout << "  longdouble DType: " << static_cast<int>(TypeTraits<longdouble>::getDType()) << std::endl;
          // std::cout << "  clongdouble DType: " << static_cast<int>(TypeTraits<clongdouble>::getDType()) << std::endl;
          // std::cout << "  intp DType: " << static_cast<int>(TypeTraits<intp>::getDType()) << std::endl;
          // std::cout << "  uintp DType: " << static_cast<int>(TypeTraits<uintp>::getDType()) << std::endl;
          // std::cout << "  bytes DType: " << static_cast<int>(TypeTraits<bytes_>::getDType()) << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      

.. _example-ndarray-getelementat-4:

.. dropdown:: getElementAt (np_test_1_all.cpp:49)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 39
      :emphasize-lines: 11

      using namespace numpy::benchmark;
      using namespace numpy::char_;
      
      // Helper functions for array comparison tests
      namespace {
          const double TOLERANCE = 1e-10;
      
          bool allTrue(const NDArray<bool>& arr) {
              std::vector<size_t> indices(arr.getShape().size(), 0);
              do {
                  if (!arr.getElementAt(indices)) {
                      return false;
                  }
              } while (incrementIndices(indices, arr.getShape()));
              return true;
          }
      
          bool allFalse(const NDArray<bool>& arr) {
              std::vector<size_t> indices(arr.getShape().size(), 0);
              do {
                  if (arr.getElementAt(indices)) {

.. _example-ndarray-getshape-5:

.. dropdown:: getShape (np_test_1_all.cpp:47)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 37
      :emphasize-lines: 11

      
      using namespace numpy;
      using namespace numpy::benchmark;
      using namespace numpy::char_;
      
      // Helper functions for array comparison tests
      namespace {
          const double TOLERANCE = 1e-10;
      
          bool allTrue(const NDArray<bool>& arr) {
              std::vector<size_t> indices(arr.getShape().size(), 0);
              do {
                  if (!arr.getElementAt(indices)) {
                      return false;
                  }
              } while (incrementIndices(indices, arr.getShape()));
              return true;
          }
      
          bool allFalse(const NDArray<bool>& arr) {
              std::vector<size_t> indices(arr.getShape().size(), 0);

.. _example-ndarray-getsize-6:

.. dropdown:: getSize (np_test_1_all.cpp:2172)
   :class-title: example-dropdown

   .. code-block:: cpp
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          }
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testArrayEdgeCases() {
          std::cout << "========= testArrayEdgeCases =======================";
      
          // Test 1: Empty arrays
          NDArray<object_> empty_array = createObjectZeros({0});
          if (!(empty_array.getSize() == 0)) {
              std::string description = std::string("testArrayEdgeCases():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(empty_array.getSize() == 0)";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
          if (!(empty_array.getShape() == std::vector<size_t>{0})) {
              std::string description = std::string("testArrayEdgeCases():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(empty_array.getShape() == std::vector<size_t>{0})";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
      

.. _example-ndarray-getstrides-7:

.. dropdown:: getStrides (np_test_1_all.cpp:13373)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
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      :emphasize-lines: 11

      namespace numpy_tests {
      
        using namespace numpy;
      
      
        void testBasicStrides() {
          std::cout << "========= testBasicStrides =======================";
      
          // Test 1D array
          auto array1d = createInt32Array({ 5 }, 10);
          const auto& strides1d = array1d.getStrides();
      
          // std::cout << "1D array shape: (" << array1d.getShape()[0] << ")" << std::endl;
          // std::cout << "1D array strides: (" << strides1d[0] << ")" << std::endl;
      
          if (!(strides1d.size() == 1)) {
              std::string description = std::string("testBasicStrides():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(strides1d.size() == 1)";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
          if (!(strides1d[0] == 1)) {

.. _example-ndarray-gettypename-8:

.. dropdown:: getTypeName (np_test_1_all.cpp:7227)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 7217
      :emphasize-lines: 11

          // std::cout << "Min: " << ip_array.minArray() << std::endl;
          // std::cout << "Max: " << ip_array.maxArray() << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testTypeTraitsExtendedTypes() {
          std::cout << "========= testTypeTraitsExtendedTypes =======================";
      
          // std::cout << "Type Information:" << std::endl;
          // std::cout << "  longdouble: " << TypeTraits<longdouble>::getTypeName()
                    // << ", size: " << TypeTraits<longdouble>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  clongdouble: " << TypeTraits<clongdouble>::getTypeName()
                    // << ", size: " << TypeTraits<clongdouble>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  intp: " << TypeTraits<intp>::getTypeName()
                    // << ", size: " << TypeTraits<intp>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  uintp: " << TypeTraits<uintp>::getTypeName()
                    // << ", size: " << TypeTraits<uintp>::getTypeSize() << " bytes" << std::endl;
          // std::cout << "  bytes: " << TypeTraits<bytes_>::getTypeName()
                    // << ", size: " << TypeTraits<bytes_>::getTypeSize() << " bytes" << std::endl;
      

.. _example-ndarray-item-9:

.. dropdown:: item (np_test_4_all.cpp:20048)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
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      :emphasize-lines: 11

       
      /**
       * @file np_test_phase6.cpp
       * @brief Test suite for Phase 6A - HIGH PRIORITY NDArray methods and masked array utilities
       *
       * Tests:
       * - ndarray.nonzero() - Return indices of non-zero elements
       * - ndarray.tobytes() - Convert to bytes representation
       * - ndarray.tolist() - Convert to nested list string
       * - ndarray.fill() - Fill with scalar value (in-place)
       * - ndarray.item() - Get single element as scalar
       * - ndarray.itemset() - Set single element value
       * - ma.masked_all_like() - Create masked array with all elements masked
       *
       * Created: 2025-10-28
       * Status: Phase 6A Implementation - HIGH PRIORITY functions
       */
      
      #include "../numpy/np_ndarray.h"
      #include "../numpy/np_masked_array.h"
      #include <iostream>

.. _example-ndarray-item-10:

.. dropdown:: item (np_test_4_all.cpp:20048)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 20038
      :emphasize-lines: 11

       
      /**
       * @file np_test_phase6.cpp
       * @brief Test suite for Phase 6A - HIGH PRIORITY NDArray methods and masked array utilities
       *
       * Tests:
       * - ndarray.nonzero() - Return indices of non-zero elements
       * - ndarray.tobytes() - Convert to bytes representation
       * - ndarray.tolist() - Convert to nested list string
       * - ndarray.fill() - Fill with scalar value (in-place)
       * - ndarray.item() - Get single element as scalar
       * - ndarray.itemset() - Set single element value
       * - ma.masked_all_like() - Create masked array with all elements masked
       *
       * Created: 2025-10-28
       * Status: Phase 6A Implementation - HIGH PRIORITY functions
       */
      
      #include "../numpy/np_ndarray.h"
      #include "../numpy/np_masked_array.h"
      #include <iostream>

.. _example-ndarray-itemset-11:

.. dropdown:: itemset (np_test_4_all.cpp:20049)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 20039
      :emphasize-lines: 11

      /**
       * @file np_test_phase6.cpp
       * @brief Test suite for Phase 6A - HIGH PRIORITY NDArray methods and masked array utilities
       *
       * Tests:
       * - ndarray.nonzero() - Return indices of non-zero elements
       * - ndarray.tobytes() - Convert to bytes representation
       * - ndarray.tolist() - Convert to nested list string
       * - ndarray.fill() - Fill with scalar value (in-place)
       * - ndarray.item() - Get single element as scalar
       * - ndarray.itemset() - Set single element value
       * - ma.masked_all_like() - Create masked array with all elements masked
       *
       * Created: 2025-10-28
       * Status: Phase 6A Implementation - HIGH PRIORITY functions
       */
      
      #include "../numpy/np_ndarray.h"
      #include "../numpy/np_masked_array.h"
      #include <iostream>
      #include <cassert>

.. _example-ndarray-itemset-12:

.. dropdown:: itemset (np_test_4_all.cpp:20049)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 20039
      :emphasize-lines: 11

      /**
       * @file np_test_phase6.cpp
       * @brief Test suite for Phase 6A - HIGH PRIORITY NDArray methods and masked array utilities
       *
       * Tests:
       * - ndarray.nonzero() - Return indices of non-zero elements
       * - ndarray.tobytes() - Convert to bytes representation
       * - ndarray.tolist() - Convert to nested list string
       * - ndarray.fill() - Fill with scalar value (in-place)
       * - ndarray.item() - Get single element as scalar
       * - ndarray.itemset() - Set single element value
       * - ma.masked_all_like() - Create masked array with all elements masked
       *
       * Created: 2025-10-28
       * Status: Phase 6A Implementation - HIGH PRIORITY functions
       */
      
      #include "../numpy/np_ndarray.h"
      #include "../numpy/np_masked_array.h"
      #include <iostream>
      #include <cassert>

.. _example-ndarray-nonzero-13:

.. dropdown:: nonzero (np_test_4_all.cpp:18465)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
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            }
      
            std::cout << " -> tests passed\n";
          }
      
          void np_test_phase1_nonzero() {
            std::cout << "========= nonzero: find nonzero indices ====";
      
            // Test 1D array
            auto arr1d = numpy::array({0, 2, 0, 4, 5, 0, 7});
            auto indices1d = numpy::nonzero(arr1d);
      
            // Should return vector with 1 array (for 1D input)
            if (indices1d.size() != 1) {
              std::cout << "  [FAIL] : nonzero 1D returned " << indices1d.size() << " arrays, expected 1\n";
              throw std::runtime_error("nonzero failed: wrong number of arrays for 1D");
            }
      
            // Should find 4 nonzero elements
            if (indices1d[0].getSize() != 4) {
              std::cout << "  [FAIL] : nonzero 1D found " << indices1d[0].getSize() << " elements, expected 4\n";

.. _example-ndarray-maxarray-14:

.. dropdown:: maxArray (np_test_1_all.cpp:234)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 224
      :emphasize-lines: 11

          array.setElementAt({1, 0}, -1.0);
          array.setElementAt({1, 1}, 0.0);
          array.setElementAt({1, 2}, 4.5);
      
          // std::cout << "Test array:" << std::endl;
          //array.printArray();
      
          // std::cout << "Sum: " << array.sumArray() << std::endl;
          // std::cout << "Mean: " << array.meanArray() << std::endl;
          // std::cout << "Min: " << array.minArray() << std::endl;
          // std::cout << "Max: " << array.maxArray() << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testReshapeAndFlatten() {
          std::cout << "========= testReshapeAndFlatten =======================";
      
          auto range_array = NDArray<int32>::createRange(0, 12, 1);
          // std::cout << "Range array (0-11):" << std::endl;
          //range_array.printArray();

.. _example-ndarray-meanarray-15:

.. dropdown:: meanArray (np_test_1_all.cpp:232)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 222
      :emphasize-lines: 11

          array.setElementAt({0, 1}, 2.5);
          array.setElementAt({0, 2}, 3.5);
          array.setElementAt({1, 0}, -1.0);
          array.setElementAt({1, 1}, 0.0);
          array.setElementAt({1, 2}, 4.5);
      
          // std::cout << "Test array:" << std::endl;
          //array.printArray();
      
          // std::cout << "Sum: " << array.sumArray() << std::endl;
          // std::cout << "Mean: " << array.meanArray() << std::endl;
          // std::cout << "Min: " << array.minArray() << std::endl;
          // std::cout << "Max: " << array.maxArray() << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testReshapeAndFlatten() {
          std::cout << "========= testReshapeAndFlatten =======================";
      
          auto range_array = NDArray<int32>::createRange(0, 12, 1);

.. _example-ndarray-minarray-16:

.. dropdown:: minArray (np_test_1_all.cpp:233)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 223
      :emphasize-lines: 11

          array.setElementAt({0, 2}, 3.5);
          array.setElementAt({1, 0}, -1.0);
          array.setElementAt({1, 1}, 0.0);
          array.setElementAt({1, 2}, 4.5);
      
          // std::cout << "Test array:" << std::endl;
          //array.printArray();
      
          // std::cout << "Sum: " << array.sumArray() << std::endl;
          // std::cout << "Mean: " << array.meanArray() << std::endl;
          // std::cout << "Min: " << array.minArray() << std::endl;
          // std::cout << "Max: " << array.maxArray() << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testReshapeAndFlatten() {
          std::cout << "========= testReshapeAndFlatten =======================";
      
          auto range_array = NDArray<int32>::createRange(0, 12, 1);
          // std::cout << "Range array (0-11):" << std::endl;

.. _example-ndarray-sumarray-17:

.. dropdown:: sumArray (np_test_1_all.cpp:231)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 221
      :emphasize-lines: 11

          array.setElementAt({0, 0}, 1.5);
          array.setElementAt({0, 1}, 2.5);
          array.setElementAt({0, 2}, 3.5);
          array.setElementAt({1, 0}, -1.0);
          array.setElementAt({1, 1}, 0.0);
          array.setElementAt({1, 2}, 4.5);
      
          // std::cout << "Test array:" << std::endl;
          //array.printArray();
      
          // std::cout << "Sum: " << array.sumArray() << std::endl;
          // std::cout << "Mean: " << array.meanArray() << std::endl;
          // std::cout << "Min: " << array.minArray() << std::endl;
          // std::cout << "Max: " << array.maxArray() << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testReshapeAndFlatten() {
          std::cout << "========= testReshapeAndFlatten =======================";
      

.. _example-ndarray-sort-18:

.. dropdown:: sort (np_test_1_all.cpp:6258)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 6248
      :emphasize-lines: 11

          std::vector<int> data = gen.generate(100, DataPattern::FEW_UNIQUE);
      
          if (!(data.size() == 100)) {
              std::string description = std::string("test_data_generator_few_uniqueBenchmarkSorting():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(data.size() == 100)";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
      
          // Count unique values
          std::vector<int> sorted_copy = data;
          std::sort(sorted_copy.begin(), sorted_copy.end());
          auto unique_end = std::unique(sorted_copy.begin(), sorted_copy.end());
          size_t unique_count = std::distance(sorted_copy.begin(), unique_end);
      
          // Should have significantly fewer unique values than total elements
          if (!(unique_count < data.size() / 2)) {
              std::string description = std::string("test_data_generator_few_uniqueBenchmarkSorting():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(unique_count < data.size() / 2)";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
      

.. _example-ndarray-tolist-19:

.. dropdown:: tolist (np_test_4_all.cpp:20046)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 20036
      :emphasize-lines: 11

      
      } // namespace numpy_tests
       
      /**
       * @file np_test_phase6.cpp
       * @brief Test suite for Phase 6A - HIGH PRIORITY NDArray methods and masked array utilities
       *
       * Tests:
       * - ndarray.nonzero() - Return indices of non-zero elements
       * - ndarray.tobytes() - Convert to bytes representation
       * - ndarray.tolist() - Convert to nested list string
       * - ndarray.fill() - Fill with scalar value (in-place)
       * - ndarray.item() - Get single element as scalar
       * - ndarray.itemset() - Set single element value
       * - ma.masked_all_like() - Create masked array with all elements masked
       *
       * Created: 2025-10-28
       * Status: Phase 6A Implementation - HIGH PRIORITY functions
       */
      
      #include "../numpy/np_ndarray.h"

.. _example-ndarray-data-20:

.. dropdown:: data (np_test_1_all.cpp:2084)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 2074
      :emphasize-lines: 11

          }
          if (!(derived_ptr->extra == 2)) {
              std::string description = std::string("testObjectHolderEdgeCases():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(derived_ptr->extra == 2)";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
      
          // Test 6: Large object handling
          struct LargeObject {
              std::vector<double> data;
              LargeObject() : data(10000, 3.14159) {}  // Large object
          };
      
          LargeObject large;
          object_ large_obj(large);  // Should handle large objects
          if (!(!large_obj.is_null())) {
              std::string description = std::string("testObjectHolderEdgeCases():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(!large_obj.is_null())";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
          if (!(large_obj.is_type<LargeObject>())) {

.. _example-ndarray-data-21:

.. dropdown:: data (np_test_1_all.cpp:2084)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 2074
      :emphasize-lines: 11

          }
          if (!(derived_ptr->extra == 2)) {
              std::string description = std::string("testObjectHolderEdgeCases():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(derived_ptr->extra == 2)";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
      
          // Test 6: Large object handling
          struct LargeObject {
              std::vector<double> data;
              LargeObject() : data(10000, 3.14159) {}  // Large object
          };
      
          LargeObject large;
          object_ large_obj(large);  // Should handle large objects
          if (!(!large_obj.is_null())) {
              std::string description = std::string("testObjectHolderEdgeCases():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(!large_obj.is_null())";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
          if (!(large_obj.is_type<LargeObject>())) {

.. _example-ndarray-dump-22:

.. dropdown:: dump (np_test_4_all.cpp:22039)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 22029
      :emphasize-lines: 11

              return 1;
          }
      }
      
      } // namespace numpy_tests
       
      // Comprehensive test suite for Phase 6 NDArray Methods
      //
      // This file tests the Phase 6 LOW priority NDArray methods:
      // - byteswap() - Swap byte order for endianness conversion
      // - dump() - Serialize array to binary file
      // - dumps() - Serialize array to byte vector
      // - setflags() - Set array metadata flags
      
      #include <iostream>
      #include <stdexcept>
      #include <fstream>
      #include <cstring>
      #include <vector>
      #include <filesystem>
      #include "../numpy/np_ndarray.h"

.. _example-ndarray-fill-23:

.. dropdown:: fill (np_test_4_all.cpp:20047)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 20037
      :emphasize-lines: 11

      } // namespace numpy_tests
       
      /**
       * @file np_test_phase6.cpp
       * @brief Test suite for Phase 6A - HIGH PRIORITY NDArray methods and masked array utilities
       *
       * Tests:
       * - ndarray.nonzero() - Return indices of non-zero elements
       * - ndarray.tobytes() - Convert to bytes representation
       * - ndarray.tolist() - Convert to nested list string
       * - ndarray.fill() - Fill with scalar value (in-place)
       * - ndarray.item() - Get single element as scalar
       * - ndarray.itemset() - Set single element value
       * - ma.masked_all_like() - Create masked array with all elements masked
       *
       * Created: 2025-10-28
       * Status: Phase 6A Implementation - HIGH PRIORITY functions
       */
      
      #include "../numpy/np_ndarray.h"
      #include "../numpy/np_masked_array.h"

.. _example-ndarray-flat-24:

.. dropdown:: flat (np_test_5_all.cpp:11172)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 11162
      :emphasize-lines: 11

          // ============================================================================
          // NDITER TESTS
          // ============================================================================
      
          void np_test_nditer_basic() {
            std::cout << "========= NDIter: basic C-order iteration =======================";
      
            // Create 2D array
            numpy::NDArray<int> arr({ 3, 4 });
            for (size_t i = 0; i < 12; ++i) {
              arr.flat(i) = static_cast<int>(i);
            }
      
            // Test C-order iteration
            auto it = numpy::nditer(arr, true);
            int count = 0;
            while (!it.is_finished()) {
              int value = *it;
              auto indices = it.indices();
              size_t flat_idx = it.flat_index();
      

.. _example-ndarray-flat-25:

.. dropdown:: flat (np_test_5_all.cpp:11172)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 11162
      :emphasize-lines: 11

          // ============================================================================
          // NDITER TESTS
          // ============================================================================
      
          void np_test_nditer_basic() {
            std::cout << "========= NDIter: basic C-order iteration =======================";
      
            // Create 2D array
            numpy::NDArray<int> arr({ 3, 4 });
            for (size_t i = 0; i < 12; ++i) {
              arr.flat(i) = static_cast<int>(i);
            }
      
            // Test C-order iteration
            auto it = numpy::nditer(arr, true);
            int count = 0;
            while (!it.is_finished()) {
              int value = *it;
              auto indices = it.indices();
              size_t flat_idx = it.flat_index();
      

.. _example-ndarray-isaligned-26:

.. dropdown:: isAligned (np_test_4_all.cpp:22313)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 22303
      :emphasize-lines: 11

              void np_test_phase6_setflags_basic() {
                  std::cout << "========= setflags basic functionality =======================";
      
                  numpy::NDArray<int> arr({5});
      
                  // Check defaults
                  if (!arr.isWriteable()) {
                      std::cout << "  [FAIL] : Default writeable should be true";
                      throw std::runtime_error("default writeable test failed");
                  }
                  if (!arr.isAligned()) {
                      std::cout << "  [FAIL] : Default aligned should be true";
                      throw std::runtime_error("default aligned test failed");
                  }
      
                  // Set writeable to false
                  arr.setflags(false);
                  if (arr.isWriteable()) {
                      std::cout << "  [FAIL] : Writeable should be false";
                      throw std::runtime_error("setflags writeable test failed");
                  }

.. _example-ndarray-isccontiguous-27:

.. dropdown:: isCContiguous (np_test_1_all.cpp:393)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 383
      :emphasize-lines: 11

      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testMemoryLayoutQueries() {
          std::cout << "========= testMemoryLayoutQueries =======================";
      
          auto array = createFloat64Array({2, 3});
      
          // std::cout << "Array contiguous: " << (array.isContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Array C-contiguous: " << (array.isCContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Array F-contiguous: " << (array.isFContiguous() ? "Yes" : "No") << std::endl;
      
          // Test with a transposed view
          auto transposed = array.transposeView();
          // std::cout << "Transposed contiguous: " << (transposed.isContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Transposed C-contiguous: " << (transposed.isCContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Transposed F-contiguous: " << (transposed.isFContiguous() ? "Yes" : "No") << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }

.. _example-ndarray-iscontiguous-28:

.. dropdown:: isContiguous (np_test_1_all.cpp:392)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 382
      :emphasize-lines: 11

          //array.printArray();
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testMemoryLayoutQueries() {
          std::cout << "========= testMemoryLayoutQueries =======================";
      
          auto array = createFloat64Array({2, 3});
      
          // std::cout << "Array contiguous: " << (array.isContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Array C-contiguous: " << (array.isCContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Array F-contiguous: " << (array.isFContiguous() ? "Yes" : "No") << std::endl;
      
          // Test with a transposed view
          auto transposed = array.transposeView();
          // std::cout << "Transposed contiguous: " << (transposed.isContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Transposed C-contiguous: " << (transposed.isCContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Transposed F-contiguous: " << (transposed.isFContiguous() ? "Yes" : "No") << std::endl;
      
          std::cout << " -> tests passed" << std::endl;

.. _example-ndarray-isfcontiguous-29:

.. dropdown:: isFContiguous (np_test_1_all.cpp:394)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 384
      :emphasize-lines: 11

          std::cout << " -> tests passed" << std::endl;
      }
      
      void testMemoryLayoutQueries() {
          std::cout << "========= testMemoryLayoutQueries =======================";
      
          auto array = createFloat64Array({2, 3});
      
          // std::cout << "Array contiguous: " << (array.isContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Array C-contiguous: " << (array.isCContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Array F-contiguous: " << (array.isFContiguous() ? "Yes" : "No") << std::endl;
      
          // Test with a transposed view
          auto transposed = array.transposeView();
          // std::cout << "Transposed contiguous: " << (transposed.isContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Transposed C-contiguous: " << (transposed.isCContiguous() ? "Yes" : "No") << std::endl;
          // std::cout << "Transposed F-contiguous: " << (transposed.isFContiguous() ? "Yes" : "No") << std::endl;
      
          std::cout << " -> tests passed" << std::endl;
      }
      

.. _example-ndarray-iswriteable-30:

.. dropdown:: isWriteable (np_test_4_all.cpp:22309)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 22299
      :emphasize-lines: 11

              // ============================================================================
              // SETFLAGS TESTS
              // ============================================================================
      
              void np_test_phase6_setflags_basic() {
                  std::cout << "========= setflags basic functionality =======================";
      
                  numpy::NDArray<int> arr({5});
      
                  // Check defaults
                  if (!arr.isWriteable()) {
                      std::cout << "  [FAIL] : Default writeable should be true";
                      throw std::runtime_error("default writeable test failed");
                  }
                  if (!arr.isAligned()) {
                      std::cout << "  [FAIL] : Default aligned should be true";
                      throw std::runtime_error("default aligned test failed");
                  }
      
                  // Set writeable to false
                  arr.setflags(false);

.. _example-ndarray-ownsdata-31:

.. dropdown:: ownsData (np_test_1_all.cpp:577)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 567
      :emphasize-lines: 11

          std::cout << "========= testViewMemoryProperties =======================";
      
          auto original = createFloat64Array({3, 4}, 2.5);
      
          // Test various view properties
          auto basic_view = original.view();
          auto transpose_view = original.transposeView();
          auto slice_view = original.sliceView({{0, 2}, {1, 3}});
      
          // Check ownership flags
          bool orig_owns = original.ownsData();
          if (orig_owns != true) {
              std::cout << "[FAIL] in testViewMemoryProperties(): original.ownsData() = " << orig_owns << ", expected true" << std::endl;
              throw std::runtime_error("testViewMemoryProperties(): original ownership flag incorrect");
          }
          bool basic_owns = basic_view.ownsData();
          if (basic_owns != false) {
              std::cout << "[FAIL] in testViewMemoryProperties(): basic_view.ownsData() = " << basic_owns << ", expected false" << std::endl;
              throw std::runtime_error("testViewMemoryProperties(): basic_view ownership flag incorrect");
          }
          bool transpose_owns = transpose_view.ownsData();

.. _example-ndarray-printarray-32:

.. dropdown:: printArray (np_test_1_all.cpp:67)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 57
      :emphasize-lines: 11

              std::vector<size_t> indices(arr.getShape().size(), 0);
              do {
                  if (arr.getElementAt(indices)) {
                      return false;
                  }
              } while (incrementIndices(indices, arr.getShape()));
              return true;
          }
      
          template<typename T>
          void printArray(const NDArray<T>& arr, const std::string& name) {
              std::cout << name << ": ";
              if (arr.getShape().size() == 1) {
                  for (size_t i = 0; i < arr.getShape()[0]; ++i) {
                      // std::cout << arr.getElementAt({i}) << " ";
                  }
              }
              // std::cout << std::endl;
          }
      
          // Helper functions for bitwise operations tests

.. _example-ndarray-setelementat-33:

.. dropdown:: setElementAt (np_test_1_all.cpp:135)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 125
      :emphasize-lines: 11

          //ones_array.printArray();
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testElementAccess() {
          std::cout << "========= testElementAccess =======================";
      
          auto array = createInt32Array({3, 3}, 0);
      
          array.setElementAt({0, 0}, 1);
          array.setElementAt({0, 1}, 2);
          array.setElementAt({0, 2}, 3);
          array.setElementAt({1, 1}, 5);
          array.setElementAt({2, 2}, 9);
      
          // std::cout << "Array after setting elements:" << std::endl;
          //array.printArray();
      
          // std::cout << "Element at (1,1): " << array.getElementAt({1, 1}) << std::endl;
          // std::cout << "Element at (2,2): " << array.getElementAt({2, 2});

.. _example-ndarray-setelementat-34:

.. dropdown:: setElementAt (np_test_1_all.cpp:135)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 125
      :emphasize-lines: 11

          //ones_array.printArray();
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      void testElementAccess() {
          std::cout << "========= testElementAccess =======================";
      
          auto array = createInt32Array({3, 3}, 0);
      
          array.setElementAt({0, 0}, 1);
          array.setElementAt({0, 1}, 2);
          array.setElementAt({0, 2}, 3);
          array.setElementAt({1, 1}, 5);
          array.setElementAt({2, 2}, 9);
      
          // std::cout << "Array after setting elements:" << std::endl;
          //array.printArray();
      
          // std::cout << "Element at (1,1): " << array.getElementAt({1, 1}) << std::endl;
          // std::cout << "Element at (2,2): " << array.getElementAt({2, 2});

.. _example-ndarray-setflags-35:

.. dropdown:: setflags (np_test_4_all.cpp:22041)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 22031
      :emphasize-lines: 11

      }
      
      } // namespace numpy_tests
       
      // Comprehensive test suite for Phase 6 NDArray Methods
      //
      // This file tests the Phase 6 LOW priority NDArray methods:
      // - byteswap() - Swap byte order for endianness conversion
      // - dump() - Serialize array to binary file
      // - dumps() - Serialize array to byte vector
      // - setflags() - Set array metadata flags
      
      #include <iostream>
      #include <stdexcept>
      #include <fstream>
      #include <cstring>
      #include <vector>
      #include <filesystem>
      #include "../numpy/np_ndarray.h"
      
      // IMPORTANT: No using namespace directives to avoid name clashes

.. _example-ndarray-tostring-36:

.. dropdown:: toString (np_test_1_all.cpp:6826)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 6816
      :emphasize-lines: 11

      void testDatetime64CreationDateTime() {
          std::cout << "========= testDatetime64CreationDateTime =======================";
      
          // Test default constructor
          datetime64 default_dt;
          if (!(default_dt.isNaT())) {
              std::string description = std::string("testDatetime64CreationDateTime():") + __FILE__ + ":" + std::to_string(__LINE__) + ": !(default_dt.isNaT())";
              std::cout << std::string("[FAIL] ") + description << std::endl;
              throw std::runtime_error(description);
          }
          // std::cout << "Default datetime64 is NaT: " << default_dt.toString() << std::endl;
      
          // Test value constructor
          datetime64 epoch_day(0, DateTimeUnit::Day);
          // std::cout << "Epoch day: " << epoch_day.toString() << std::endl;
      
          // Test string constructor
          datetime64 date_from_string("2024-01-15");
          // std::cout << "Date from string '2024-01-15': " << date_from_string.toString() << std::endl;
      
          datetime64 datetime_from_string("2024-01-15T10:30:45");