NumC

Summary

• Library for N-D array manipulation in C++.

Example

• Array Creation

  // 1D Array Initialization.
  auto arr1 = ND_ARRAY<nc::float32>({1 ,2 ,3});

  // 2D Array Initialization.
  auto arr2 = ND_ARRAY<nc::float32>({{0, 1, 2}, {3, 4, 5}, {6, 7, 8}});

  // 3D Array Initialization.
  auto arr3 = ND_ARRAY<nc::float32>({{{0, 1, 2}}, {{3, 4, 5}}, {{6, 7, 8}}});

  // Creating 4D Array by defining shape.
  nc::shape_t shape = {5, 3, 3, 2};
  auto arr4 = ND_ARRAY<nc::float32>(shape);

• Array Iteration

  // Iterating throughout the array to get and set values.
  for (auto it = arr.begin(); it != arr.end(); ++it)
  {
      *it *= 10;
      std::cout << *it << std::endl;
  }
  
  // Constant iterator.
  for (auto it = arr.cbegin(); it != arr.cend(); ++it)
      *it *= 10; // Error - cannot assign value to read-only location.

• Array Basic Operations

  auto arr1 = ND_ARRAY<nc::float32>({0, 1, 2, 3, 4});
  auto arr2 = ND_ARRAY<nc::int32>({5, 6, 7, 8, 9});
  auto arr3 = ND_ARRAY<nc::uint16>({10, 11, 12, 13, 14});
  auto arr4 = ND_ARRAY<nc::float64>({100, 100, 100, 100, 100});
  
  auto res1 = (arr1 + arr2 - arr3) * arr3 / arr4;

• Array Broadcasted Operations

  // Shape - (3, 1, 2)
  auto arr1 = ND_ARRAY<nc::float32>({{{1, 2}}, {{3, 4}}, {{5, 6}}});
  
  // Shape - (3, 2)
  auto arr2 = ND_ARRAY<nc::int32>({{1, 2} , {3, 4}, {5, 6}});
  
  // Shape - (2)
  auto arr3 = ND_ARRAY<nc::int32>({10, 20});
  
  auto bd_arr1 = arr3 - (arr1 + arr2);
  
  // Scalar broadcasting.
  auto bd_arr2 = arr2 + (arr1 * 100);

• Array Slicing

  nc::slices_t slices = { nc::indices_t(2, -1), nc::indices_t(0, -1), nc::indices_t(1, -1)};
  auto s1 = nc::Utils::slice(arr, slices);
  
  // Nested slicing
  nc::slices_t slices2 = {nc::indices_t(1, 3), nc::indices_t(1, -1)};
  auto s2 = nc::Utils::slice(s1, slices2);

• Array Reshaping

  nc::shape_t newShape1 = {10, 9};
  auto r1 = nc::Utils::reshape(arr, newShape1);
  
  // Nested reshaping
  nc::shape_t newShape2 = {15, -1, 1, 1};
  auto r2 = nc::Utils::reshape(r1, newShape2);

• Array Transposing

  nc::size_t_v axes = {1, 0, 2, 3};
  auto t1 = nc::Utils::transpose(arr, axes);
  
  // Default transposing.
  auto t2 = nc::Utils::transpose(arr);

• Display Array

  nc::Utils::print_array(arr);

  [OUT]:
      array(
          shape(3, 3),
  
          indices([0, 3), [0, 3)),
  
          strides(3, 1),
  
          [[0.000000, 1.000000, 2.000000],
          [3.000000, 4.000000, 5.000000],
          [6.000000, 7.000000, 8.000000]]
      )