valarray

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1. Array Initialization

std::valarray<int> v(10);  // Initialize with 10 zeros

2. Array Arithmetic

std::valarray<int> v1 = {1, 2, 3}, v2 = {4, 5, 6};
std::valarray<int> result = v1 + v2;  // {5, 7, 9}

3. Array Slicing

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> slice = v[std::slice(1, 2, 1)];  // {2}

4. Array Masking

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<bool> mask = v > 2;  // {false, false, true, true, true}
std::valarray<int> masked = v[mask];  // {3, 4, 5}

5. Element-wise Functions

std::valarray<double> v = {1.2, 2.3, 3.4};
std::valarray<double> result = std::sqrt(v);  // {1.095445, 1.516575, 1.843906}

6. Array Accumulation

std::valarray<int> v = {1, 2, 3, 4, 5};
int sum = std::accumulate(v.begin(), v.end(), 0);  // 15

7. Matrix Multiplication

std::valarray<double> a = {1, 2, 3}, b = {4, 5, 6};
std::valarray<double> result = a * b;  // {14, 32, 48}

8. Array Broadcasting

std::valarray<int> v = {1, 2, 3};
std::valarray<int> scalar = 4;
std::valarray<int> result = v + scalar;  // {5, 6, 7}

9. Complex Number Operations

std::valarray<std::complex<double>> v = {std::complex<double>(1, 2), std::complex<double>(3, 4)};
std::valarray<std::complex<double>> result = v * v;  // {5i, 25}

10. Vector Operations

std::valarray<double> v1 = {1, 2, 3}, v2 = {4, 5, 6};
std::valarray<double> result = v1 * v2;  // {4, 10, 18}

11. Array Division

std::valarray<double> v1 = {1, 2, 3}, v2 = {4, 5, 6};
std::valarray<double> result = v1 / v2;  // {0.25, 0.4, 0.5}

12. Array Comparison

std::valarray<int> v1 = {1, 2, 3}, v2 = {4, 5, 6};
std::valarray<int> result = v1 < v2;  // {true, true, true}

13. Array Maximum and Minimum

std::valarray<int> v = {1, 2, 3, 4, 5};
int max = v.max();  // 5
int min = v.min();  // 1

14. Array Rounding

std::valarray<double> v = {1.2345, 2.3456, 3.4567};
std::valarray<double> result = std::round(v);  // {1.0, 2.0, 3.0}

15. Array Sorting

std::valarray<int> v = {3, 1, 4, 2, 5};
std::sort(v.begin(), v.end());  // {1, 2, 3, 4, 5}

16. Array Reversing

std::valarray<int> v = {1, 2, 3, 4, 5};
std::reverse(v.begin(), v.end());  // {5, 4, 3, 2, 1}

17. Array Rotation

std::valarray<int> v = {1, 2, 3, 4, 5};
std::rotate(v.begin(), v.begin() + 1, v.end());  // {2, 3, 4, 5, 1}

18. Array Shuffling

std::valarray<int> v = {1, 2, 3, 4, 5};
std::random_shuffle(v.begin(), v.end());  // Randomly shuffles the array

19. Array Intersection

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::set_intersection(v1.begin(), v1.end(), v2.begin(), v2.end());  // {2, 4}

20. Array Union

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::set_union(v1.begin(), v1.end(), v2.begin(), v2.end());  // {1, 2, 3, 4, 5, 6, 8, 10}

21. Array Difference

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::set_difference(v1.begin(), v1.end(), v2.begin(), v2.end());  // {1, 3, 5}

22. Array Symmetric Difference

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::set_symmetric_difference(v1.begin(), v1.end(), v2.begin(), v2.end());  // {1, 3, 5, 6, 8, 10}

23. Array Copy

std::valarray<int> v1 = {1, 2, 3}, v2 = v1;  // Copies v1 to v2

24. Array Assignment

std::valarray<int> v1 = {1, 2, 3}, v2 = {4, 5, 6};
v1 = v2;  // Assigns v2 to v1

25. Array Concatenation

std::valarray<int> v1 = {1, 2, 3}, v2 = {4, 5, 6};
std::valarray<int> result = std::concatenate(v1, v2);  // {1, 2, 3, 4, 5, 6}

26. Array Reshaping

std::valarray<int> v = {1, 2, 3, 4, 5, 6};
std::valarray<int> result = v.reshape(2, 3);  // Reshapes v into a 2x3 matrix

27. Array Transposing

std::valarray<double> v = {1.1, 2.2, 3.3, 4.4};
std::valarray<double> result = v.transpose();  // Transposes v

28. Array Flattening

std::valarray<int> v = {1, 2, 3, 4, 5, 6};
std::valarray<int> result = v.flatten();  // Flattens v

29. Array Filling

std::valarray<int> v(10);
v.fill(5);  // Fills v with 5s

30. Array Swapping

std::valarray<int> v1 = {1, 2, 3}, v2 = {4, 5, 6};
std::swap(v1, v2);  // Swaps v1 and v2

31. Array Searching

std::valarray<int> v = {1, 2, 3, 4, 5};
int index = v.find(3);  // Returns the index of the first occurrence of 3

32. Array Counting

std::valarray<int> v = {1, 2, 3, 4, 5};
int count = v.count(3);  // Returns the number of occurrences of 3

33. Array Reducing

std::valarray<int> v = {1, 2, 3, 4, 5};
int sum = v.reduce([](int x, int y) { return x + y; });  // Returns the sum of all elements

34. Array Filtering

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> result = v.filter([](int x) { return x > 2; });  // Returns an array of elements greater than 2

35. Array Mapping

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> result = v.map([](int x) { return x * x; });  // Returns an array of squared elements

36. Array Fold Left

std::valarray<int> v = {1, 2, 3, 4, 5};
int result = v.fold_left([](int x, int y) { return x + y; });  // Returns the sum of all elements

37. Array Fold Right

std::valarray<int> v = {1, 2, 3, 4, 5};
int result = v.fold_right([](int x, int y) { return x + y; });  // Returns the sum of all elements

38. Array Generate

std::valarray<int> v = std::generate(10, []() { return rand() % 10; });  // Generates an array of 10 random numbers

39. Array Filter Index

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> result = v.filter_index([](int x, int i) { return x % 2 == 0; });  // Returns an array of indices of even elements

40. Array Unique

std::valarray<int> v = {1, 2, 3, 4, 5, 1, 2, 3};
std::valarray<int> result = v.unique();  // Returns an array of unique elements

41. Array Intersection Indexed

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::intersection_indexed(v1.begin(), v1.end(), v2.begin(), v2.end());  // Returns an array of indices of intersecting elements

42. Array Union Indexed

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::union_indexed(v1.begin(), v1.end(), v2.begin(), v2.end());  // Returns an array of indices of union of elements

43. Array Difference Indexed

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::difference_indexed(v1.begin(), v1.end(), v2.begin(), v2.end());  // Returns an array of indices of difference of elements

44. Array Symmetric Difference Indexed

std::valarray<int> v1 = {1, 2, 3, 4, 5}, v2 = {2, 4, 6, 8, 10};
std::valarray<int> result = std::symmetric_difference_indexed(v1.begin(), v1.end(), v2.begin(), v2.end());  // Returns an array of indices of symmetric difference of elements

45. Array Reverse Indexed

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> result = std::reverse_indexed(v.begin(), v.end());  // Returns an array of reversed indices

46. Array Rotate Indexed

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> result = std::rotate_indexed(v.begin(), v.begin() + 1, v.end());  // Returns an array of rotated indices

47. Array Shuffle Indexed

std::valarray<int> v = {1, 2, 3, 4, 5};
std::valarray<int> result = std::shuffle_indexed(v.begin(), v.end());  // Returns an array of shuffled indices

48. Array Sorted Indexed

std::valarray<int> v = {3, 1, 4, 2, 5};
std::valarray<int> result = std::sorted_indexed(v.begin(), v.end());  // Returns an array of sorted indices

49. Array Stable Sort Indexed

std::valarray<int> v = {3, 1, 4, 2, 5};
std::valarray<int> result = std::stable_sort_indexed(v.begin(), v.end());  // Returns an array of stably sorted indices

50. Array Partial Sort Indexed

std::valarray<int> v = {3, 1, 4, 2, 5};
std::valarray<int> result = std::partial_sort_indexed(v.begin(), v.begin() + 3, v.end());  // Returns an array of partially sorted indices