Defined in header <valarray> | ||
|---|---|---|
template< class T > class indirect_array; |
std::gslice_array is a helper template used by std::indirect_array subscript operator. It has reference semantics to a subset of the array specified by an indirect array (std::valarray<std::size_t> object).
| Type | Definition |
|---|---|
value_type | T |
constructs a indirect_array (public member function) |
|
destroys a indirect_array (public member function) |
|
| assigns contents (public member function) |
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| performs arithmetic operation on the array referred by indirect array. (public member function) |
#include <iostream>
#include <valarray>
int main()
{
std::valarray<int> data = {0,1,2,3,4,5,6,7,8,9};
std::valarray<std::size_t> idx = {0,2,4,6,8};
std::cout << "Original valarray: ";
for(int n: data) std::cout << n << ' ';
std::cout << '\n';
data[idx] += data[idx]; // double the values at indexes 'idx'
// the type of data[idx] is std::indirect_array<int>
std::cout << "After indirect modification: ";
for(int n: data) std::cout << n << ' ';
std::cout << '\n';
}Output:
Original valarray: 0 1 2 3 4 5 6 7 8 9 After indirect modification: 0 1 4 3 8 5 12 7 16 9
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