std::valarray<T>::shift
valarray<T> shift( int count ) const; |
Returns a new valarray of the same size with elements whose positions are shifted by count
elements. The new position of each element is i−count where i is the previous position. The value of shifted in elements is T()
.
Parameters
count | - | number of positions to shift the elements by |
Return value
The resulting valarray with shifted elements.
Notes
The function can be implemented with the return type different from std::valarray
. In this case, the replacement type has the following properties:
- All
const
member functions ofstd::valarray
are provided. -
std::valarray
,std::slice_array
,std::gslice_array
,std::mask_array
andstd::indirect_array
can be constructed from the replacement type. - All functions accepting an argument of type
const std::valarray&
exceptbegin()
andend()
(since C++11) should also accept the replacement type. - All functions accepting two arguments of type
const std::valarray&
should accept every combination ofconst std::valarray&
and the replacement type. - The return type does not add more than two levels of template nesting over the most deeply-nested argument type.
Example
#include <iostream> #include <valarray> int main() { std::valarray<int> v{1, 2, 3, 4, 5, 6, 7, 8}; for (auto const& val : v) { std::cout << val << " "; } std::cout << "\n"; std::valarray<int> v2 = v.shift(2); for (auto const& val : v2) { std::cout << val << " "; } std::cout << "\n"; }
Output:
1 2 3 4 5 6 7 8 3 4 5 6 7 8 0 0
See also
circular shift of the elements of the valarray (public member function) |
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