std::abs(std::valarray) - cppreference.com (original) (raw)
| | | | | --------------------------------------------------------------- | | | | template< class T >valarray<T> abs( const valarray<T>& va ); | | |
Computes absolute value of each element in the value array.
Contents
[edit] Parameters
| va | - | value array to apply the operation to |
|---|
[edit] Return value
Value array containing absolute values of the values in va.
[edit] Notes
Unqualified function (abs) is used to perform the computation. If such function is not available, std::abs is used due to argument-dependent lookup.
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 of std::valarray are provided.
- std::valarray, std::slice_array, std::gslice_array, std::mask_array and std::indirect_array can be constructed from the replacement type.
- For every function taking a const std::valarray<T>& except begin() and end()(since C++11), identical functions taking the replacement types shall be added;
- For every function taking two const std::valarray<T>& arguments, identical functions taking every combination of const std::valarray<T>& and replacement types shall be added.
- The return type does not add more than two levels of template nesting over the most deeply-nested argument type.
[edit] Possible implementation
template valarray abs(const valarray& va) { valarray other = va; for (T& i : other) i = abs(i); return other; // proxy object may be returned }