std::valarray<T>::operator+,-,~,!
| valarray<T> operator+() const; | (1) | |
| valarray<T> operator-() const; | (2) | |
| valarray<T> operator~() const; | (3) | |
| valarray<bool> operator!() const; | (4) | 
Applies unary operators to each element in the numeric array.
Parameters
(none).
Return value
A numeric array containing elements with values obtained by applying corresponding operator to the values in *this.
Exceptions
(none).
Notes
Each of the operators can only be instantiated if the following requirements are met:
-  The indicated operator can be applied to type T
-  The result value can be unambiguously converted to T(1-3) orbool(4).
The function can be implemented with the return type different from std::valarray. In this case, the replacement type has the following properties:
-  All constmember functions ofstd::valarrayare provided.
-  std::valarray,std::slice_array,std::gslice_array,std::mask_arrayandstd::indirect_arraycan 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.
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