std::atan(std::valarray)
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                    |   Defined in header  <valarray>
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|   template< class T > valarray<T> atan( const valarray<T>& va );  | 
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For each element in va computes arc tangent of the value of the element. 
Parameters
| va | - | value array to apply the operation to | 
Return value
Value array containing arc tangents of the values in va.
Notes
Unqualified function (atan) is used to perform the computation. If such function is not available, std::atan 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.
 - All functions accepting an argument of type const std::valarray& except begin() and end() (since C++11) should also accept the replacement type.
 - All functions accepting two arguments of type const std::valarray& should accept every combination of const 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.
 
Possible implementation
template<class T> valarray<T> atan(const valarray<T>& va) { valarray<T> other = va; for (T &i : other) { i = atan(i); } return other; }  | 
Example
| This section is incomplete Reason: no example  | 
See also
|    applies the function std::asin to each element of valarray   (function template)  | |
|    applies the function std::acos to each element of valarray   (function template)  | |
|    applies the function std::atan2 to a valarray and a value   (function template)  | |
|    applies the function std::tan to each element of valarray   (function template)  | |
|    (C++11)(C++11)  | 
   computes arc tangent (arctan(x))  (function)  | 
|    (C++11)  | 
   computes arc tangent of a complex number (arctan(z))  (function template)  |