std::atan(std::complex)
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                    |   Defined in header <complex>
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|   template< class T >  complex<T> atan( const complex<T>& z );  | 
(since C++11) | |
Computes complex arc tangent of a complex value z. Branch cut exists outside the interval [−i ; +i] along the imaginary axis.
[edit] Parameters
| z | - | complex value | 
[edit] Return value
Complex arc tangent of z in the range [−iπ/2 ; +iπ/2] along the imaginary axis.
[edit] See also
|    (C++11)  | 
   computes arc sine of a complex number (arcsin(z))  (function template)  | 
|    (C++11)  | 
   computes arc cosine of a complex number (arccos(z))   (function template)  |