std::imag(std::complex)
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   Defined in header <complex>
   | 
||
|   template< class T >  T imag( const complex<T>& z );  | 
||
Returns the imaginary component of the complex number z, i.e. z.imag().
[edit] Parameters
| z | - | complex value | 
[edit] Return value
the imaginary component of z
[edit] See also
|    accesses the real part of the complex number  (public member function)  | |
|    accesses the imaginary part of the complex number  (public member function)  | |
|     imag  | 
   returns the imaginary component   (function template)  |