std::imag(std::complex)
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                    |   Defined in header  <complex>
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| (1) | ||
template< class T >  T imag( const std::complex<T>& z );  | 
(until C++14) | |
|   template< class T >  constexpr T imag( const std::complex<T>& z );  | 
(since C++14) | |
|   Additional overloads (since C++11)  | 
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|   Defined in header  <complex>
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| (A) | ||
float       imag( float f ); double      imag( double f );  | 
(until C++14) | |
|   constexpr float       imag( float f ); constexpr double      imag( double f );  | 
 (since C++14)  (until C++23)  | 
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|   template< class FloatingPoint > FloatingPoint imag( FloatingPoint f );  | 
(since C++23) | |
| (B) | ||
template< class Integer >  double imag( Integer i );  | 
(until C++14) | |
|   template< class Integer >  constexpr double imag( Integer i );  | 
(since C++14) | |
1) Returns the imaginary part of the complex number z, i.e. z.imag().
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 A,B) Additional overloads are provided for all integer and floating-point types, which are treated as complex numbers with zero imaginary part. 
 | 
(since C++11) | 
Parameters
| z | - | complex value | 
| f | - | floating-point value | 
| i | - | integer value | 
Return value
1) The imaginary part of z.
A) decltype(f){} (zero).
B) 0.0.
Notes
The additional overloads are not required to be provided exactly as (A,B). They only need to be sufficient to ensure that for their argument num:
-  If num has a standard(until C++23) floating-point type 
T, then std::imag(num) has the same effect as std::imag(std::complex<T>(num)). - Otherwise, if num has an integer type, then std::imag(num) has the same effect as std::imag(std::complex<double>(num)).
 
See also
|   accesses the imaginary part of the complex number  (public member function)  | |
|   returns the real part  (function template)  | |
|   C documentation for cimag 
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