std::imag(std::complex)
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std::complex 
  
 
 
 
 
 
 
(until C++20)  
(C++26)
  (C++26)
(C++26)
Defined in header 
 
 
<complex> 
  
 (1)
 
template< class T > 
T imag( const std::complex <T>& z );
 
 (until C++14)
T imag( const std::complex <T>& z );
template< class T > 
constexpr T imag( const std::complex <T>& z );
 
 (since C++14) 
constexpr T imag( const std::complex <T>& z );
Additional overloads (since C++11)
 
 
Defined in header 
 
 
<complex> 
  
 (A)
 
float       imag( float f );
 
 (until C++14)
double      imag( double f );
constexpr float       imag( float f );
 
 (since C++14) constexpr double      imag( double f );
(until C++23)
template< class FloatingPoint >
FloatingPoint imag( FloatingPoint f );
 
 (since C++23) 
FloatingPoint imag( FloatingPoint f );
 
 (B)
 
template< class Integer > 
double imag( Integer i );
 
 (until C++14)
double imag( Integer i );
template< class Integer > 
constexpr double imag( Integer i );
 
 (since C++14) 
constexpr double imag( Integer i );
1) Returns the imaginary part of the complex number z, i.e. z.imag().
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)Contents
[edit] Parameters
 z
 -
 complex value
 f
 -
 floating-point value
 i
 -
 integer value
[edit] Return value
1) The imaginary part of z.
A) decltype(f){} (zero).
B) 0.0.
[edit] 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)).
[edit] See also
C documentation  for cimag