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std::complex<T>::imag

std::complex<T>
	(1)
T imag() const;		(until C++14)
constexpr T imag() const;		(since C++14)
	(2)
void imag( T value );		(until C++20)
constexpr void imag( T value );		(since C++20)
std::complex<float>
	(1)
float imag() const;		(until C++11)
constexpr float imag() const;		(since C++11)
	(2)
void imag( float value );		(until C++20)
constexpr void imag( float value );		(since C++20)
std::complex<double>
	(1)
double imag() const;		(until C++11)
constexpr double imag() const;		(since C++11)
	(2)
void imag( double value );		(until C++20)
constexpr void imag( double value );		(since C++20)
std::complex<long double>
	(1)
long double imag() const;		(until C++11)
constexpr long double imag() const;		(since C++11)
	(2)
void imag( long double value );		(until C++20)
constexpr void imag( long double value );		(since C++20)

Accesses the imaginary part of the complex number.

1) Returns the imaginary part.

2) Sets the imaginary part to value.

Parameters

value

the value to set the imaginary part to

Return value

1) The imaginary part of *this.

2) (none)

Notes

In C++11, overload (1) in std::complex specializations used to be specified without const qualifier. However, in C++11, a constexpr specifier used in a non-static member function implies const, and thus the behavior is as if const is specified.

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 387	C++98	the imaginary part could not be set directly	can be set directly via a new `imag` overload

imag	returns the imaginary part (function template)
real	accesses the real part of the complex number (public member function)

std::complex<T>::imag

Parameters

Return value

Notes

Defect reports

See also