std::complex<T>::imag

 

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std::complex

Member functions
complex::complex
complex::operator=
complex::real
complex::imag
complex::operator+=complex::operator-=complex::operator*=complex::operator/=
Non-member functions
operator+operator- operator+operator-operator*operator/ operator==operator!= (until C++20)   operator<<operator>>	real imag abs arg norm conj proj (C++11) polar operator""ioperator""ifoperator""il (C++14)(C++14)(C++14)
Exponential functions
exp
log
log10
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pow
sqrt
Trigonometric functions
sin cos tan	asin (C++11) acos (C++11) atan (C++11)
Hyperbolic functions
sinh cosh tanh	asinh (C++11) acosh (C++11) atanh (C++11)

 

primary template 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)
specialization 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)
specialization 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)
specialization 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

See also

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