# std::complex<T>::real

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< cpp‎ | numeric‎ | complex

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

Accesses the real part of the complex number.

1) Returns the real part.
2) Sets the real part to value.

### Parameters

value | - | the value to set the real part to

### Return value

1) The real 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 real part could not be set directly | can be set directly via a new `real` overload

### See also

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

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