operator==,!=(std::complex)

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< cpp‎ | numeric‎ | complex
 
 
 
std::complex
Member functions
Non-member functions
Exponential functions
Power functions
Trigonometric functions
(C++11)
(C++11)
(C++11)
Hyperbolic functions
(C++11)
(C++11)
(C++11)
 
Defined in header <complex>
(1)
template< class T >
bool operator==( const complex<T>& lhs, const complex<T>& rhs );
(until C++14)
template< class T >
constexpr bool operator==( const complex<T>& lhs, const complex<T>& rhs );
(since C++14)
(2)
template< class T >
bool operator==( const complex<T>& lhs, const T& rhs );
(until C++14)
template< class T >
constexpr bool operator==( const complex<T>& lhs, const T& rhs );
(since C++14)
(3)
template< class T >
bool operator==( const T& lhs, const complex<T>& rhs );
(until C++14)
template< class T >
constexpr bool operator==( const T& lhs, const complex<T>& rhs );
(since C++14)
(until C++20)
(4)
template< class T >
bool operator!=( const complex<T>& lhs, const complex<T>& rhs );
(until C++14)
template< class T >
constexpr bool operator!=( const complex<T>& lhs, const complex<T>& rhs );
(since C++14)
(until C++20)
(5)
template< class T >
bool operator!=( const complex<T>& lhs, const T& rhs );
(until C++14)
template< class T >
constexpr bool operator!=( const complex<T>& lhs, const T& rhs );
(since C++14)
(until C++20)
(6)
template< class T >
bool operator!=( const T& lhs, const complex<T>& rhs );
(until C++14)
template< class T >
constexpr bool operator!=( const T& lhs, const complex<T>& rhs );
(since C++14)
(until C++20)

Compares two complex numbers. Scalar arguments are treated as complex numbers with the real part equal to the argument and the imaginary part set to zero.

1-3) Compares lhs and rhs for equality.
4-6) Compares lhs and rhs for inequality.

The != operator is synthesized from operator==.

(since C++20)

Parameters

lhs, rhs - the arguments to compare: either both complex numbers or one complex and one scalar of matching type (float, double, long double)

Return value

1-3) true if respective parts of lhs are equal to rhs, false otherwise.
4-6) !(lhs == rhs)

Example

#include <complex>
 
int main()
{
    using std::operator""i; // or: using namespace std::complex_literals;
 
    static_assert(1.0i == 1.0i);
    static_assert(2.0i != 1.0i);
 
    constexpr std::complex z(1.0, 0.0);
    static_assert(z == 1.0);
    static_assert(1.0 == z);
    static_assert(2.0 != z);
    static_assert(z != 2.0);
}