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

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

Numerics library

Common mathematical functions
Mathematical special functions (C++17)
Mathematical constants (C++20)
Basic linear algebra algorithms (C++26)
Data-parallel types (SIMD) (C++26)
Floating-point environment (C++11)
Complex numbers
Numeric array (valarray)
Pseudo-random number generation
Bit manipulation (C++20)
Saturation arithmetic (C++26)
Factor operations
gcd (C++17)	lcm (C++17)
Interpolations
midpoint (C++20)	lerp (C++20)
Generic numeric operations
iota (C++11) ranges::iota (C++23) accumulate inner_product adjacent_difference    partial_sum	reduce (C++17) transform_reduce (C++17) inclusive_scan (C++17) exclusive_scan (C++17) transform_inclusive_scan (C++17) transform_exclusive_scan (C++17)
C-style checked integer arithmetic
ckd_add (C++26) ckd_sub (C++26)	ckd_mul (C++26)

 

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>> get(std::complex) (C++26)	real imag abs arg norm conj proj (C++11) polar operator""ioperator""ifoperator""il (C++14)(C++14)(C++14)
Exponential functions
log   log10   exp
Power functions
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)
Helper types
tuple_size<std::complex> (C++26)
tuple_element<std::complex> (C++26)

 

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

Run this code

#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);
}