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

 

C++

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Feature test macros (C++20)

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Technical specifications

Symbols index

External libraries

 

Numerics library

Common mathematical functions
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Mathematical constants (C++20)
Basic linear algebra algorithms (C++26)
Floating-point environment (C++11)
Complex numbers
Numeric array (valarray)
Pseudo-random number generation
Factor operations
gcd (C++17)	lcm (C++17)
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midpoint (C++20)	lerp (C++20)
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add_sat (C++26) sub_sat (C++26) saturate_cast (C++26)	mul_sat (C++26) div_sat (C++26)
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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)
Bit operations
has_single_bit (C++20)     bit_cast (C++20) bit_ceil (C++20) bit_floor (C++20) bit_width (C++20) rotl (C++20) rotr (C++20)	popcount (C++20) countl_zero (C++20) countl_one (C++20) countr_zero (C++20) countr_one (C++20) byteswap (C++23) endian (C++20)

 

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);
}