std::norm(std::complex)

 

C++

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Technical Specifications

 

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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!= 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
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)

 

Defined in header <complex>
template< class T > T norm( const complex<T>& z );	(1)
long double norm( long double z );	(2)	(since C++11)
template< class DoubleOrInteger > double norm( DoubleOrInteger z );	(3)	(since C++11)
float norm( float z );	(4)	(since C++11)

Returns the squared magnitude of the complex number z.

(since C++11)Additional overloads are provided for float, double, long double, and all integer types, which are treated as complex numbers with zero imaginary component.

Parameters

z

-

complex value

Return value

the squared magnitude of z

Notes

The norm calculated by this function is also known as field norm or absolute square.

The Euclidean norm of a complex number is provided by std::abs, which is more costly to compute. In some situations, it may be replaced by std::norm, for example, if abs(z1) > abs(z2) then norm(z1) > norm(z2).

See also

abs(std::complex)	returns the magnitude of a complex number (function template)
conj	returns the complex conjugate (function template)
polar	constructs a complex number from magnitude and phase angle (function template)