std::abs(std::complex)

 

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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!= (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)
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pow   sqrt
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sin   cos tan asin (C++11) acos (C++11) atan (C++11)
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sinh   cosh tanh asinh (C++11) acosh (C++11) atanh (C++11)
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tuple_size<std::complex> (C++26)
tuple_element<std::complex> (C++26)

 

Defined in header <complex>
template< class T > T abs( const complex<T>& z );

Returns the magnitude of the complex number z.

Parameters

z

-

complex value

Return value

If no errors occur, returns the absolute value (also known as norm, modulus, or magnitude) of z.

Errors and special cases are handled as if the function is implemented as std::hypot(std::real(z), std::imag(z)).

Example

Run this code

#include <complex>
#include <iostream>
 
int main()
{
    std::complex<double> z(1, 1);
    std::cout << z << " cartesian is rho = " << std::abs(z)
              << " theta = " << std::arg(z) << " polar\n";
}

Output:

(1,1) cartesian is rho = 1.41421 theta = 0.785398 polar

See also

arg	returns the phase angle (function template)
polar	constructs a complex number from magnitude and phase angle (function template)
abs(int)labsllabs (C++11)	computes absolute value of an integral value (\(\small{|x|}\)|x|) (function)
abs(float)fabsfabsffabsl (C++11)(C++11)	absolute value of a floating point value (\(\small{|x|}\)|x|) (function)
hypothypotfhypotl (C++11)(C++11)(C++11)	computes square root of the sum of the squares of two or three(since C++17) given numbers (\(\scriptsize{\sqrt{x^2+y^2}}\)√x2 +y2 ), (\(\scriptsize{\sqrt{x^2+y^2+z^2}}\)√x2 +y2 +z2 )(since C++17) (function)
abs(std::valarray)	applies the function abs to each element of valarray (function template)
C documentation for cabs