std::abs(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>
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 hypotenuse \(\scriptsize{\sqrt{x^2+y^2}}\)√x2 +y2 and \(\scriptsize{\sqrt{x^2+y^2+z^2}}\)√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

Follow Lee on X/Twitter - Father, Husband, Serial builder creating AI, crypto, games & web tools. We are friends :) AI Will Come To Life!

Check out: eBank.nz (Art Generator) | Netwrck.com (AI Tools) | Text-Generator.io (AI API) | BitBank.nz (Crypto AI) | ReadingTime (Kids Reading) | RewordGame | BigMultiplayerChess | WebFiddle | How.nz | Helix AI Assistant