function template
<complex>

std::abs

template<class T> T abs (const complex<T>& x);
Absolute value of complex
Returns the absolute value of the complex number x.

The absolute value of a complex number is its magnitude (or modulus), defined as the theoretical distance between the coordinates (real,imag) of x and (0,0) (applying the Pythagorean theorem).

This function is overloaded in <cstdlib> for integral types (see cstdlib abs), in <cmath> for floating-point types (see cmath abs), and in <valarray> for valarrays (see valarray abs).

Parameters

x
Complex value.

Return value

The absolute value of x.
T is the type of the components of the complex type (i.e., its value type).

Example

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// abs complex example
#include <iostream>     // std::cout
#include <complex>      // std::complex, std::abs

int main ()
{
  std::complex<double> mycomplex (3.0,4.0);

  std::cout << "The absolute value of " << mycomplex << " is " << std::abs(mycomplex) << '\n';

  return 0;
}


Output:

The absolute value of (3,4) is 5

See also

arg
Phase angle of complex (function template )
polar
Complex from polar components (function template )
abs (cstdlib)
Absolute value (function )