function
<cmath> <ctgmath>

abs

     double abs (double x);      float abs (float x);long double abs (long double x);
     double abs (double x);      float abs (float x);long double abs (long double x);     double abs (T x);           // additional overloads for integral types
Compute absolute value
Returns the absolute value of x: |x|.

These convenience abs overloads are exclusive of C++. In C, abs is only declared in <stdlib.h> (and operates on int values).

Since C++11, additional overloads are provided in this header (<cmath>) for the integral types: These overloads effectively cast x to a double before calculations (defined for T being any integral type).

Parameters

x
Value whose absolute value is returned.

Return Value

The absolute value of x.

Example

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// cmath's abs example
#include <iostream>     // std::cout
#include <cmath>        // std::abs

int main ()
{
  std::cout << "abs (3.1416) = " << std::abs (3.1416) << '\n';
  std::cout << "abs (-10.6)  = " << std::abs (-10.6) << '\n';
  return 0;
}

Output:

abs (3.1416) = 3.1416
abs (-10.6) = 10.6


See also