std::abs,std::labs,std::llabs,std::imaxabs (3) - Linux Man Pages

NAME

std::abs,std::labs,std::llabs,std::imaxabs - std::abs,std::labs,std::llabs,std::imaxabs

Synopsis

Defined in header <cmath> (since C++17)
int abs( int n );
long abs( long n );
long long abs( long long n ); (since C++11)
long labs( long n );
long long llabs( long long n ); (since C++11)
std::intmax_t abs( std::intmax_t n ); (since C++11)
std::intmax_t imaxabs( std::intmax_t n ); (since C++11)

Computes the absolute value of an integer number. The behavior is undefined if the result cannot be represented by the return type.

If std::abs is called with an argument of type X such that std::is_unsigned<X>::value is true and X cannot be converted to int by integral_promotion, the program is ill-formed. (since C++17)

Parameters

n - integer value

Return value

The absolute value of n (i.e. |n|), if it is representable.

Notes

In 2's complement systems, the absolute value of the most-negative value is out of range, e.g. for 32-bit 2's complement type int, INT_MIN is -2147483648, but the would-be result 2147483648 is greater than INT_MAX, which is 2147483647.

Example

// Run this code

#include <iostream>
#include <cstdlib>
#include <climits>

int main()
{
std::cout << "abs(+3) = " << std::abs(3) << '\n'
<< "abs(-3) = " << std::abs(-3) << '\n';

// std::cout << std::abs(INT_MIN); // undefined behavior on 2's complement systems
}

Output:

abs(+3) = 3
abs(-3) = 3

abs(float)
fabs
fabsf
fabsl absolute value of a floating point value (|x|)
(function)

(C++11)
(C++11)
returns the magnitude of a complex number
abs(std::complex) (function template)
applies the function std::abs to each element of valarray
abs(std::valarray) (function template)