C# / .NET - Math.Abs() method example

The Math.Abs() function returns the absolute value of a number. 

The absolute value of the number x denoted |x|, is the non-negative value of x without regard to its sign.

Popular usage examples:

using System;

public class Program
{
    public static void Main(string[] args) 
    {
        Console.WriteLine( Math.Abs( 2 )); // 2
        Console.WriteLine( Math.Abs(-2 )); // 2
                           
        Console.WriteLine( Math.Abs( 2.54)); // 2.54
        Console.WriteLine( Math.Abs(-2.54)); // 2.54
                           
        Console.WriteLine( Math.Abs(  0   )); // 0
        Console.WriteLine( Math.Abs( 3 + 5)); // 8
        Console.WriteLine( Math.Abs( 3 - 5)); // 2
    }
}

1. Documentation

namespace System
{
    public static class Math
    {
        // ...
        public static decimal Abs(decimal value) { ... }
        public static double Abs(double value) { ... }
        public static short Abs(short value) { ... }
        public static int Abs(int value) { ... }
        public static long Abs(long value) { ... }
        public static sbyte Abs(sbyte value) { ... }
        public static float Abs(float value) { ... }
        // ...
    }
}

2. Math.Abs() custom implementation

using System;

class Program
{
    static double Abs(double x) 
    {
        if (x < 0) {
            return -x;
        }
        return x;
    }

    static void Main(string[] args) 
    {
        Console.WriteLine( Abs(2.0) ); // 2
        Console.WriteLine( Abs(-2.0)); // 2
        Console.WriteLine( Abs(0.0) ); // 0
    }
}

References

1. Absolute value - wikipedia