BigInteger.Abs(BigInteger) Method


Gets the absolute value of a BigInteger object.

 static System::Numerics::BigInteger Abs(System::Numerics::BigInteger value);
public static System.Numerics.BigInteger Abs (System.Numerics.BigInteger value);
static member Abs : System.Numerics.BigInteger -> System.Numerics.BigInteger
Public Shared Function Abs (value As BigInteger) As BigInteger



A number.



The absolute value of value.


The following example uses the Abs method to convert a BigInteger value from two's complement representation to sign-and-magnitude representation before serializing it to a file. Data in the file is then deserialized and assigned to a new BigInteger object.

using System;
using System.IO;
using System.Numerics;
using System.Runtime.Serialization.Formatters.Binary;

[Serializable] public struct SignAndMagnitude
   public int Sign;
   public byte[] Bytes;

public class Example
   public static void Main()
      FileStream fs;
      BinaryFormatter formatter = new BinaryFormatter();

      BigInteger number = BigInteger.Pow(Int32.MaxValue, 20) * BigInteger.MinusOne;
      Console.WriteLine("The original value is {0}.", number);
      SignAndMagnitude sm = new SignAndMagnitude();
      sm.Sign = number.Sign;
      sm.Bytes = BigInteger.Abs(number).ToByteArray();

      // Serialize SignAndMagnitude value.
      fs = new FileStream(@".\data.bin", FileMode.Create);
      formatter.Serialize(fs, sm);

      // Deserialize SignAndMagnitude value.
      fs = new FileStream(@".\data.bin", FileMode.Open);
      SignAndMagnitude smRestored = (SignAndMagnitude) formatter.Deserialize(fs);
      BigInteger restoredNumber = new BigInteger(smRestored.Bytes);
      restoredNumber *= sm.Sign;
      Console.WriteLine("The deserialized value is {0}.", restoredNumber);
// The example displays the following output:
//    The original value is -4.3510823966323432743748744058E+186.
//    The deserialized value is -4.3510823966323432743748744058E+186.
Imports System.IO
Imports System.Numerics
Imports System.Runtime.Serialization.Formatters.Binary

<Serializable> Public Structure SignAndMagnitude
   Dim Sign As Integer
   Dim Bytes() As Byte
End Structure

Module Example
   Public Sub Main()
      Dim fs As FileStream
      Dim formatter As New BinaryFormatter()

      Dim number As BigInteger = BigInteger.Pow(Int32.MaxValue, 20) * BigInteger.MinusOne
      Console.WriteLine("The original value is {0}.", number)
      Dim sm As New SignAndMagnitude()
      sm.Sign = number.Sign
      sm.Bytes = BigInteger.Abs(number).ToByteArray()
      ' Serialize SignAndMagnitude value.
      fs = New FileStream(".\data.bin", FileMode.Create)
      formatter.Serialize(fs, sm)
      ' Deserialize SignAndMagnitude value.
      fs = New FileStream(".\data.bin", FileMode.Open)
      Dim smRestored As SignAndMagnitude = DirectCast(formatter.Deserialize(fs), SignAndMagnitude)
      Dim restoredNumber As New BigInteger(smRestored.Bytes) 
      restoredNumber *= sm.Sign 
      Console.WriteLine("The deserialized value is {0}.", restoredNumber)      
   End Sub
End Module
' The example displays the following output:
'    The original value is -4.3510823966323432743748744058E+186.
'    The deserialized value is -4.3510823966323432743748744058E+186.


The absolute value of a number is that number without its sign, as shown in the following table.

value parameter Return value
value >= 0 value
value < 0 value * -1

The Abs method is equivalent to the Math.Abs method for the primitive numeric types.

Applies to

See also