C# Double Equals(Double)

Description

Double Equals(Double) returns a value indicating whether this instance and a specified Double object represent the same value.

Syntax

Double.Equals(Double) has the following syntax.


public bool Equals(
  double obj
)

Parameters

Double.Equals(Double) has the following parameters.

obj - A Double object to compare to this instance.

Returns

Double.Equals(Double) method returns true if obj is equal to this instance; otherwise, false.

Example

The following example reports that the Double value .333333 and the Double value returned by dividing 1 by 3 are unequal.


using System;/*from  w ww  . j a  v a 2  s  . c om*/

public class MainClass{
  public static void Main(String[] argv){  
    // Initialize two doubles with apparently identical values 
    double double1 = .33333;
    double double2 = 1/3;
    // Compare them for equality
    Console.WriteLine(double1.Equals(double2));    // displays false

  }
}

The code above generates the following result.

Example 2

The following example compares .33333 and 1/3, the two Double values that the previous code example found to be unequal. In this case, the values are equal.


using System;//w w w  .ja  v a  2  s  .  c om

public class MainClass{
  public static void Main(String[] argv){  
    // Initialize two doubles with apparently identical values 
    double double1 = .333333;
    double double2 = (double) 1/3;
    // Define the tolerance for variation in their values 
    double difference = Math.Abs(double1 * .00001);
    
    // Compare the values 
    // The output to the console indicates that the two values are equal 
    if (Math.Abs(double1 - double2) <= difference)
       Console.WriteLine("double1 and double2 are equal.");
    else
       Console.WriteLine("double1 and double2 are unequal.");

  }
}

The code above generates the following result.