Solved

What is the problem with 'double'?

Posted on 2004-04-12
5
253 Views
Last Modified: 2010-03-31
Here I attach the code segment and it output:

Code:

public static void main(String args[]){
    for(double d = 1; d >= 0; d -= 0.2){
        System.out.println(d);
    }
}

Output:

1.0
0.8
0.6000000000000001
0.4000000000000001
0.20000000000000007
5.551115123125783E-17

Why is this happened? and How to solve this problem if I am expecting the output of:

1.0
0.8
0.6
0.4
0.2
0.0

Thank You.
0
Comment
Question by:b612_forever
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
5 Comments
 
LVL 15

Assisted Solution

by:Javatm
Javatm earned 20 total points
ID: 10810092
This should solve your problem :

public static void main(String args[]) {

    DecimalFormat d1 = new DecimalFormat("0.0");

    for(double d = 1; d >= 0; d -= 0.2) {
    System.out.println(d1.format(d));
    }
}

Hope that helps . . .
Javatm
0
 
LVL 30

Assisted Solution

by:Mayank S
Mayank S earned 20 total points
ID: 10810540
Well, precision-related matters always come into picture while dealing with floats and sometimes also with doubles. You should never look for or compare exact values but keep a margin for error-tolerance while dealing with them.
0
 
LVL 24

Accepted Solution

by:
sciuriware earned 20 total points
ID: 10810805
Remember that a computer is binary organised: many floating numbers can't be represented in float or double
like PI in the decimal system.
;JOOP!
0
 
LVL 1

Author Comment

by:b612_forever
ID: 10810958
Since Javatm provide the solution and mayankeagle,scuriware provide the explanation, I add 10 point for this question and split it to three.
0
 
LVL 30

Expert Comment

by:Mayank S
ID: 10810991
Glad to help ;-)
0

Featured Post

On Demand Webinar: Networking for the Cloud Era

Ready to improve network connectivity? Watch this webinar to learn how SD-WANs and a one-click instant connect tool can boost provisions, deployment, and management of your cloud connection.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This was posted to the Netbeans forum a Feb, 2010 and I also sent it to Verisign. Who didn't help much in my struggles to get my application signed. ------------------------- Start The idea here is to target your cell phones with the correct…
Are you developing a Java application and want to create Excel Spreadsheets? You have come to the right place, this article will describe how you can create Excel Spreadsheets from a Java Application. For the purposes of this article, I will be u…
Viewers will learn about arithmetic and Boolean expressions in Java and the logical operators used to create Boolean expressions. We will cover the symbols used for arithmetic expressions and define each logical operator and how to use them in Boole…
Viewers will learn one way to get user input in Java. Introduce the Scanner object: Declare the variable that stores the user input: An example prompting the user for input: Methods you need to invoke in order to properly get  user input:

734 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question