Paraknight - 1 year ago 72
Java Question

How do you round a decimal when using the if statement in Java?

I am new to Java and I am coding a credit card Java assignment where you add charges to a credit card and add the interest with the charge. I coded an interest using the If statement but it outputs to a decimal that is not rounded.

``````public class Credit_Card
{
public static void main (String []args)
{
Scanner c = new Scanner (System.in);
double num1, num2, interest, newBalance, min = 0;

int num3 = 50;

System.out.println ("What is the previous balance?");
num1 = c.nextInt();

System.out.println ("What is the total amount of additional       charges?");
num2 = c.nextInt();

interest = num2;

if (num2 == 0)
interest = (interest + 0); //There is no interest if num2 is 0

if (num2 > 0)
interest = (interest*(2.0f/100.0f)); //total amount of money owed is multiplied by 2 percent

newBalance = num1 + num2 + interest;

System.out.println ("CS CARD International Statement");
System.out.println ("===============================");
System.out.println ("");
System.out.println ("Previous Balance:      \$" + num1 );
System.out.println ("Additional Charges:    \$" + num2 );
System.out.println ("Interest:              \$" + interest );
System.out.println ("");
System.out.println ("New Balance:           \$" + newBalance);
System.out.println ("");

if (newBalance < 50)
min = newBalance;

if(newBalance >= 50 && newBalance <= 300)
min = num3;

if(newBalance > 301)
min = (newBalance*(20.0f/100.0f));

System.out.println ("Minimum Payment:       \$" + min);
}
}
``````

The output look like this:

``````What is the previous balance?
1000
What is the total amount of additional charges?
25
CS CARD International Statement
===============================

Previous Balance:      \$1000.0
Interest:              \$0.4999999888241291

New Balance:           \$1025.4999999888241

Minimum Payment:       \$205.100003053993
``````

I think that because the interest is an everlasting decimal, it screws up everything else. Instead of the Interest being "0.49999999999", I want it to like like "0.50". Thank you very much in advance for any help.

`String.format ("%.2f", var);` where `var` is your newBalance, etc.