use decimals in java?

rabbit2345 · 03-07-2008, 10:04 PM

hi,
I want to write a small program that averages some numbers together, but to do that, I can do the adding part, but I can't get the program to output a decimal. I f i use java.lang.Math.round(total,2) then i get this error message:

Code:

brian@brian-linux:~/Documents/java> javac avg.java
avg.java:514: cannot find symbol
symbol  : method Round(double,int)
location: class java.lang.Math
double round = java.lang.Math.round(total,2);
                   ^
1 error

did I do something wrong?

thanks,

rabbit2345

nullmind · 03-08-2008, 12:08 AM

The Math.round method only takes one argument. It does not allow you to truncate based on decimal places. See the API reference:

http://java.sun.com/javase/6/docs/ap...l#round(double)

What you want can be accomplished like this though:

Code:

public class Sum{
	/**
		Usage: java Sum <number>...
	*/
	public static void main(String[] args){
		float sum = 0;
		
		for(String str : args){
			sum += Float.parseFloat(str);			
		}
		
		System.out.printf("%02.2f\n", sum);
	}
}

You could also surround the Float.parseFloat to catch the NumberFormatException if an invalid value is passed.

Cheers,
Kris