Thread: Help with formatting output into console

Good afternoon! i am working on an assignment an having a bear of a time with one of the requirements. I am to establish formatting of the console output to 2 places after the decimal, but my current code is only showing a single. Any help would be greatly appreciated!!

import java.util.Scanner;
 
public class Chpt6_Project {
 
	public static void main(String[] args) {
		Scanner input  = new Scanner(System.in);
		System.out.print("Enter the length: ");
		double length = input.nextDouble();
		System.out.print("Enter the width: ");
		double width = input.nextDouble();
		System.out.print("Enter the height: ");
		double height = input.nextDouble();
		double area = calcArea(length, width, height);
 
		System.out.printf("The surface area for a rectangular prism "+ length + " inches long, " + width + " "
				+ "inches wide, and " + height + " inches tall is " + area + " square inches. ");
 
	}
 
	public static double calcArea(double num1, double num2, double num3) {
		double area = ((num1 * num2) + (num1 * num2) + (num1 * num3) + (num1 * num3) + (num2 * num3) + (num2 * num3));
		return area;
 
	}
}

console is showing:

Enter the length: 4
Enter the width: 2
Enter the height: 1
The surface area for a rectangular prism 4.0 inches long, 2.0 inches wide, and 1.0 inches tall is 28.0 square inches.

Norm, thank you for the very quick reply. Please excuse the ignorance here, i'm a complete beginner (but loving every minute of learning), but following that guidance it would appear something along the lines of a %4.2f do the trick? establishing a 4 character string, with 2 places after the decimal? i'm getting a compiler error in eclipse when attempting to go that route? not sure if this is a result of bad formatting in the code in requesting the output or if i'm completely off base.

i just attempted to format the first 'length' variable here just for testing, but will ultimately need to format length, width, height, and area to two decimals. it let me run the program, but the console spit out the error below

import java.util.Scanner;
 
public class Chpt6_Project {
 
	public static void main(String[] args) {
		Scanner input  = new Scanner(System.in);
		System.out.print("Enter the length: ");
		double length = input.nextDouble();
		System.out.print("Enter the width: ");
		double width = input.nextDouble();
		System.out.print("Enter the height: ");
		double height = input.nextDouble();
		double area = calcArea(length, width, height);
 
		System.out.printf("The surface area for a rectangular prism %4.2d", length + " inches long, " + width + " "
				+ "inches wide, and " + height + " inches tall is " + area + " square inches. ");
 
	}
 
	public static double calcArea(double num1, double num2, double num3) {
		double area = ((num1 * num2) + (num1 * num2) + (num1 * num3) + (num1 * num3) + (num2 * num3) + (num2 * num3));
		return area;
 
	}
}

Enter the length: 4
Enter the width: 2
Enter the height: 1
Exception in thread "main" java.util.IllegalFormatPrecisionException: 2
at java.util.Formatter$FormatSpecifier.checkInteger(U nknown Source)
at java.util.Formatter$FormatSpecifier.<init>(Unknown Source)
at java.util.Formatter.parse(Unknown Source)
at java.util.Formatter.format(Unknown Source)
at java.io.PrintStream.format(Unknown Source)
at java.io.PrintStream.printf(Unknown Source)
at Chpt6_Project.main(Chpt6_Project.java:16)

same error

import java.util.Scanner;
 
public class Chpt6_Project {
 
	public static void main(String[] args) {
		Scanner input  = new Scanner(System.in);
		System.out.print("Enter the length: ");
		double length = input.nextDouble();
		System.out.print("Enter the width: ");
		double width = input.nextDouble();
		System.out.print("Enter the height: ");
		double height = input.nextDouble();
		double area = calcArea(length, width, height);
 
		System.out.printf("The surface area for a rectangular prism %4.2f", length + " inches long, " + width + " "
				+ "inches wide, and " + height + " inches tall is " + area + " square inches. ");
 
	}
 
	public static double calcArea(double num1, double num2, double num3) {
		double area = ((num1 * num2) + (num1 * num2) + (num1 * num3) + (num1 * num3) + (num2 * num3) + (num2 * num3));
		return area;
 
	}
}

Enter the length: 4
Enter the width: 2
Enter the height: 1
The surface area for a rectangular prism Exception in thread "main" java.util.IllegalFormatConversionException: f != java.lang.String
at java.util.Formatter$FormatSpecifier.failConversion (Unknown Source)
at java.util.Formatter$FormatSpecifier.printFloat(Unk nown Source)
at java.util.Formatter$FormatSpecifier.print(Unknown Source)
at java.util.Formatter.format(Unknown Source)
at java.io.PrintStream.format(Unknown Source)
at java.io.PrintStream.printf(Unknown Source)
at Chpt6_Project.main(Chpt6_Project.java:16)

--- Update ---

Thinking about this more... could it be that i haven't established a string? i know i'm not saying this correctly, but i feel like that has something to do with this....???