Area of a triangle (using 2 extra methods) error help

EDITED..

Oke, I managed to sort everything out, except, it does not calculate the area in area() method:

Code :

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[COLOR="Red"]public static double area(double side1, double side2, double side3, double areaTri)[/COLOR]
	{
		double s = (side1 +  side2 + side3)/2;
		areaTri = Math.sqrt(s*(s - side1)*(s - side2)*(s - side3));
 
                //Returns to main() and should print out the last statement with the area
                return areaTri;	
	}

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Updated Code:

Code :

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//Calculate the area of a triangle
 
import java.util.Scanner;
import static java.lang.Math.*;
 
[COLOR="Lime"]public class MyTriangle[/COLOR]
{	
	[COLOR="Red"]public static void main(String[] args)[/COLOR]
	{		
		double areaTri=0;
		Scanner input = new Scanner(System.in);
 
		System.out.print("Enter the size of the first side: ");	
		double side1 = input.nextDouble();
 
		System.out.print("Enter the size of the second side: ");	
		double side2 = input.nextDouble();
 
		System.out.print("Enter the size of the third side: ");	
		double side3 = input.nextDouble();
 
		isValid(side1,side2, side3, areaTri);
 
		System.out.println("");
		System.out.println("The area of the triangle is "+ areaTri);	
	}	
	 //Check if the sum of side1 and side2 is greater than side3 and if not returns false
	//If true calls on method area()
	[COLOR="Red"]public static boolean isValid(double side1, double side2, double side3, double areaTri)[/COLOR]
	{
		if(side1 * side2 > side3)
		{
			area(side1,side2,side3, areaTri);
			return true;
		}
		else
		{
			System.out.println("The input is invalid!");
			return false;
		}
	}
	//calculates area of the triangle assuming conditions are met at method isValid()
	[COLOR="red"]public static double area(double side1, double side2, double side3, double areaTri)[/COLOR]
	{
		double s = (side1 +  side2 + side3)/2;
		areaTri = Math.sqrt(s*(s - side1)*(s - side2)*(s - side3));
		return areaTri;	
	}
}

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Quote:

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, it does not calculate the area in area() method:

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What is it supposed to do in that method?
Do you have a question?

If you need help debugging your code, I suggest that you separate out all the subexpressions in the sqrt() method call and print them out to see if they are computing to the values you expect.

I managed to fix it in the main():

From:

Code :

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System.out.println("The area of the triangle is "+ areaTri);

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To:

Code :

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System.out.println("The area of the triangle is "+ area(side1,side2,side3,areaTri));

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This solved the problem and lead to another. How do I round it off to 1 decimal place. Right now the output would look something like this:

0.7261843774138906

Quote:

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How do I round it off to 1 decimal place

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A couple of ways
The printf() has formatting strings
The DecimalFormat class will format a number.

I decided to use printf() since I'm more familiar with it, but it doesnt seem to work the same:

In C this would normally work:

Code :

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printf("The area of the triangle is %0.1f", area(side1,side2,side3,areaTot));

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I get a format specifier error in java when running:

Code :

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System.out.printf("The area of the triangle is %0.1f", area(side1,side2,side3,areaTot));

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Have you looked up the error message to see what it means? It could tell you what the problem is.

I know what it means...the format specifier "%0.1f" doesnt work, my question is how could I interprate this into java to show a single decimal place.

Try changing it. See the Formatter class for descriptions.

Oke, I figured it out with the help of your link.

My problem was the 0 in %0.1f. It should look like this: %.1f

Thank you!

You're welcome. Most of it is in the doc.