not asking user for temp to convert just printing print line statements.

package celsiusfahrenheitconverter;
import java.util.Scanner;

/** This java code reads
 *  Fahrenheit temperature the
 * user enters and displays back
 * temperature in Celsius. This also
 * Reads the Celsius temperature
 * entered and displays back
 * Fahrenheit temperature.
 *
 * @author 
 */
public class CelsiusFahrenheitConverter
{

	/**
	 * @param args the command line arguments
	 */
	public static void main(String[] args)
	{
		  // declare variables
		String from;
		String to;
		String temp;
		int choice;
		int fahrenheit;
		int celsius;

		Scanner input = new Scanner(System.in);
	   
		do
		{
			choice = -1;
			System.out.println("Convert tmperature:");
			System.out.println(" Convert from Fahrenheit to Celsius:");
			System.out.println(" Convert from Celsius to Fahrenheit:");
			System.out.println("Enter 3 - Exit:");
			choice = input.nextInt();

		switch (choice)
		{
			// case 1 asks user for a Fahrenheit temp to convert to Celsius
			// case 2 asks user for a Celsius temp to convert to Fahrenheit
		   case 1:
				 
				System.out.println("Enter the temperature in Fahrenheit:");
				fahrenheit = input.nextInt();
				celsius = convertToCelsius(fahrenheit);
				from = "Fahrenheit";
				to = "Celsius";
				break;

		   case 2:
				 
				System.out.println("Enter the temperature in Celsius:");
				celsius = input.nextInt();
				fahrenheit = convertToFahrenheit(celsius);
				from = "Celsius";
				to = "Fahrenheit";
				break;
			  default:
					continue; // no input or output
		}

				 System.out.print("\n");
				 System.out.print(fahrenheit);
			  
				 System.out.print(from);
				 System.out.print("=");
				 System.out.print(celsius);
			   
				 System.out.print(to);
				 System.out.print('\n');
		}
			while (choice != 3);
	}

			/**
	 * Converts form Celsius to
	 * Fahrenheit
	 * @param temp The temperature
	 * in Celsius
	 * @return The temperature in
	 * Fahrenheit
	 */

	public static int convertToFahrenheit(int temp)
	{
		return (9 * temp)/ 5 + 32;
	}

	/**
	 * Converts from Fahrenheit
	 * to Celsius
	 * @param temp the temperature
	 * in Fahrenheit
	 * @return the temperature in Celsius
	 */

	 public static int convertToCelsius(int temp)
	 {
		 return (temp - 32) / 9 * 5;
	 }

}

/*run:
Convert tmperature:
 Convert from Fahrenheit to Celsius:
 Convert from Celsius to Fahrenheit:
Enter 3 - Exit:*/

This post has been edited by gmillerlight: 07 June 2009 - 06:54 PM

I am not sure what you are asking but I believe both of your equations for conversion are wrong. You also have to take into account that 5/9 won't return .55555 etc, it will return 0 because you are doing integer division. Make sure you convert them to doubles and use doubles throughout your equation. If you want it to return int, cast it to an int at the end.

return (int)(((9.0 / 5.0) * (double)temp) + 32.0);

and 

return (int)((5.0 / 9.0) * ((double)temp - 32.0));

Lastly you will need to take a look at the printing at the end and watch which labels you are printing because they are backwards. Don't switch the "to" and "from" variable labels because you are then not switching what variables you print.

Good luck.

Quote

package celsiusfahrenheitconverter;
import java.util.Scanner;

/** This java code reads
 *  Fahrenheit temperature the
 * user enters and displays back
 * temperature in Celsius. This also
 * Reads the Celsius temperature
 * entered and displays back
 * Fahrenheit temperature.
 *
 * @author 
 */
public class CelsiusFahrenheitConverter
{

	/**
	 * @param args the command line arguments
	 */
	public static void main(String[] args)
	{
		  // declare variables
		String from;
		String to;
		String temp;
		int choice;
		int fahrenheit;
		int celsius;

		Scanner input = new Scanner(System.in);
	   
		do
		{
			choice = -1;
			System.out.println("Convert temperature:");
			System.out.println(" Convert from Fahrenheit to Celsius:");
			System.out.println(" Convert from Celsius to Fahrenheit:");
			System.out.println("Enter 3 - Exit:");
			choice = input.nextInt();

		switch (choice)
		{
			// case 1 asks user for a Fahrenheit temp to convert to Celsius
			// case 2 asks user for a Celsius temp to convert to Fahrenheit
		   case 1:
				 
				System.out.println("Enter the temperature in Fahrenheit:");
				fahrenheit = input.nextInt();
				celsius = convertToCelsius(fahrenheit);
				from = "Celsius";
				to = "Fahrenheit";
				break;

		   case 2:
				 
				System.out.println("Enter the temperature in Celsius:");
				celsius = input.nextInt();
				fahrenheit = convertToFahrenheit(celsius);
				from = "Fahrenheit";
				to = "Celsius";
				break;
			  default:
					continue; // no input or output
		}

				 System.out.print("\n");
				 System.out.print(fahrenheit);
			  
				 System.out.print(from);
				 System.out.print("=");
				 System.out.print(celsius);
			   
				 System.out.print(to);
				 System.out.print('\n');
		}
			while (choice != 3);
	}

			/**
	 * Converts form Celsius to
	 * Fahrenheit
	 * @param temp The temperature
	 * in Celsius
	 * @return The temperature in
	 * Fahrenheit
	 */

	public static int convertToFahrenheit(int temp)
	{
		return (int)(((9.0 / 5.0) * (double)temp) + 32.0);


	}

	/**
	 * Converts from Fahrenheit
	 * to Celsius
	 * @param temp the temperature
	 * in Fahrenheit
	 * @return the temperature in Celsius
	 */

	 public static int convertToCelsius(int temp)
	 {
		 return (int)((5.0 / 9.0) * ((double)temp - 32.0));

	 }

}
/*run:
Convert tmperature:
 Convert from Fahrenheit to Celsius:
 Convert from Celsius to Fahrenheit:
Enter 3 - Exit:
59
Convert tmperature:
 Convert from Fahrenheit to Celsius:
 Convert from Celsius to Fahrenheit:
Enter 3 - Exit:
59
Convert tmperature:
 Convert from Fahrenheit to Celsius:
 Convert from Celsius to Fahrenheit:
Enter 3 - Exit:
3
BUILD SUCCESSFUL (total time: 1 minute 12 seconds)
*/


	

This post has been edited by gmillerlight: 08 June 2009 - 04:42 AM

i'm guessing it's okay now

Quote

okay i was gonna do this earlier, but i wasn't sure of something. click here now it's in C++, but it's set up relatively easy to convert. just make a new variable and then return the new variable

for example if you change the cout<< to return then it would work. hope that helps


PLEASE READ THE INSTRUCTION IN THIS POST CAREFULLY

This post has been edited by computerfox: 08 June 2009 - 07:55 AM

*facepalm* i'll help you out dude...

public double convertTemp(double temp,char from,char to)
{
		  from=from.toUpperCase();
		  to=to.toUpperCase();
		  int answer1=from.compareTo("C");
		  int answer2=to.compareTo("F");

	  //from c to f
		  if(answer1==0&&answer2==0)
	  {
		  return (((temp/5)*9)+32);
	  }
	  
	  //from f to c
		  answer1=from.compareTo("F");
		  answer2=to.compareTo("C");
	  if(answer1==0&&answer2==0)
	  {

		   return (((temp-32)*5)/9);
	  }
	  
	
}

hope that helps