Basic conversion program - some unexpected results

[Jose Castillo]

Hi there, I am making a basic conversion program in java for one of my classes, and am getting a few odd answers. Here's my code:

public class Conversion {
    public static int celsiusToFahrenheit(int temp){
      int Fahrenheit = ((9/5) * temp) + 32;
      return Fahrenheit;
    }
    public static int fahrenheitToCelsius(int temp){
        int Celsius = (5/9) * (temp - 32);
        return Celsius;
    }
    public static int metersToInches(int meters){
        int inches = meters * 39;
        return inches;
    }
    public static int inchesToMeters(int inches){
        int meters = inches/39;
        return meters;
    }
    public static double celsiusToFahrenheit(double temp){
       double Fahrenheit = (9.0/5.0) * temp + 32.;
       return Fahrenheit;
    }
    public static double fahrenheitToCelsius(double temp){
        double Celsius = (5.0/9.0) * (temp - 32.0);
        return Celsius;
    }
    public static double metersToInches(double meters){
        double inches = meters * 39.370;
        return inches;
    }
    public static double inchesToMeters(double inches){
        double meters = inches/39.370;
        return meters;
    }
}

I'm getting a few errors:

For int meters->inches, I got 156 instead of an expected 157.
For int Cel - > Far, I got -8 instead of an expected -40
For int Far - Cel I got 0 instead of an expected 100.
I also got an error: Failed: Non-private constructor method: public conversion()


Any pointers would be much appreciated.

[Bear Bibeault]

Answer in 3 seconds: what's the integer value of 5/9?

[Jose Castillo]

Bear Bibeault wrote:Answer in 3 seconds: what's the integer value of 5/9?

Oh, duh, zero. Thanks for pointing out that silly mistake I made. That solved it

[Bear Bibeault]

[Campbell Ritchie]

You will have similar problems with inches to meters.

By the way, you can get away without declaring a local variable

public static double kgToPounds(double kg)
{
   return kg * 2.205;
}