Sometimes the default order of evaluation isn't what you want. For instance, the formula to change a Fahrenheit temperature to a Celsius temperature is C = (5/9) (F - 32) where C is degrees Celsius and F is degrees Fahrenheit. You must subtract 32 from the Fahrenheit temperature before you multiply by 5/9, not after. You can use parentheses to adjust the order much as they are used in the above formula. The next program prints a table showing the conversions from Fahrenheit and Celsius between zero and three hundred degrees Fahrenheit every twenty degrees.
// Print a Fahrenheit to Celsius table
class FahrToCelsius {
public static void main (String args[]) {
// lower limit of temperature table
double lower = 0.0;
// upper limit of temperature table
double upper = 300.0;
// step size
double step = 20.0;
double fahr = lower;
while (fahr <= upper) {
double celsius = (5.0 / 9.0) * (fahr-32.0);
System.out.println(fahr + " " + celsius);
fahr = fahr + step;
}
}
}