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`Div1' example program: demonstrates how to avoid the pitfall of integer division
Div1.java
// Div1.java
// A program that works out 2/5.
// Kevin Boone, May 1999
import java.applet.Applet;
import java.awt.*;
public class Div1 extends Applet
{
public void paint (Graphics g)
{
// Note that not only must the result be stored in a
// variable of type ``double'', (or ``float'', but not
// ``int'', the numbers have to be given as 2.0 and
// 5.0, not 2 and 5. The problem is that the computer only
// does one thing at a time. If I say `2/5', it does the
// division using whole numbers (integers), then puts the
// result into the variable `result'. But by then it is too
// late: the decimal part has already been lost. By saying
// 2.0 and not 2, the Java compiler knows that it has to
// do the calculation using the decimal part as well!
double result = 2.0 / 5.0;
g.drawString ("2 / 5", 20, 20);
g.drawString (Double.toString(result), 20, 40);
}
}
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