Basic java but i am getting an error in netbeans 6.5

Question

public class math {
     * @param args the command line arguments
    public static void main(String[] args) {
    int x = (int) Math.PI * 20.0;
    System.out.println(x);
found   : double
required: int
    int x = (int) Math.PI * 20.0;
1 error
BUILD FAILED (total time: 0 seconds)

Answer 1

aszxcv02 wrote:
i am doing a book example that the int is suppose to round pie to 3 and then multiple by 20 so the answer will be 60
i just copied straight out the book and i was suppose to get back 60.Use parentheses or - if it is exactly as you describe - multiply by 20 rather than 20.0.
The point is that when you take pi cast to an int (ie, truncated to 3) and multiply it by a double you will get a double result. The compiler complains when you try and assign this double to an int variable.
Edited by: pbrockway2 on Dec 27, 2008 2:00 PM
Slow ;(
But make sure you understand why it works. There is an order to things:
(a) Get the double Math.pi
(b) Truncate it to an int
(c) Multiply the int by the int value 20
What does int x = (int)(Math.PI * 20.0); do? Why?