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Thread: Rounding with printf

  1. #1
    Junior Member
    Join Date
    Sep 2013
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    Default Rounding with printf

    import java.util.Scanner;
    public class BouncingBall
      public static void main(String[] args)
        Scanner keyboard = new Scanner(System.in);
        int bounce = 0, time = 0;
        double height = 0.0;
        double velocity = 0;
        System.out.println("Enter the initial velocity of the ball: ");
        velocity = keyboard.nextDouble();
          System.out.print("Time: % Height: 1.1f",
                                   time, height);
          time ++;
          height += velocity;
          velocity -= 32;
          if (height < 0)
            height *= -0.5;
            velocity *= -0.5;
        } while (bounce < 5);

    I need all height values in this program to be rounded to the nearest 0.1. The part after printf is what I wrote down from what my professor said to do. However, the program is not running properly. The program does run properly when I do this instead:

    System.out.println("Time: " + time + " Height: " + height);
          time ++;

    However, the Height values don't get rounded to the nearest 0.1. How to I make it so the program rounds the height values to the nearest 0.1 using printf?

  2. #2
    Super Moderator
    Join Date
    Jun 2013
    So. Maryland, USA
    My Mood
    Thanked 698 Times in 680 Posts

    Default Re: Rounding with printf

    I think your note taking wasn't so good. And you say there's a printf() statement in the code you posted, but I see a print(). Try playing with the following instead:

          System.out.printf("Time: %d Height: %1.1f\n",
                                   time, height);

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