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Java random number generator help.

  1. Jul 8, 2010 #1
    Hi, I'm trying to get it so that when the program initiates, if the random number is greater than 3, I turn left. here is what I have in summary;

    int rt=3;
    Random ra = new Random();
    for (int c = 6; c <12; ++c);

    the error says; operator < cannot be applied to int,java.util.Random
    if this is the case, how can i get use the random number generator toward my end? I want the random number generator to be the source of "randomly occuring actions" for my robot.
  2. jcsd
  3. Jul 8, 2010 #2


    Staff: Mentor

    I added [ code] tags.
    There are several things wrong with your code.
    1) ra is an instance of the Random class. It is not a random number. Look http://download.oracle.com/docs/cd/E17476_01/javase/1.4.2/docs/api/java/util/Random.html [Broken] for a summary of the methods that are exposed by this class.

    The error you are getting says essentially that you cannot compare a number and a class instance.
    2) Your for loop is confusing (to some). What are you trying to get it to do? As it is now, all it does is count from 6 to 12 - nothing more.
    3) You have a pair of braces following the for statement. Why are they there? If you removed them it would make no difference in what your code produces.
    Last edited by a moderator: May 4, 2017
  4. Jul 9, 2010 #3
    int x = ra.nextInt();
    which should give you a value from 0-31, or
    double x = ra.nextDouble();
    which should be between 0.0 and 1.0

    Also follow all the advice of the previous poster,
    and pay some attention to Random.setSeed()
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