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Thread: help with for loop

  1. #1
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    Default help with for loop

    Hi, I work in a lab that uses Java to control a light array. I have very little experience with Java. We're currently using the script below that runs for 6 hours. I have been trying to extend the run time to 12 hours. I tried changing the condition to " i < 1440 " and it will not compile. It says "Compiling.... Infinite loop in code." Ultimately, I would like it to loop for 12hrs then keep the light intensity at "0" for 12hrs and repeat that indefinitely. Can anyone help? Thanks in advance.


    /**
    * License header here
    */

    /**
    * New Script
    */

    light=390
    dark=0
    time="180s"
    limit = 3000;

    for (var i = 0; i < 720; i++){
    set_intensity(54)
    wait("1s")
    set_intensity(107)
    wait("1s")
    set_intensity(255)
    wait("1s")
    set_intensity(2000)
    wait("2s")
    set_intensity(255)
    wait("1s")
    set_intensity(107)
    wait("1s")
    set_intensity(54)
    wait("1s")
    set_intensity(0)
    wait("22s")
    }

  2. #2
    Super Moderator Norm's Avatar
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    Default Re: help with for loop

    What does the value 720 represent? Instead of hardcoding a value, use a variable with a proper name that is given a value using an expression. For example:
    int timeToRunInSec = 12*60*60; // number of seconds in 12 hours with 60 min/hr, 60 sec/min

    How long does it take for the code inside of the loop to execute? Say 30 seconds per iteration
    Then for the loop to execute for 12 hours takes this number of iterations:
    number of seconds in 12 hours / 30 sec per iteration

    Please copy the exact text of any compiler error message and paste it here.
    Also post the code that caused the errors.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: help with for loop

    Also, the value in set_intensity(255) suggests an 8-bit integer with a range of 256 [0..255], or some larger multiple thereof. But there's also an entry for set_intensity(2000)
    If 2000 were a reasonable value, then it would follow that 250 would be a reasonable fraction of it.

    Valid range of values is something that can be added into comment blocks, which is then read and displayed in IDE mouse-over windows
      /**
       * Set light level
       * @param intensity [0..255]
       */
      public static void set_intensity(int intensity){
        // code
      }
    Screenshot
    Last edited by AngleWyrm; January 6th, 2023 at 08:58 PM.

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    Default Re: help with for loop

    @Norm: I believe 720 is part of the condition. As long as the variable " i " is less than 720, the script will loop (i < 720). Do we just use the timeToRunInSec in place of the condition?

    @AngleWyrm: The intensities are specific light settings that the researchers need the array to be set at for each time point.

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    Default Re: help with for loop

    Do we just use the timeToRunInSec in place of ...
    In place of the 720.
    Its value would be the number of times you want to loop to iterate.
    If you don't understand my answer, don't ignore it, ask a question.

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