Processing 1.0 - Processing Discourse - why is the random() method not static?

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Index › Programming Questions & Help › Syntax Questions › why is the random() method not static

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why is the random() method not static? (Read 732 times)

Xiaohan Zhang YaBB Newbies Offline Posts: 6	why is the random() method not static? May 11^th, 2009, 4:07pm Just a quick question: why are the random methods in PApplet not static? It's quite annoying to be able to use static imports for cos(), ceil(), and every other mathematic function, but not for random().
	There is no time but the present

Cedric YaBB Moderator Offline Posts: 1838	Re: why is the random() method not static? Reply #1 - May 11^th, 2009, 5:00pm You can use http://processing.org/reference/randomSeed_.html randomSeed. Thats pretty useful. You can combine it and also create a random randomseed and print it out. so you get random numbers each time you start it but could recreate them if you want to.
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PhiLho

Re: why is the random() method not static?
Reply #2 - May 11^th, 2009, 10:43pm

Funnily, I knew about static import but haven't used it yet.
Somehow, Processing does a primitive (pre-Java 1.5) static import by using a pre-processor to repeat the definitions of some functions in sub-classes, to expose them as simple function in PApplet. [EDIT] Actually not really, since the functions are not static, but that's the same spirit, to expose methods as simple functions.

Your remark makes me think you use Processing with Eclipse, not within the PDE, since these functions are accessible without prefix in regular sketches...
The reason is simple: unlike other mathematical functions, random() isn't a self-sufficient function, it depends on members, at least the random seed. So it cannot be static.
You can still use Java's one, no

« Last Edit: May 12^th, 2009, 3:32am by PhiLho »

Cedric YaBB Moderator Offline Posts: 1838	Re: why is the random() method not static? Reply #3 - May 12^th, 2009, 2:42am Did i get the question wrong?
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PhiLho YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: why is the random() method not static? Reply #4 - May 12^th, 2009, 3:29am I fear so... Although you put your finger on the problem with the randomSeed reference!

Cedric YaBB Moderator Offline Posts: 1838	Re: why is the random() method not static? Reply #5 - May 12^th, 2009, 3:36am Yeah, thats what i thought when i read your answer... Ahh, now i got it i totally got it wrong last night. Was late... good to know you are always checking.
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Rick

Re: why is the random() method not static?
Reply #6 - May 30^th, 2009, 2:56pm

I don't know if this is a little off topic, but is it possible to do static import from the PDE For example, do:
import static java.lang.math.BigDecimal;
and you get:
expecting EOF
on the next line after the import.

I made an arbitrary precision square root example from the website in the following code (also where I discovered static import) work out of the PDE, but I made my class extend BigDecimal so it could access its constants like ROUND_HALF_UP so I had to do super(0); which seems meaningless to me in this context.

Quote:

import java.math.*;

void setup() {
  println(new BigSqrt(new BigDecimal(5), 1000).getResult());
}
void draw() {
}

static class BigSqrt extends BigDecimal{
  /*
  the Babylonian square root method (Newton's method)
  http://www.lykkenborg.no/java/2005/03/computing-pi-using-bigdecimal.html
  */
  static final BigDecimal TWO = new BigDecimal(2);
  BigDecimal x0 = new BigDecimal("0");
  BigDecimal x1;
  BigSqrt(BigDecimal A, final int SCALE) {
    super(0);
    x1 = new BigDecimal(Math.sqrt(A.doubleValue()));
    while (!x0.equals(x1)) {
        x0 = x1;
        x1 = A.divide(x0, SCALE, ROUND_HALF_UP);
        x1 = x1.add(x0);
        x1 = x1.divide(TWO, SCALE, ROUND_HALF_UP);
    }
  }
  BigDecimal getResult() {
    return x1;
  }
}

I figure there is a better way to do this, correct

http://r6753.com/ _{I need a job.}

PhiLho YaBB Moderator Offline Posts: 4190 Near Paris (France)	Re: why is the random() method not static? Reply #7 - May 31^st, 2009, 12:34am Quote: is it possible to do static import from the PDE? Currently no. It is not a valid Java 1.4 syntax and currently we are stuck with this syntax (unless you put the code in a .java file).

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