[source]Custom random number generator

[source]Custom random number generator - Printable Version

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+--- Thread: [source]Custom random number generator (/Thread-source-Custom-random-number-generator)

[source]Custom random number generator - 1llusion - 05-09-2013

Hi!

Inspired by this video:

I wanted to make a pseudo random number generator, where the numbers wouldn't repeat.
I got close to it.

The following object is powered by mt_rand(). I might update it so we get cryptographically stronger numbers later on.

Usage:

PHP Code:
<?php $rand_gen = new irand;
$rand = $rand_gen->rand(0, 100);?>

First argument is min number, second is max number. Third argument (if supplied) will be used as seed. All arguments are optional.
If min isn't set, the min will be set to 0.
If max isn't set, it will be set to maximum mt_rand() value (mt_getrandmax()).
If seed isn't set, PHP will generate it.

So here is the object:

PHP Code:
<?php
class irand{
    private static $arr = array(NULL); //Holds the information of already generated numbers


/*
* Outputs the number.
*/
    public function rand($min = 0, $max = FALSE, $seed = false){
        if($seed) mt_srand($seed);

        if(!$max) $max = mt_getrandmax(); //If it isn't set.

        $return = $this->generate(mt_rand($min, $max), $min, $max);
        if(!$return && !is_numeric($return)){ //Everything was tested. Start again.
            self::$arr = array(NULL);
            return $this->generate(mt_rand($min, $max), $min, $max);
        }

        return $return;

    }
/*
* Checks if a the variable was generated already.
*/
    private function exists($num){
        foreach(self::$arr as $val){
            if($val == $num) return TRUE; //Tests if the number was already generated
        }
        return FALSE;
    }

/*
* Generates the number.
*/
    private function generate($rand, $min, $max){
        if (empty(self::$arr[0]) && !is_numeric(self::$arr[0])){
            self::$arr[0] = mt_rand($min, $max);
            return self::$arr[0];
        }

        while($this->exists($rand)){
            if(count(self::$arr) == (($max - $min) +1)) return FALSE;
            $rand = mt_rand($min, $max);
        }
        self::$arr[] = $rand;
        return $rand;
    }
}

?>

example code:

PHP Code:
<?php require_once 'object.php';

$rand_gen = new irand;


$num = array();
for($temp = 0; $temp <= 100; $temp++){
    $rand = $rand_gen->rand(0, 100);

    if(isset($num[$rand])) $num[$rand] += 1;
    else $num[$rand] = 1;
}
arsort($num);

foreach($num as $key=>$val){
    echo "The number $key has occured $val times.<br/>";
}?>

PHP Code:
<?php $rand_gen = new irand;
$rand = $rand_gen->rand(0, 100);?>

PHP Code:
<?php
class irand{
    private static $arr = array(NULL); //Holds the information of already generated numbers


/*
* Outputs the number.
*/
    public function rand($min = 0, $max = FALSE, $seed = false){
        if($seed) mt_srand($seed);

        if(!$max) $max = mt_getrandmax(); //If it isn't set.

        $return = $this->generate(mt_rand($min, $max), $min, $max);
        if(!$return && !is_numeric($return)){ //Everything was tested. Start again.
            self::$arr = array(NULL);
            return $this->generate(mt_rand($min, $max), $min, $max);
        }

        return $return;

    }
/*
* Checks if a the variable was generated already.
*/
    private function exists($num){
        foreach(self::$arr as $val){
            if($val == $num) return TRUE; //Tests if the number was already generated
        }
        return FALSE;
    }

/*
* Generates the number.
*/
    private function generate($rand, $min, $max){
        if (empty(self::$arr[0]) && !is_numeric(self::$arr[0])){
            self::$arr[0] = mt_rand($min, $max);
            return self::$arr[0];
        }

        while($this->exists($rand)){
            if(count(self::$arr) == (($max - $min) +1)) return FALSE;
            $rand = mt_rand($min, $max);
        }
        self::$arr[] = $rand;
        return $rand;
    }
}

?>

example code:

PHP Code:
<?php require_once 'object.php';

$rand_gen = new irand;


$num = array();
for($temp = 0; $temp <= 100; $temp++){
    $rand = $rand_gen->rand(0, 100);

    if(isset($num[$rand])) $num[$rand] += 1;
    else $num[$rand] = 1;
}
arsort($num);

foreach($num as $key=>$val){
    echo "The number $key has occured $val times.<br/>";
}?>

RE: [source]Custom random number generator - Madderc - 05-09-2013

Good going 1llusion, I might try to help you one day but my skills might not be at that level yet, I mean, I had some troubles with random numbers myself Biggrin

if I put 10 numbers and randomly select 3 of them, I would get results like 3, 7, 3 Biggrin

RE: [source]Custom random number generator - 1llusion - 05-09-2013

I believe I have fixed the bug with numbers repeating themselves.
If you find any bugs, please report so I can update the script Smile

Thank you