Mgccl's blogI'm the standard deviAsian.

<?php
/*********************************
RandomLib Version 1.3
Programmed by : Chao Xu(Mgccl)
E-mail        : mgcclx@gmail.com
Website       : http://mgccl.com
Info          : Please email me if there is any feature you want
or there is any bugs. I will fix them as soon as possible.
Change        :
1.3
Add the rand() method, it choses which random method to be used
on generate random numbers.
1.2
Add truerand(), get a random number from http://www.random.org
1.1
Add some BC functions and the power of generate
very large random numbers
ToDo         :Optimize BCrand speed, chose the random handler
*********************************/
 
class random{
var $data = array();
var $rand_op = 'rand';
 
function rand($min = 0, $max = 1, $amount = 1){
	if($this->rand_op=='rand'){
		if($amount == 1){
			return rand($min, $max);
		}else{
			$i = 0;
			while($i< $amount){
				$rand[] =rand($min, $max);
				++$i;
			}
			return $rand;
		}
	}elseif($this->rand_op=='mt_rand'){
		if($amount == 1){
			return mt_rand($min, $max);
		}else{
			$i = 0;
			while($i< $amount){
				$rand[] =mt_rand($min, $max);
				++$i;
			}
			return $rand;
		}
	}elseif($this->rand_op=='truerand'){
		return $this->truerand($min, $max, $amount);
	}
}
function add($string,$weight=1){
    $this->data[] = array('s' => $string, 'w' => $weight);
}
function optimize(){
    foreach($this->data as $var){
        if($new[$var['s']]){
            $new[$var['s']] += $var['w'];
        }else{
            $new[$var['s']] = $var['w'];
        }
    }
    unset($this->data);
    foreach($new as $key=>$var){
        $this->data[] = array('s' => $key, 'w' => $var);
    }
}
 
function select($amount=1){
    if($amount == 1){
        $rand = array_rand($this->data);
        $result = $this->data[$rand]['s'];
    }else{
        $i = 0;
        while($i<$amount){
            $result[] = $this->data[array_rand($this->data)]['s'];
            ++$i;
        }
    }
    return $result;
}
 
function select_unique($amount=1){
    if($amount == 1){
        $rand = array_rand($this->data);
        $result = $this->data[$rand]['s'];
    }else{
        $rand = array_rand($this->data, $amount);
        foreach($rand as $var){
            $result[] = $this->data[$var]['s'];
        }
    }
    return $result;
}
 
function select_weighted($amount=1){
    $count = count($this->data);
    $i = 0;
    $max = -1;
    while($i < $count){
        $max += $this->data[$i]['w'];
        ++$i;
    }
    if(1 == $amount){
        $rand = $this->rand(0, $max);
        $w = 0; $n = 0;
        while($w <= $rand){
            $w += $this->data[$n]['w'];
            ++$n;
        }
        $key = $this->data[$n-1]['s'];
    }else{
        $i = 0;
        while($i<$amount){
            $random[] = $this->rand(0, $max);
            ++$i;
        }
        sort($random);
        $i = 0;
        $n = 0;
        $w = 0;
        while($i<$amount){
            while($w<=$random[$i]){
                $w += $this->data[$n]['w'];
                ++$n;
            }
            $key[] = $this->data[$n-1]['s'];
            ++$i;
        }
    }
    return $key;
}
 
function bc_select_weighted($amount=1){
    $count = count($this->data);
    $i = 0;
    $max = -1;
    while($i < $count){
        $max = bcadd($this->data[$i]['w'],$max);
        ++$i;
    }
    if(1 == $amount){
        $rand = $this->bcrand(0, $max);
        $w = 0; $n = 0;
        while(bccomp($w,$rand) == 0||bccomp($w,$rand)== -1){
            $w = bcadd($this->data[$n]['w'],$w);
            ++$n;
        }
        $key = $this->data[$n-1]['s'];
    }else{
        $i = 0;
        while($i<$amount){
            $random[] = $this->bcrand(0, $max);
            ++$i;
        }
        natsort($random);
        $i = 0;
        $n = 0;
        $w = 0;
        while($i<$amount){
            while(bccomp($w,$random[$i]) == 0||bccomp($w,$random[$i])== -1){
                $w = bcadd($this->data[$n]['w'],$w);
                ++$n;
            }
            $key[] = $this->data[$n-1]['s'];
            ++$i;
        }
    }
    return $key;
}
 
 
 
function select_weighted_unique($amount=1){
	if($amount == 1){
		return $this->select_weighted(1);
	}
    $count = count($this->data);
    $i = 0;
    if($amount >= $count){
        while($i < $count){
            $return[] = $this->data[$i]['s'];
            ++$i;
        }
        return $return;
    }else{
        $max = -1;
        while($i < $count){
            $max += $this->data[$i]['w'];
            ++$i;
        }
 
        $i = 0;
        while($i < $amount){
            $max -= $sub;
            $w = 0;
            $n = 0;
            $num = $this->rand(0,$max);
            while($w <= $num){
                $w += $this->data[$n]['w'];
                ++$n;
            }
            $sub = $this->data[$n-1]['w'];
            $key[] = $this->data[$n-1]['s'];
 
            array_splice($this->data, $n-1, 1);
            ++$i;
        }
        return $key;
    }
}
 
function bc_select_weighted_unique($amount=1){
	if($amount == 1){
		return $this->bc_select_weighted(1);
	}
    $count = count($this->data);
    $i = 0;
    if($amount >= $count){
        while($i < $count){
            $return[] = $this->data[$i]['s'];
            ++$i;
        }
        return $return;
    }else{
        $max = -1;
        while($i < $count){
            $max = bcadd($this->data[$i]['w'],$max);
            ++$i;
        }
 
        $i = 0;
        while($i < $amount){
            $max = bcsub($max,$sub);
            $w = 0;
            $n = 0;
            $num = $this->bcrand(0,$max);
            //BCCOMP!!!!!!
            while(bccomp($w,$num) == 0 || bccomp($w,$num) == -1){
                $w = bcadd($this->data[$n]['w'],$w);
                ++$n;
            }
            $sub = $this->data[$n-1]['w'];
            $key[] = $this->data[$n-1]['s'];
 
            array_splice($this->data, $n-1, 1);
            ++$i;
        }
        return $key;
    }
}
 
function bcrand($min, $max){
	bcscale(0);
	if(bccomp($max,$min)!=1){
		return 0;
	}
	$top = bcsub($max,$min);
	$rand = bcadd($top, 1);
	$length = strlen($top);
 
		$n = 0;
		while(9*$n <= $length){
			if($length - 9*$n >= 9){
				$rand_part[] = $this->rand(0,999999999);
			}else{
				$j = 0; $foo = '';
				while($j < $length-9*$n){
					$foo .= '9';
					++$j;
				}
				$foo += 0;
				$rand_part[] = $this->rand(0,$foo);
			}
			++$n;
		}
		$i = 0;
		$rand ='';
		$count = count($rand_part);
		while($i < $count){
			$rand .= $rand_part[$i];
			++$i;
		}
	while(bccomp($rand,$top)==1){
		$rand = substr($rand,1,strlen($rand)).$this->rand(0,9);
	}
	return bcadd($rand,$min);
}
 
function truerand($min, $max, $amount=1){
	if($amount == 1){
		$fp = fopen("http://www.random.org/cgi-bin/randnum?num="
.$amount."&min="."$min"."&max="."$max"."&col=1", "r");
		$num = fread($fp, 4096*$amount);
		fclose($fp);
		return $num;
	}else{
		if($amount > 10000){
			return false;
		}
		$fp = fopen("http://www.random.org/cgi-bin/randnum?num="
.$amount."&min="."$min"."&max="."$max"."&col=1", "r");
		$num = fread($fp, 4096*$amount);
		fclose($fp);
		$num = explode("\n", $num);
		unset($num[count($num)-1]);
		return $num;
	}
}
 
}
?>