一、方法一
function get_rand($proArr) {
$result = array();
foreach ($proArr as $key => $val) {
$arr[$key] = $val['v'];
}
// 概率数组的总概率
$proSum = array_sum($arr);
asort($arr);
// 概率数组循环
foreach ($arr as $k => $v) {
$randNum = mt_rand(1, $proSum);
if ($randNum <= $v) {
$result = $proArr[$k];
break;
} else {
$proSum -= $v;
}
}
return $result;
}
$arr = array(
array('id'=>1,'name'=>'特等奖','v'=>1),
array('id'=>2,'name'=>'一等奖','v'=>5),
array('id'=>3,'name'=>'二等奖','v'=>10),
array('id'=>4,'name'=>'三等奖','v'=>12),
array('id'=>5,'name'=>'四等奖','v'=>22),
array('id'=>6,'name'=>'没中奖','v'=>50)
);
var_dump(get_rand($arr));
二、方法二
function get_rand($proArr) {
$result = '';
//概率数组的总概率精度
$proSum = array_sum($proArr);
//概率数组循环
foreach ($proArr as $key => $proCur) {
$randNum = mt_rand(1, $proSum);
if ($randNum <= $proCur) {
$result = $key;
break;
} else {
$proSum -= $proCur;
}
}
unset($proArr);
return $result;
}
$arr = array(
array('id'=>1,'name'=>'特等奖','v'=>1),
array('id'=>2,'name'=>'一等奖','v'=>5),
array('id'=>3,'name'=>'二等奖','v'=>10),
array('id'=>4,'name'=>'三等奖','v'=>12),
array('id'=>5,'name'=>'四等奖','v'=>22),
array('id'=>6,'name'=>'没中奖','v'=>50)
);
foreach ($arr as $val) {
$item[$val['id']] = $val['v'];
}
var_dump(get_rand($item));
