根据用户定义的权重选择随机元素

我在几个PHP游戏引擎中使用了此功能：

<?phpfunction getBucketFromWeights($values) {    $total = $currentTotal = $bucket = 0;    $firstRand = mt_rand(1, 100);    foreach ($values as $amount) {        $total += $amount;    }    $rand = ($firstRand / 100) * $total;    foreach ($values as $amount) {        $currentTotal += $amount;        if ($rand > $currentTotal) { $bucket++;        }        else { break;        }    }    return $bucket;}

用法

假设我在一个关联数组中具有用户权重，其中每个字符串都指向其权重：

$weighted_strings = array(    "important string" => 100,    "terrible string" => 10,    "never string" => 0,    // etc);

如果我想根据重量拉一根绳子，可以这样做：

$weights = array_values($weighted_strings);$strings = array_keys($weighted_strings);$index = getBucketFromWeights($weights);$selectedString = $strings[$index];