function rateConfig()
{
return [
1 => 0.397,
2 => 0.400,
3 => 0.203,
];
}

function randRate()
{
$rateConfig = rateConfig();
foreach ($rateConfig as $k => $v) {
$rateConfig[$k] = $v * 10000;
}

//概率数组的总概率精度
$proSum = array_sum($rateConfig);

//概率数组循环
foreach ($rateConfig as $key => $proCur) {
$randNum = mt_rand(1, $proSum);
if ($randNum <= $proCur) { $result = $key; break; } else { $proSum -= $proCur; } } unset ($proArr); return $result; }