$num = 10.4567;
### 第一种:利用round()对浮点数进行四舍五入
```
echo round($num,2); //10.46
```
### 第二种:利用sprintf格式化字符串
```
$format_num = sprintf("%.2f",$num);
echo $format_num; //10.46
```
### 第三种:利用千位分组来格式化数字的函数number_format()
```
echo number_format($num, 2); //10.46
```
#### 或者如下
```
echo number_format($num, 2, '.', ''); //10/46
```