acos() 是MySQL 的数学函数。该函数用于获取给定数字的反余弦值。
语法
select acos(num);
参数:
num:取反余弦的数。
返回
此函数返回数字的反余弦值。
示例 1
Select acos(0.23654);
输出:
mysql> Select acos(0.23654);
+-------------------+
| acos(0.23654) |
+-------------------+
| 1.331993084784758 |
+-------------------+
1 row in set (0.00 sec)
示例 2
Select acos(23654);
输出:
mysql> Select acos(23654);
+-------------+
| acos(23654) |
+-------------+
| NULL |
+-------------+
1 row in set (0.00 sec)
示例 3
Select acos(23654.21);
输出:
mysql> Select acos(23654.21);
+----------------+
| acos(23654.21) |
+----------------+
| NULL |
+----------------+
1 row in set (0.00 sec)
示例 4
Select acos(-23654);
输出:
mysql> Select acos(-23654);
+--------------+
| acos(-23654) |
+--------------+
| NULL |
+--------------+
1 row in set (0.00 sec)