COS
描述
计算参数的余弦值
语法
COS(<a>)
参数
参数 | 说明 |
---|---|
<a> | 浮点数,要计算参数的弧度值 |
返回值
参数 <a>
的余弦值,弧度制表示。
特殊情况
- 当
a
为NaN
,返回NaN
- 当
a
为正无穷或负无穷(±Infinity
),返回NaN
- 当
a
为NULL
,返回NULL
举例
select cos(1);
+---------------------+
| cos(1.0) |
+---------------------+
| 0.54030230586813977 |
+---------------------+
select cos(0);
+------------------------+
| cos(cast(0 as DOUBLE)) |
+------------------------+
| 1.0 |
+------------------------+
select cos(Pi());
+-----------+
| cos(pi()) |
+-----------+
| -1 |
+-----------+
select cos(cast('nan' as double));
+----------------------------+
| cos(cast('nan' AS DOUBLE)) |
+----------------------------+
| NaN |
+----------------------------+
select cos(cast('inf' as double));
+----------------------------+
| cos(cast('inf' AS DOUBLE)) |
+----------------------------+
| NaN |
+----------------------------+
select cos(cast('-inf' as double));
+-----------------------------+
| cos(cast('-inf' AS DOUBLE)) |
+-----------------------------+
| NaN |
+-----------------------------+