TANH

描述

返回 x 的双曲正切值。

语法

TANH(<x>)

参数

参数	说明
<x>	需要被计算双曲正切值

返回值

参数 x 的双曲正切值。

特殊情况

• 当 x 为 NaN，返回 NaN
• 当 x 为正无穷，返回 1
• 当 x 为负无穷，返回 -1
• 当 x 为 NULL，返回 NULL

举例

select tanh(0),tanh(1);

+-------------------------+-------------------------+
| tanh(cast(0 as DOUBLE)) | tanh(cast(1 as DOUBLE)) |
+-------------------------+-------------------------+
|                       0 |      0.7615941559557649 |
+-------------------------+-------------------------+

select tanh(cast('nan' as double));

+----------------------------+
| tanh(cast('nan' AS DOUBLE))|
+----------------------------+
| NaN                        |
+----------------------------+

select tanh(cast('inf' as double));

+----------------------------+
| tanh(cast('inf' AS DOUBLE))|
+----------------------------+
| 1                          |
+----------------------------+

select tanh(cast('-inf' as double));

+-----------------------------+
| tanh(cast('-inf' AS DOUBLE))|
+-----------------------------+
| -1                          |
+-----------------------------+