計算number的雙曲正切函數。
命令格式
double|decimal tanh(<number>)
參數說明
number:必填。DOUBLE或DECIMAL類型。輸入為STRING、BIGINT類型時,會隱式轉換為DOUBLE類型後參與運算。
傳回值說明
返回DOUBLE或DECIMAL類型。返回規則如下:
number為DOUBLE、DECIMAL類型時會返回相應的類型。
number為STRING、BIGINT類型時,返回DOUBLE類型。
number值為NULL時,返回NULL。
樣本資料
為便於理解各函數的使用方法,本文為您提供來源資料,基於來源資料提供函數相關樣本。建立表mf_math_fun_t,並添加資料,命令樣本如下。
create table if not exists mf_math_fun_t(
int_data int,
bigint_data bigint,
double_data double,
decimal_data decimal,
float_data float,
string_data string
);
insert into mf_math_fun_t values
(null, -10, 0.525, 0.525BD, cast(0.525 as float), '10'),
(-20, null, -0.1, -0.1BD, cast(-0.1 as float), '-10'),
(0, -1, null, 20.45BD, cast(-1 as float), '30'),
(-40, 4, 0.89, null, cast(0.89 as float), '-30'),
(5, -50, -1, -1BD, null, '50'),
(-60, 6, 1.5, 1.5BD, cast(1.5 as float), '-50'),
(-1, -70, -7.5, -7.5BD, cast(-7.5 as float),null ),
(-80, 1, -10.2, -10.2BD, cast(-10.2 as float), '-1' ),
(9, -90, 2.58, 2.58BD, cast(2.58 as float), '0'),
(-100, 10, -5.8, -5.8BD, cast(-5.8 as float), '-90');
查詢表mf_math_fun_t中的資料,命令樣本如下:
select * from mf_math_fun_t;
--返回結果。
+------------+-------------+-------------+--------------+------------+-------------+
| int_data | bigint_data | double_data | decimal_data | float_data | string_data |
+------------+-------------+-------------+--------------+------------+-------------+
| NULL | -10 | 0.525 | 0.525 | 0.525 | 10 |
| -20 | NULL | -0.1 | -0.1 | -0.1 | -10 |
| 0 | -1 | NULL | 20.45 | -1.0 | 30 |
| -40 | 4 | 0.89 | NULL | 0.89 | -30 |
| 5 | -50 | -1.0 | -1 | NULL | 50 |
| -60 | 6 | 1.5 | 1.5 | 1.5 | -50 |
| -1 | -70 | -7.5 | -7.5 | -7.5 | NULL |
| -80 | 1 | -10.2 | -10.2 | -10.2 | -1 |
| 9 | -90 | 2.58 | 2.58 | 2.58 | 0 |
| -100 | 10 | -5.8 | -5.8 | -5.8 | -90 |
+------------+-------------+-------------+--------------+------------+-------------+
使用樣本:待用資料樣本
--返回1.0。
select tanh(30);
--返回NULL。
select tanh(null);
使用樣本:表資料樣本
基於樣本資料,計算資料行的雙曲正切值,命令樣本如下。
select tanh(bigint_data) as bigint_new, tanh(double_data) as double_new, tanh(decimal_data) as decimal_new, tanh(string_data) as string_new from mf_math_fun_t;
返回結果如下。
+---------------------+----------------------+----------------------+---------------------+
| bigint_new | double_new | decimal_new | string_new |
+---------------------+----------------------+----------------------+---------------------+
| -0.9999999958776927 | 0.48154979836430806 | 0.48154979836430806 | 0.9999999958776927 |
| NULL | -0.09966799462495582 | -0.09966799462495582 | -0.9999999958776927 |
| -0.7615941559557649 | NULL | 1.0 | 1.0 |
| 0.999329299739067 | 0.7113937318189625 | NULL | -1.0 |
| -1.0 | -0.7615941559557649 | -0.7615941559557649 | 1.0 |
| 0.9999877116507956 | 0.9051482536448664 | 0.9051482536448664 | -1.0 |
| -1.0 | -0.9999993881955461 | -0.9999993881955461 | NULL |
| 0.7615941559557649 | -0.9999999972367348 | -0.9999999972367348 | -0.7615941559557649 |
| -1.0 | 0.9885821584459533 | 0.9885821584459533 | 0.0 |
| 0.9999999958776927 | -0.9999816679925603 | -0.9999816679925603 | -1.0 |
+---------------------+----------------------+----------------------+---------------------+
相關函數
TANH函數屬於數學函數,更多資料計算、資料轉換的相關函數請參見數學函數。