ATAN - MaxCompute - 阿里雲

計算number的反正切函數。

命令格式

double atan(<number>)

參數說明

number：必填。DOUBLE類型。輸入為STRING、BIGINT、DECIMAL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類型。範圍在-π/2~π/2之間。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0.7853981633974483。
select atan(1);
--返回-0.7853981633974483。
select atan(-1);
--返回NULL。
select atan(null);

使用樣本：表資料樣本

基於樣本資料，計算反正切值，命令樣本如下。

select atan(bigint_data) as bigint_new, atan(double_data) as double_new, atan(decimal_data) as decimal_new, atan(string_data) as string_new from mf_math_fun_t;

返回結果如下。

+---------------------+----------------------+----------------------+---------------------+
| bigint_new          | double_new           | decimal_new          | string_new          |
+---------------------+----------------------+----------------------+---------------------+
| -1.4711276743037347 | 0.483447001567199    | 0.483447001567199    | 1.4711276743037347  |
| NULL                | -0.09966865249116204 | -0.09966865249116204 | -1.4711276743037347 |
| -0.7853981633974483 | NULL                 | 1.521935491607842    | 1.5374753309166493  |
| 1.3258176636680326  | 0.7272626879966904   | NULL                 | -1.5374753309166493 |
| -1.550798992821746  | -0.7853981633974483  | -0.7853981633974483  | 1.550798992821746   |
| 1.4056476493802699  | 0.982793723247329    | 0.982793723247329    | -1.550798992821746  |
| -1.5565115842075    | -1.4382447944982226  | -1.4382447944982226  | NULL                |
| 0.7853981633974483  | -1.473069419436178   | -1.473069419436178   | -0.7853981633974483 |
| -1.5596856728972892 | 1.2010277920014796   | 1.2010277920014796   | 0.0                 |
| 1.4711276743037347  | -1.4000611153196139  | -1.4000611153196139  | -1.5596856728972892 |
+---------------------+----------------------+----------------------+---------------------+

MaxCompute：ATAN