This function is used to return the arc cosine value of a given angle a.
Syntax
acos(DOUBLE a)
Parameters
Parameter |
Mandatory |
Type |
Description |
|---|---|---|---|
a |
Yes |
DOUBLE, BIGINT, DECIMAL, or STRING |
The value range is [-1,1]. The value can be a float, integer, or string. If the value is not of the DOUBLE type, the system will implicitly convert it to the DOUBLE type for calculation. |
Return Values
The return value is of the DOUBLE type. The value ranges from 0 to π.
- If the value of a is not within the range [-1,1], NaN is returned.
- If the value of a is NULL, NULL is returned.
Example Code
The value 3.141592653589793 is returned.
select acos(-1);
The value 0 is returned.
select acos(1);
The value NULL is returned.
select acos(null);
The value NAN is returned.
select acos(10);