This function is used to return the natural logarithm of a given value.
Syntax
ln(DOUBLE a)
Parameters
Parameter |
Mandatory |
Type |
Description |
|---|---|---|---|
a |
Yes |
DOUBLE, BIGINT, DECIMAL, or STRING |
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.
- If the value of a is negative or 0, NULL is returned.
- If the value of a is NULL, NULL is returned.
Example Code
The value 1.144729868791239 is returned.
select ln(3.1415926);
The value 1 is returned.
select ln(2.718281828459045);
The value NULL is returned.
select ln(null);