LN

Description

Returns the natural logarithm of x to base e.

Alias

• DLOG1

Syntax

LN(<x>)

Parameters

Parameter	Description
<x>	Antilogarithm should be greater than 0

Return value

Return a float-point number. Special cases:

• If x IS NULL, return NULL
• If x IS NaN, return NaN
• If x is positive infinity, return Infinity

Example

select ln(1);

+-----------------------+
| ln(cast(1 as DOUBLE)) |
+-----------------------+
|                   0.0 |
+-----------------------+

select ln(e());

+---------+
| ln(e()) |
+---------+
|     1.0 |
+---------+

select ln(10);

+------------------------+
| ln(cast(10 as DOUBLE)) |
+------------------------+
|      2.302585092994046 |
+------------------------+

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

+---------------------------+
| ln(cast('inf' as double)) |
+---------------------------+
|                  Infinity |
+---------------------------+

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

+---------------------------+
| ln(cast('nan' as double)) |
+---------------------------+
|                       NaN |
+---------------------------+