# LN Function

Computes the natural logarithm of an input value. The value can be a Decimal or Integer literal or a reference to a column containing numeric values.
• The natural logarithm of a value is the value of e x such that is the input value.

Wrangle vs. SQL: This function is part of Wrangle, a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.

## Basic Usage

Numeric literal example:

`ln(10)`

Output: Returns the value X, such that e x, is 10. This value is approximately `2.302585092994046`.

Column reference example:

`ln(MyValue)`

Output: Returns the power to which e is raised to yield the value in the `MyValue` column.

## Syntax and Arguments

`ln(numeric_value)`

ArgumentRequired?Data TypeDescription
numeric_valueYstring, decimal, or integerName of column or Decimal or Integer literal to apply to the function

### numeric_value

Name of the column or numeric literal, the natural logarithm of which is to be computed.

• Missing input values generate missing results.
• Literal numeric values should not be quoted. Quoted values are treated as strings.
• Multiple columns and wildcards are not supported.

Usage Notes:

Required?Data TypeExample Value
YesString (column reference) or Integer or Decimal literal`10`

## Examples

Tip: For additional examples, see How-to Guides.

### Example - Exponential Functions

The following example demonstrates how the exponential functions work together. These functions include the following:

Source:

rowNumX
1-2
21
30
41
52
63
74
85

Transformation:

Transformation Name `New formula` `Single row formula` `EXP (X)` `'expX'`

Transformation Name `New formula` `Single row formula` `LN (expX)` `'ln_expX'`

Transformation Name `New formula` `Single row formula` `LOG (X)` `'logX'`

Transformation Name `New formula` `Single row formula` `POW (10,logX)` `'pow_logX'`

Results:

In the following, `(null value)` indicates that a null value is generated for the computation.

rowNumXexpXln_expXlogXpow_logX
1-20.1353352832366127-2(null value)(null value)
2-10.1353352832366127-0.9999999999999998(null value)(null value)
3010(null value)0
412.718281828459045101
527.389056098930649520.301029995663981141.9999999999999998
6320.08553692318766830.477121254719662443
7454.5981500331442340.60205999132796233.999999999999999
85148.4131591025765750.69897000433601874.999999999999999