# LN or LOG macro

The `LN` or `LOG` macro is available only in Unica Campaign.

## Syntax

`LN(data)` or `LOG(data)`

## Parameters

`data`

The numerical values to compute the natural logarithm of. This can be a constant value, a column, a cell range, or an expression evaluating to any of the above. For the format definition of `data`, see the "Macro Function Parameters" section in the chapter in this guide for your product.

## Description

`LN` or `LOG` calculates the natural log of each value in the specified data range. It returns one new column for each input column, each containing the natural logarithm of numbers in the corresponding input column. Natural logarithms are based on the constant e = 2.7182818. `LN` is the inverse of the `EXP` macro function.

Note: All values in the specified data range must be greater than zero. Otherwise, a blank cell is returned for each invalid input.

## Examples

 `TEMP = LN(3)` or `TEMP = LOG(3)` Creates a new column named `TEMP` containing the value `1.099`. `TEMP = LN(V1)` Creates a new column named `TEMP`, where each value is the natural log of the contents of column `V1`. `TEMP = LN(V1:V3)` Creates three new columns named `TEMP`, `VX`, and `VY`. The values in the `TEMP` column are the natural logs of the contents of column `V1`, the values in the `VX` column are the natural logs of the contents of column `V2`, and the values in the `VY` column are the natural logs of the contents of column `V3`. `TEMP = LN(V1[10:20])` Creates a new column named `TEMP`, where the first 11 cells contain the natural logs of the values in rows 10-20 of column `V1`. The other cells in `TEMP` are empty. `TEMP = LN(V1[1:5]:V2)` Creates two new columns named `TEMP` and `VX`, each with values in rows 1-5 (the other cells are empty). The values in column `TEMP` are the natural logs of the corresponding rows of column `V1`, and the values in column `VX` are the natural logs of the corresponding rows of column `V2`.

## Related functions

Function Description
`EXP` Computes the natural number (e) raised to the contents of each cell in the specified data range
`LOG2` Computes the log base2 of the contents of the specified data range
`LOG10` Computes the log base10 of the contents of the specified data range
`POW` Computes a base value raised to the specified exponential power(s)