The LOG function returns the logarithm of a number to the base you specify.

This function is the inverse of the POWER function.

For example, if the formula POWER(a, b) gives a result of c, the formula LOG(c, a) gives a result of b.

## Syntax

LOG(Number, Base)

## Arguments

 Argument Data type Description Number Number The number to return the logarithm of. Base (optional) Number The base to apply when returning the logarithm. If omitted, the LOG function uses a default base of 10.

## Calculation engine functionality differences

In Polaris, the LOG function returns a value of NaN (Not a Number) if you use positive infinity for the Base argument.

In the Classic Engine, the LOG function returns 0 if you use positive infinity for the Base argument.

LOG

## Examples

### General examples

In this example, the Number and Base line items each contain four numeric values to be used for the Number and Base arguments respectively. The other two line items contain formulas to calculate the logarithm for the numbers.

As the formula for the Logarithm base 10 line item does not contain the Base argument, the function returns the base 10 logarithm by default.

The values in this example are rounded to eight significant digits. You can change the number of digits that display in Anaplan under Format in Blueprint.

 Item 1 Item 2 Item 3 Item 4 Number 14.25 234.56 35.00 456.78 Base 8 6 9 3 Logarithm with various bases LOG(Number, Base) 1.2776300 3.0460067 1.6181086 5.5744888 Logarithm base 10 LOG(Number) 1.1538149 2.3702540 1.5440680 2.6597071

Disclaimer

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