# Log

Returns the natural logarithm of a number.

## Synopsis

```Log(number)
```

### Arguments

The number argument can be any valid numeric expression greater than 0. Specifying 0 or a negative number results in a runtime error.

## Description

The natural logarithm is the logarithm to the base e. The constant e (Exp(1)) is approximately 2.718282.

You can calculate base-n logarithms for any number x by dividing the natural logarithm of x by the natural logarithm of n as follows:

`Logn(x) = Log(x) / Log(n)`
Note:

In ObjectScript, the equivalent function is the \$ZLN function, which returns the natural logarithm. The \$ZLOG function returns the base-10 logarithm. Please note that Log and \$ZLOG are not equivalent functions.

## Examples

The following example uses the Log function to calculate the natural logarithm for each of the integers 1 through 10:

```For x = 1 To 10
Println "Natural log of ",x," = ",Log(x)
Next```

The following example uses the Log function to calculate the base-10 logarithms for the numbers 10 through 100, counting by tens. For 100, it returns 2 (10 to the power of x = 100).

```x = 10
For y = 1 To 10
Base10 = Log(x) / Log(10)
Println "Base-10 log of ",x," = ",Base10
x = x + 10
Next```