# Log function

Returns a **Double** specifying the natural logarithm of a number.

## Syntax

**Log**(*number*)

The required *number* argument is a Double or any valid numeric expression greater than zero.

## Remarks

The natural logarithm is the logarithm to the base *e*. The constant *e* 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:

Log*n(x)* = **Log**(*x*) / **Log**(*n*)

The following example illustrates a custom **Function** that calculates base-10 logarithms:

```
Static Function Log10(X)
Log10 = Log(X) / Log(10#)
End Function
```

## Example

This example uses the **Log** function to return the natural logarithm of a number.

```
Dim MyAngle, MyLog
' Define angle in radians.
MyAngle = 1.3
' Calculate inverse hyperbolic sine.
MyLog = Log(MyAngle + Sqr(MyAngle * MyAngle + 1))
```

## See also

### Support and feedback

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