# LN

Returns the natural logarithm of a number.

## Synopsis

LN(number)

### Arguments

number | An expression that resolves to a positive number. |

## Description

The LN function returns the natural logarithm of number. The number value must be a non-zero positive number; all other values generate an <ILLEGAL VALUE> error.

The LN function complements the action of the EXP function, which is sometimes referred to as the antilogarithm.

## Examples

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

FOR x=1 TO 10 PRINT "Natural log of ",x," = ",LN(x) NEXT

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## See Also

EXP function