Table of Contents

Search

  1. Preface
  2. The Transformation Language
  3. Constants
  4. Operators
  5. Dates
  6. Functions
  7. Creating Custom Functions
  8. Custom Function API Reference
  9. POWERCENTERHELP

Transformation Language Reference

Transformation Language Reference

LN

LN

Returns the natural logarithm of a numeric value. For example,
LN(3)
returns
1.098612
. You usually use this function to analyze scientific data rather than business data.
This function is the reciprocal of the function EXP.

Syntax

LN(
numeric_value
)
The following table describes the argument for this command:
Argument
Required/
Optional
Description
numeric_value
Required
Numeric datatype. It must be a positive number, greater than 0. Passes the values for which you want to calculate the natural logarithm. You can enter any valid transformation expression.

Return Value

Double value.
NULL if a value passed to the function is NULL.

Example

The following expression returns the natural logarithm for all values in the NUMBERS port:
LN( NUMBERS )
NUMBERS
RETURN VALUE
10
2.302585092994
125
4.828313737302
0.96
-0.04082199452026
NULL
NULL
-90
Error. (The Integration Service does not write row.)
0
Error. (The Integration Service does not write row.
)
The
PowerCenter Integration Service
displays an error and does not write the row when you pass a negative number or 0. The
numeric_value
must be a positive number greater than 0.