The following node is available in the Open Source KNIME predictive analytics and data mining platform version 2.7.1. Discover over 1000 other nodes, as well as enterprise functionality at http://knime.com.

Math Formula

This node evaluates a (free-form) mathematical expression based on the values in a row. The computed results can be either appended as new column or be used to replace an input column. Available variables are the values in the corresponding row of the table (left list in the dialog). Commonly used functions are shown in the list "Mathematical Functions". There are also some constants available, such as pi (the ratio of the circumference of a circle to its diameter),e (the base of the natural logarithms), the total number of rows in the table, and some other column based constants (right list).

This node uses JEP, the Java Math Expression Parser.

Dialog Options

Column List
Available numerical input columns. Click any column name (or constant, e.g. the row number) to include the value in the expression text field.
Mathematical Function
Mathematical functions that can be used, the tooltip shows a short description for each function.
Constants
Constant values available during execution. Column based constants such as COL_MIN(col_name) will be calculated in advance (if necessary).

Ports

Input Ports
0 Any input data
Output Ports
0 Input data amended with math column.
This node is contained in KNIME Math Expression Node provided by KNIME GmbH, Konstanz, Germany.