AddExpression
Package
weka.filters.unsupervised.attribute
Synopsis
An instance filter that creates a new attribute by applying a mathematical expression to existing attributes. The expression can contain attribute references and numeric constants. Supported operators are :
+, -, *, /, ^, log, abs, cos, exp, sqrt, floor, ceil, rint, tan, sin, (, )
Attributes are specified by prefixing with 'a', eg. a7 is attribute number 7 (starting from 1).
Example expression : a1^2*a5/log(a7*4.0).
Options
The table below describes the options available for AddExpression.
Option |
Description |
|---|---|
debug |
Set debug mode. If true then the new attribute will be named with the postfix parse of the supplied expression. |
expression |
Set the math expression to apply. Eg. a1^2*a5/log(a7*4.0) |
name |
Set the name of the new attribute. |
Capabilities
The table below describes the capabilites of AddExpression.
Capability |
Supported |
|---|---|
Class |
Unary class, Nominal class, Missing class values, Empty nominal class, Binary class, Date class, Numeric class, String class, No class, Relational class |
Attributes |
Relational attributes, Empty nominal attributes, Date attributes, Numeric attributes, Unary attributes, String attributes, Nominal attributes, Binary attributes, Missing values |
Min # of instances |
0 |