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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).


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.


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

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