Creating and saving an Attribute-Relation File Format (ARFF) file
Weka's native file format is called Attribute-Relation File Format (ARFF). There are two logical parts of an ARFF file. The first part is called header, and the second part is called data . The header part has three physical sections that must be present in an ARFF file--the name of the relation, the attributes or features, and their data types and ranges. The data part has one physical section that must also be present to generate a machine-learning model. The header part of an ARFF file looks like the following:
% 1. Title: Iris Plants Database
%
% 2. Sources:
% (a) Creator: R.A. Fisher
% (b) Donor: Michael Marshall (MARSHALL%PLU@io.arc.nasa.gov)
% (c) Date: July, 1988
%
@RELATION iris
@ATTRIBUTE sepallength NUMERIC
@ATTRIBUTE sepalwidth NUMERIC
@ATTRIBUTE petallength NUMERIC
@ATTRIBUTE petalwidth NUMERIC
@ATTRIBUTE class {Iris-setosa...
