Java Doc for Attribute.java in  » Science » weka » weka » core » Java Source Code / Java DocumentationJava Source Code and Java Documentation

The following attribute types are supported:

• numeric:
  This type of attribute represents a floating-point number.
• nominal:
  This type of attribute represents a fixed set of nominal values.
• string:
  This type of attribute represents a dynamically expanding set of nominal values. Usually used in text classification.
• date:
  This type of attribute represents a date, internally represented as floating-point number storing the milliseconds since January 1, 1970, 00:00:00 GMT. The string representation of the date must be ISO-8601 compliant, the default is yyyy-MM-dd'T'HH:mm:ss.
• relational:
  This type of attribute can contain other attributes and is, e.g., used for representing Multi-Instance data. (Multi-Instance data consists of a nominal attribute containing the bag-id, then a relational attribute with all the attributes of the bag, and finally the class attribute.)

...
// Create numeric attributes "length" and "weight"
Attribute length = new Attribute("length");
Attribute weight = new Attribute("weight");

// Create vector to hold nominal values "first", "second", "third"
FastVector my_nominal_values = new FastVector(3);
my_nominal_values.addElement("first");
my_nominal_values.addElement("second");
my_nominal_values.addElement("third");

// Create nominal attribute "position"
Attribute position = new Attribute("position", my_nominal_values);
...


author:
   Eibe Frank (eibe@cs.waikato.ac.nz)
version:
   $Revision: 1.44 $