Chapter 9
Similarity Operations
ASPL similarity operator is a setadic operator that may be followed by one or many set variables. This operator invokes ASPL powerful similarity algorithm to process the data sets and summarize the similarity between them. When similarity or sim is invoked by itself without following it by any set variables, the command will do the operation on the last two elements on the answer stack. In addition, the command xsimilarity performs the same operation as similarity but an extended output is displayed following the execution of the command. Furthemore, the similarity operator is tickable with a predicate hence allowing you to perform similarity operations based on the elements attributes. Because similarity operator output is a stuctured data, knwon to ASPL as cosStruc data structure, the ASPL intepreter maintains a special symbol table (the COS symbol table) to hold the similarity variables. The command cos display the content of the COS symbol table. You can type help similarity at the ASPL prompt to print the help page of this command. The following chapter consists of pages describing ASPL Similarity Operator.
