Variable patterns are much more difficult to define and handle.
Example applications for variable pattern set include TDNN patterns for one variable dimension and picture processing for two variable dimensions. The SNNS pattern definition is very flexible and allows a great degree of freedom. Unfortunately this also renders the writing of correct pattern files more difficult and promotes mistakes. To make the user acquainted with the pattern file format we describe the format with the help of an example pattern file. The beginning of the pattern file describing a bitmap picture is given below.