SUBSINDEX  SUBSINDEX Overloaded Class Indexing


Usage
 
 This method is called for classes in the expressions
 of the form
 
   c = subsindex(a)
 
 where a is an object, and c is an index vector.
 It is also called for
 
   c = b(a)
 
 in which case subsindex(a) must return a vector containing
 integers between 0 and N-1 where N is the number
 of elements in the vector b.
 