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.
