Let A be a large exampleset, without an id attribute.
Let B be a smaller exampleset with the same set of attributes, but fewer examples, say N.
(Usually N < 5)
Suppose we know that B is equal to some contiguous subrange of the examples in A. In other words, there exists some integer K such that every attribute in example B == every attribute in example A[K+J] for all J from 1 to N.
How can I get K? (e.g. into a macro)
