Index Set

In mathematics, the elements of a set A may be indexed or labeled by means of a set J that is on that account called an index set. The indexing consists of a surjective function from J onto A and the indexed collection is typically called an (indexed) family, often written as (Aj)jJ.

In computational complexity theory and cryptography, an index set is a set for which there exists an algorithm I that can sample the set efficiently; i.e., on input 1n, I can efficiently select a poly(n)-bit long element from the set.

Read more about Index Set:  Examples

Famous quotes containing the words index and/or set:

    Exile as a mode of genius no longer exists; in place of Joyce we have the fragments of work appearing in Index on Censorship.
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