Accession Number:
AD0697040
Title:
TWO CHARACTERISTIZATIONS OF THE CONTEXT-SENSITIVE LANGUAGES,
Descriptive Note:
Corporate Author:
CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF COMPUTER SCIENCE
Personal Author(s):
Report Date:
1969-09-01
Pagination or Media Count:
15.0
Abstract:
An n-dimensional bug-automation is a generalization of a finite state acceptor to n-dimensions. With each bug B, is associated the language LB which is the set of top rows of n-dimensional rectangular arrays accepted by B. One-dimensional bugs define trivially the regular sets. Two-dimensional bugs define precisely the context-sensitive languages, while bugs of dimension 3 or greater define all the recursively enumerable sets. Finite state acceptors with n two-way non-writing input tapes are also considered. For each such machine M, let domain M be the set of all strings which are the first component of some n-tuple of tapes accepted by M. For any n or 1, the domains of n-tape finite state acceptors are precisely the same as the languages definable by n-dimensional bugs, so as a corollary, the domains of two-tape two-way finite state acceptors are precisely the contest-sensitive languages. Author
Descriptors:
Subject Categories:
- Linguistics
- Computer Programming and Software
- Bionics