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L04 Towards Finite State Transducer Finite State Transducers (FST) o FST is like the finite state automation defined earlier, except each arc is labelled by a pair of symbols: i:o where i: symbol in input string o: symbol output by FST when are is taken + Ex. arc in finite state transducer corresponding to 'e' in 'ladake' e : ((+pl, -direct), (+sg, +dir)) q1 +----------------->--------------------+ q2 Two pairs of symbols: i : o - i is: 'e' - o is: '((+pl, -direct), (+sg, +dir))' + Ex. Morph Analyzer: Match input with i, if successful go ahead & produce o in output o Formally: Finite state transducer - Q: Finite set of states q0, ..., qN - SIGMA_IN: Finite set of input symbols - SIGMA_OUT: Finite set of pairs output symbols - q0: Start state (q0 IN Q) - F: Set of final accepting states (F SUBSET Q) - DELTA (q, i:o) : For every state q, gives a set of states that can be reached from q with i in SIGMA_IN, and o in SIGMA_OUT...........................................NEXT PREVIOUS INDEX