Difference

Description

This operation computes the difference between two FSAs. Any string in the second automaton is removed from the first automaton.

The first argument must be an acceptor; the second argument must be an unweighted, epsilon-free, deterministic acceptor. The output labels of the first acceptor or the input labels of the second acceptor must be sorted.

Usage

template <class Arc> void Difference(const Fst<Arc> &ifsa1, const Fst<Arc> &ifsa2, MutableFst<Arc> *ofsa);	[bad link?]
template <class Arc> DifferenceFst<Arc>:: DifferenceFst(const Fst<Arc> &fsa1, const Fst<Arc> &fsa2);
fstdifference [--opts] a.fsa b.fsa out.fsa --connect: Trim output (def: true)

Examples

A:

B:

A - B:

Difference(A, B, &C);
DifferenceFst<Arc>(A, B);
fstdifference a.fsa b.fsa out.fsa

Complexity

Same as Compose.

Caveats

Same as Compose.

-- MichaelRiley - 30 Jun 2007