sfstlib.h

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// Copyright 2018-2024 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the 'License');
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an 'AS IS' BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// See sfst.opengrm.org for documentation of this library for
// stochastic finite-state transducers.

// SFst is a library for normalizing, sampling, combining, and
// approximating stochastic (or probabilistic) finite-state
// transducers. These are weighted finite-state transducers,
// represented in OpenFst library format, that have the following two
// properties:
//
// 1. normalized: the paths into the future from each state sum to
// Weight::One().
//
// 2. canonical topology:
//   * the states are sorted by input label
//   * there may be failure transitions (see phi-labeled transitions) but
//      * there is at most one such transition per state
//      * there are no failure-transition (and/or epsilon-transition) cycles
//   * no assumption is made of general determinism or what transitions must be
//     present on failure (unlike in a canonical n-gram model).
//
//
// For example, an n-gram model produced by the OpenGrm NGram Library
// is a stochastic FST (provided the phi_label is specified to match
// the backoff label, typically 0, of the n-gram model), but many
// other topologies are possible.
//
// If the input automaton is a transducer, then unless otherwise
// stated, the algorithms here only examine the input labels.
//
// Computation is done internally with Log64Weight (or sometimes
// SignedLog64Weight). Conversion from the input weight type is done
// using a fst::WeightConvert functor, pre-defined for common
// weight types like TropicalWeight and LogWeight.

// This convenience file includes all other SFST header files.

#ifndef NLP_GRM2_SFST_SFSTLIB_H_
#define NLP_GRM2_SFST_SFSTLIB_H_

#include <sfst/equal.h>
#include <sfst/sfst.h>

#endif  // NLP_GRM2_SFST_SFSTLIB_H_