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            long start = System.currentTimeMillis();
            hmmManager.setGpsList(gpslist);
            List<Foot_Data> list = hmmManager.GetLocations();
            long end = System.currentTimeMillis();
            Log.e("HMM TIME COST", String.valueOf(end - start));

public List<Foot_Data> GetLocations() {
    setUpClass();
    ViterbiAlgorithm<RoadPosition, GpsMeasurement, RoadPath> viterbi =
            new ViterbiAlgorithm<>();
    TimeStep<RoadPosition, GpsMeasurement, RoadPath> prevTimeStep = null;
    for (GpsMeasurement gpsMeasurement : gpsList) {
        final Collection<RoadPosition> candidates = computeCandidates(gpsMeasurement);
        final TimeStep<RoadPosition, GpsMeasurement, RoadPath> timeStep =
                new TimeStep<>(gpsMeasurement, candidates);
        computeEmissionProbabilities(timeStep);
        if (prevTimeStep == null) {
            viterbi.startWithInitialObservation(timeStep.observation, timeStep.candidates,
                    timeStep.emissionLogProbabilities);
        } else {
            computeTransitionProbabilities(prevTimeStep, timeStep);
            viterbi.nextStep(timeStep.observation, timeStep.candidates,
                    timeStep.emissionLogProbabilities, timeStep.transitionLogProbabilities,
                    timeStep.roadPaths);
        }
        prevTimeStep = timeStep;
    }
    List<Foot_Data> list = new ArrayList<>();
    List<SequenceState<RoadPosition, GpsMeasurement, RoadPath>> roadPositions =
            viterbi.computeMostLikelySequence();
    for (SequenceState<RoadPosition, GpsMeasurement, RoadPath> s : roadPositions){
        Point p = s.state.position;
        Road_Data road_data = s.state.road_data;
        list.add(new Foot_Data(p,road_data));
    }
    return list;
}