/* * Copyright 2004 The Apache Software Foundation * * 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. */ using System; using TermPositions = Lucene.Net.Index.TermPositions; namespace Lucene.Net.Search { sealed class SloppyPhraseScorer:PhraseScorer { private int slop; internal SloppyPhraseScorer(Weight weight, TermPositions[] tps, int[] positions, Similarity similarity, int slop, byte[] norms) : base(weight, tps, positions, similarity, norms) { this.slop = slop; } protected internal override float PhraseFreq() { pq.Clear(); int end = 0; for (PhrasePositions pp = first; pp != null; pp = pp.next) { pp.FirstPosition(); if (pp.position > end) end = pp.position; pq.Put(pp); // build pq from list } float freq = 0.0f; bool done = false; do { PhrasePositions pp = (PhrasePositions) pq.Pop(); int start = pp.position; int next = ((PhrasePositions) pq.Top()).position; for (int pos = start; pos <= next; pos = pp.position) { start = pos; // advance pp to min window if (!pp.NextPosition()) { done = true; // ran out of a term -- done break; } } int matchLength = end - start; if (matchLength <= slop) freq += GetSimilarity().SloppyFreq(matchLength); // score match if (pp.position > end) end = pp.position; pq.Put(pp); // restore pq } while (!done); return freq; } } }