Example usage for org.apache.lucene.queries.function.valuesource ReciprocalFloatFunction ReciprocalFloatFunction

Introduction

In this page you can find the example usage for org.apache.lucene.queries.function.valuesource ReciprocalFloatFunction ReciprocalFloatFunction.

Prototype

public ReciprocalFloatFunction(ValueSource source, float m, float a, float b) 

Source Link

Document

f(source) = a/(m*float(source)+b)

Usage

From source file:com.difference.historybook.index.lucene.LuceneIndex.java

License:Apache License

@Override
public SearchResultWrapper search(String collection, String query, int offset, int size, boolean includeDebug)
        throws IndexException {
    try {/*from   www.  j av  a 2  s  .c om*/
        //TODO: make age be a component in the ranking?
        BooleanQuery.Builder queryBuilder = new BooleanQuery.Builder();
        queryBuilder.add(parser.parse(query), Occur.MUST);
        queryBuilder.add(new TermQuery(new Term(IndexDocumentAdapter.FIELD_COLLECTION, collection)),
                Occur.FILTER);
        Query baseQuery = queryBuilder.build();

        FunctionQuery boostQuery = new FunctionQuery(
                new ReciprocalFloatFunction(new DurationValueSource(new Date().getTime() / 1000,
                        new LongFieldSource(IndexDocumentAdapter.FIELD_TIMESTAMP)), RECIP, 1F, 1F));

        Query q = new CustomScoreQuery(baseQuery, boostQuery);

        QueryScorer queryScorer = new QueryScorer(q, IndexDocumentAdapter.FIELD_SEARCH);
        Fragmenter fragmenter = new SimpleSpanFragmenter(queryScorer);
        Highlighter highlighter = new Highlighter(queryScorer);
        highlighter.setTextFragmenter(fragmenter);

        GroupingSearch gsearch = new GroupingSearch(IndexDocumentAdapter.FIELD_URL_GROUP).setGroupDocsLimit(1)
                .setAllGroups(true).setIncludeMaxScore(true);
        TopGroups<?> groups = gsearch.search(searcher, q, offset, size);

        ArrayList<SearchResult> results = new ArrayList<>(size);
        for (int i = offset; i < offset + size && i < groups.groups.length; i++) {
            ScoreDoc scoreDoc = groups.groups[i].scoreDocs[0];
            Document luceneDoc = searcher.doc(scoreDoc.doc);
            IndexDocumentAdapter doc = new IndexDocumentAdapter(luceneDoc);

            TokenStream tokenStream = TokenSources.getTokenStream(IndexDocumentAdapter.FIELD_SEARCH,
                    reader.getTermVectors(scoreDoc.doc), luceneDoc.get(IndexDocumentAdapter.FIELD_SEARCH),
                    analyzer, highlighter.getMaxDocCharsToAnalyze() - 1);

            String[] snippets = highlighter.getBestFragments(tokenStream,
                    luceneDoc.get(IndexDocumentAdapter.FIELD_SEARCH), 3);
            String snippet = Arrays.asList(snippets).stream().collect(Collectors.joining("\n"));
            snippet = Jsoup.clean(snippet, Whitelist.simpleText());

            String debugInfo = null;
            if (includeDebug) {
                Explanation explanation = searcher.explain(q, scoreDoc.doc);
                debugInfo = explanation.toString();
            }

            results.add(new SearchResult(doc.getKey(), doc.getCollection(), doc.getTitle(), doc.getUrl(),
                    doc.getDomain(), doc.getTimestampText(), snippet, debugInfo, scoreDoc.score));
        }

        SearchResultWrapper wrapper = new SearchResultWrapper().setQuery(query).setOffset(offset)
                .setMaxResultsRequested(size)
                .setResultCount(groups.totalGroupCount != null ? groups.totalGroupCount : 0)
                .setResults(results);

        if (includeDebug) {
            wrapper.setDebugInfo(q.toString());
        }

        return wrapper;

    } catch (IOException | ParseException | InvalidTokenOffsetsException e) {
        LOG.error(e.getLocalizedMessage());
        throw new IndexException(e);
    }
}

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From source file:org.apache.solr.search.function.distance.MultiPointDistanceValueSourceParser.java

License:Apache License

@Override
public ValueSource parse(FunctionQParser fp) throws SyntaxError {
    String fieldName = fp.parseId();
    SchemaField field = fp.getReq().getSchema().getField(fieldName);
    FieldType type = field.getType();/*w  w w.jav  a  2 s .  co  m*/
    if (!(type instanceof MultiPointDocValuesField))
        throw new SyntaxError("This function only supports fields of type "
                + MultiPointDocValuesField.class.getName() + ", not " + type.getClass().getName());
    MultiPointDocValuesField mpdvFieldType = (MultiPointDocValuesField) type;

    double[] parsedLatLong = null;
    try {
        parsedLatLong = ParseUtils.parseLatitudeLongitude(fp.parseArg());
    } catch (InvalidShapeException e) {
        throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e);
    }

    double y = parsedLatLong[0];
    double x = parsedLatLong[1];

    SpatialContext ctx = mpdvFieldType.getCtx();
    Point point = ctx.makePoint(x, y);

    String score = fp.getLocalParams().get("score", "distance");
    ValueSource valueSource = new MultiPointDistanceValueSource(fieldName, point, ctx);

    if ("distance".equals(score)) {
        return valueSource;
    } else if ("recipDistance".equals(score)) {
        int shift = fp.getLocalParams().getInt("shift", 100);
        int maxScore = fp.getLocalParams().getInt("maxScore", 10);
        return new ReciprocalFloatFunction(valueSource, maxScore, shift, shift);
    } else {
        throw new SolrException(SolrException.ErrorCode.BAD_REQUEST,
                "'score' local-param must be one of 'distance', or 'recipDistance'");
    }
}

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