Java FastMath.logAdd方法代码示例

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
public void updateCell(int nt, double score, int mid, Rule r) {
    assert(!isClosed);
    if (bps[nt] == null) {
        // If the non-terminal hasn't been added yet, include it in the set of non terminals.
        nts.add(nt);
    }
    if (computeInside) {
        // Compute the inside score.
        scores[nt] = FastMath.logAdd(scores[nt], score);
        // Add a dummy backpointer, so that the above non-null check still works.
        bps[nt] = BackPointer.NON_NULL_BACKPOINTER;
    } else {
        // Compute the viterbi score.
        if (score > scores[nt]) {
            scores[nt] = score;
            bps[nt] = new BackPointer(r, mid);
        }
    }
}
 

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
public final void updateCell(int s, int t, int d, int ic, double score, int r) {
    int idx = getIndex(s, t, d, ic);
    if (this.type == DepParseType.VITERBI) {
        if (score > scores[idx]) {
            scores[idx] = score;
            bps[idx] = r;
        }
    } else {
        scores[idx] = FastMath.logAdd(scores[idx], score);
        // Don't update the backpointer.
        
        // Commented out for speed.
        //            log.debug(String.format("Cell: s=%d (r=%d) t=%d d=%s ic=%s score=%10.2f exp(score)=%.2f", 
        //                    s, r, t, 
        //                    d == ProjectiveDependencyParser.RIGHT ? "R" : "L",
        //                    ic == ProjectiveDependencyParser.COMPLETE ? "C" : "I", 
        //                    scores[s][t][d][ic], 
        //                    FastMath.exp(scores[s][t][d][ic])));
    }
}
 

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
public static double logSum(double[] logProps) {
    double logPropSum = Double.NEGATIVE_INFINITY;
    for (int d = 0; d < logProps.length; d++) {
        logPropSum = FastMath.logAdd(logPropSum, logProps[d]);
    }
    return logPropSum;
}
 

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
public static float logSum(float[] logProps) {
    float logPropSum = Float.NEGATIVE_INFINITY;
    for (int d = 0; d < logProps.length; d++) {
        logPropSum = FastMath.logAdd(logPropSum, logProps[d]);
    }
    return logPropSum;
}
 

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
public double call(double v1, double v2) {
    return FastMath.logAdd(v1, v2);
}
 

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
@Override
public double plus(double x, double y) {
    return FastMath.logAdd(x, y);
}
 

import edu.jhu.prim.util.math.FastMath; //导入方法依赖的package包/类
private void testSimpleSentence1Helper(LoopOrder loopOrder) throws IOException {
    // time flies like an arrow.
    CnfGrammarReader builder = new CnfGrammarReader();
    builder.loadFromResource(CnfGrammarReaderTest.timeFliesGrammarResource);
    CnfGrammar grammar = builder.getGrammar(loopOrder);
            
    Sentence sent = getSentenceFromString("time flies like an arrow", grammar.getLexAlphabet());
    PcfgIoChart chart = parseSentence(sent , grammar, loopOrder);
    
    // There are three valid trees with weights -11, -12, -15.
    double sum = FastMath.logAdd(-11, -12);
    sum = FastMath.logAdd(sum, -15);
    assertEquals(-10.673, sum, 1e-3);
    assertEquals(-10.660, chart.getLogInsideScore(grammar.getRootSymbol(), 0, sent.size()), 1e-3);
    assertEquals(0, chart.getLogOutsideScore(grammar.getRootSymbol(), 0, sent.size()), 1e-3);

    // Each of the three trees uses this NP from 3 to 5. So the outside
    // score should be the sums of those trees minus 3 from each of their
    // weights, since 3 is the weight of this NP.
    sum = FastMath.logAdd(-8, -9);
    sum = FastMath.logAdd(sum, -12);
    assertEquals(sum, chart.getLogOutsideScore(grammar.getNtAlphabet().lookupIndex("NP"), 3, 5), 1e-6);
    
    System.out.println("");
    int numNonInfs = 0;
    for (int width = 1; width <= sent.size(); width++) {
        for (int start = 0; start <= sent.size() - width; start++) {                                
            int end = start + width;
            
            for (int nt = 0; nt < grammar.getNumNonTerminals(); nt++) {
                String msg = String.format("start=%d end=%d nt=%s", start, end, grammar.getNtAlphabet().lookupObject(nt));
                msg += " is: " + chart.getLogInsideScore(nt, start, end) + " os: " + chart.getLogOutsideScore(nt, start, end);
                double product = chart.getLogInsideScore(nt, start, end) + chart.getLogOutsideScore(nt, start, end);
                                    
                if (product != Double.NEGATIVE_INFINITY) {
                    System.out.println(msg);
                    numNonInfs++;
                }
            }
        }
    }
    assertEquals(18, numNonInfs);
}