Examples with FingerPrint il.technion.tinytable.hash.FingerPrint used on opensource projects

Example 1 with FingerPrint

use of il.technion.tinytable.hash.FingerPrint in project narchy by automenta.

the class TinyCountingTable method shrinkChain.

/**
 * If the value of an item is reduced we may need a new number of items.
 * We therefore update the index and remove an arbitrary item from its chain.
 *
 * @param bucketId
 * @param chainId
 */
private void shrinkChain(int bucketId, int chainId) {
    this.removeAndShrink(bucketId);
    int bucket;
    int il = this.I0.length;
    for (int i = bucketId + 1; i < bucketId + il; i++) {
        bucket = (i) % il;
        if (A[bucket] > 0) {
            removeAndShrink(bucket);
            A[bucket]--;
        } else {
            break;
        }
    }
    removeItemFromIndex(new FingerPrint(bucketId, chainId, 1L));
}

Example 2 with FingerPrint

use of il.technion.tinytable.hash.FingerPrint in project narchy by automenta.

the class TinyTable method add.

/**
 * Adds a new fingerPrint to the following bucketNumber and chainNumber, the maximal size
 * of supported fingerprint is 64 bits, and it is assumed that the actual data sits on the LSB bits of
 * long.
 * <p>
 * According to our protocol, addition of a fingerprint may result in expending the bucket on account of neighboring buckets,
 * or down sizing the stored fingerprints to make room for the new one.
 * <p>
 * In order to support deletions, deleted items are first logically deleted, and are fully
 * deleted only upon addition.
 *  @param bucketNumber
 * @param chainNumber
 * @param fingerPrint
 */
int add(FingerPrint fpAux) {
    int nextBucket = this.findFreeBucket(fpAux.bucketId);
    upscaleBuckets(fpAux.bucketId, nextBucket);
    int idxToAdd = RankIndexing.addItem(fpAux, I0, IStar, offsets, chain);
    // if we need to, we steal items from other buckets.
    this.putAndPush(fpAux.bucketId, idxToAdd, fpAux.fingerprint);
    return idxToAdd;
}

Example 3 with FingerPrint

use of il.technion.tinytable.hash.FingerPrint in project narchy by automenta.

the class RankIndexingTechnqiueUnitTest method TestRemove.

@Test
public void TestRemove() {
    long[] I0 = new long[1];
    long[] IStar = new long[1];
    byte[] offsets = new byte[64];
    byte[] chain = new byte[64];
    FingerPrint fpaux = new FingerPrint(0, 4, 1);
    // add an item!
    RankIndexing.addItem(fpaux, I0, IStar, offsets, chain);
    // check that item chain exists
    assertTrue(RankIndexing.chainExist(I0[0], 4));
    // get the chain
    int chainSize = RankIndexing.getChainAndUpdateOffsets(fpaux, I0, IStar, offsets, chain);
    // assert that it is of size 1.
    assertTrue(chainSize == 1);
    // remove the item - update the chain size.
    RankIndexing.RemoveItem(4, I0, IStar, 0, offsets, chain, chainSize - 1);
    // verify that the chain does not exist anymore.
    chainSize = RankIndexing.getChainAndUpdateOffsets(fpaux, I0, IStar, offsets, chain);
    assertTrue(chainSize == 0);
    assertTrue(chain[0] == -1);
}

Example 4 with FingerPrint

use of il.technion.tinytable.hash.FingerPrint in project narchy by automenta.

the class TinyCountingTable method adjustChainToItems.

/**
 * After storing a value the number of items in the chain may change, this function adjust the number to be sufficient for all fingerprint items and counter items.
 *
 * @param bucketId
 * @param chainId
 * @param items
 * @return
 */
private IntList adjustChainToItems(int bucketId, int chainId, PrimitiveIterable items) {
    IntArrayList chain = RankIndexing.getChain(chainId, I0[bucketId], IStar[bucketId], this.bucketCapacity);
    FingerPrint fpaux = new FingerPrint(bucketId, chainId, 1L);
    // if the chain is shorter than needed we add dummy items.
    int cs = chain.size();
    int is = items.size();
    if (cs < is) {
        int diff = is - cs;
        while (diff > 0) {
            this.add(fpaux);
            diff--;
        }
    } else // if the chain is longer than needed we remove items.
    if (cs > is) {
        int diff = cs - is;
        while (diff > 0) {
            shrinkChain(bucketId, chainId);
            diff--;
        // this.nrItems--;
        }
    }
    chain = RankIndexing.getChain(chainId, I0[bucketId], IStar[bucketId], bucketCapacity);
    return chain;
}

Example 5 with FingerPrint

use of il.technion.tinytable.hash.FingerPrint in project narchy by automenta.

the class TinyTable method moveToEnd.

private int moveToEnd(FingerPrint fpaux) {
    int chainoffset = RankIndexing.getChainAndUpdateOffsets(fpaux, I0, IStar, offsets, chain) - 1;
    // for (Integer itemOffset : chain) {
    // 
    // if(itemOffset<0){
    // throw new RuntimeException("Item is not there!");
    // }
    int itemOffset = this.find(fpaux);
    if (itemOffset < 0)
        return -1;
    // throw new RuntimeException("Not found!");
    int lastOffset = chain[chainoffset];
    long lastItem = this.get(fpaux.bucketId, lastOffset);
    // assertTrue(chain.containsitemOffset));
    this.set(fpaux.bucketId, itemOffset, lastItem);
    this.set(fpaux.bucketId, lastOffset, 0L);
    return lastOffset;
}