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Example 1 with ArrayOfBooleansSerDe

use of com.yahoo.sketches.ArrayOfBooleansSerDe in project sketches-core by DataSketches.

the class VarOptItemsSketch method heapify.

/**
   * Returns a sketch instance of this class from the given srcMem,
   * which must be a Memory representation of this sketch class.
   *
   * @param <T>    The type of item this sketch contains
   * @param srcMem a Memory representation of a sketch of this class.
   *               <a href="{@docRoot}/resources/dictionary.html#mem">See Memory</a>
   * @param serDe  An instance of ArrayOfItemsSerDe
   * @return a sketch instance of this class
   */
@SuppressWarnings("null")
public static <T> VarOptItemsSketch<T> heapify(final Memory srcMem, final ArrayOfItemsSerDe<T> serDe) {
    final int numPreLongs = getAndCheckPreLongs(srcMem);
    final ResizeFactor rf = ResizeFactor.getRF(extractResizeFactor(srcMem));
    final int serVer = extractSerVer(srcMem);
    final int familyId = extractFamilyID(srcMem);
    final int flags = extractFlags(srcMem);
    final boolean isEmpty = (flags & EMPTY_FLAG_MASK) != 0;
    final boolean isGadget = (flags & GADGET_FLAG_MASK) != 0;
    // Check values
    if (numPreLongs != Family.VAROPT.getMinPreLongs() && numPreLongs != Family.VAROPT.getMaxPreLongs() && numPreLongs != PreambleUtil.VO_WARMUP_PRELONGS) {
        throw new SketchesArgumentException("Possible corruption: Must have " + Family.VAROPT.getMinPreLongs() + ", " + PreambleUtil.VO_WARMUP_PRELONGS + ", or " + Family.VAROPT.getMaxPreLongs() + " preLongs. Found: " + numPreLongs);
    }
    if (serVer != SER_VER) {
        throw new SketchesArgumentException("Possible Corruption: Ser Ver must be " + SER_VER + ": " + serVer);
    }
    final int reqFamilyId = Family.VAROPT.getID();
    if (familyId != reqFamilyId) {
        throw new SketchesArgumentException("Possible Corruption: FamilyID must be " + reqFamilyId + ": " + familyId);
    }
    final int k = extractK(srcMem);
    if (k < 2) {
        throw new SketchesArgumentException("Possible Corruption: k must be at least 2: " + k);
    }
    if (isEmpty) {
        assert numPreLongs == Family.VAROPT.getMinPreLongs();
        return new VarOptItemsSketch<>(k, rf);
    }
    final long n = extractN(srcMem);
    if (n < 0) {
        throw new SketchesArgumentException("Possible Corruption: n cannot be negative: " + n);
    }
    // get rest of preamble
    final int hCount = extractHRegionItemCount(srcMem);
    final int rCount = extractRRegionItemCount(srcMem);
    if (hCount < 0) {
        throw new SketchesArgumentException("Possible Corruption: H region count cannot be " + "negative: " + hCount);
    }
    if (rCount < 0) {
        throw new SketchesArgumentException("Possible Corruption: R region count cannot be " + "negative: " + rCount);
    }
    double totalRWeight = 0.0;
    if (numPreLongs == Family.VAROPT.getMaxPreLongs()) {
        if (rCount > 0) {
            totalRWeight = extractTotalRWeight(srcMem);
        } else {
            throw new SketchesArgumentException("Possible Corruption: " + Family.VAROPT.getMaxPreLongs() + " preLongs but no items in R region");
        }
    }
    final int preLongBytes = numPreLongs << 3;
    final int totalItems = hCount + rCount;
    // default to full
    int allocatedItems = k + 1;
    if (rCount == 0) {
        // Not in sampling mode, so determine size to allocate, using ceilingLog2(hCount) as minimum
        final int ceilingLgK = Util.toLog2(Util.ceilingPowerOf2(k), "heapify");
        final int minLgSize = Util.toLog2(Util.ceilingPowerOf2(hCount), "heapify");
        final int initialLgSize = SamplingUtil.startingSubMultiple(ceilingLgK, rf.lg(), Math.max(minLgSize, MIN_LG_ARR_ITEMS));
        allocatedItems = SamplingUtil.getAdjustedSize(k, 1 << initialLgSize);
        if (allocatedItems == k) {
            ++allocatedItems;
        }
    }
    // allocate full-sized ArrayLists, but we store only hCount weights at any moment
    final long weightOffsetBytes = TOTAL_WEIGHT_R_DOUBLE + (rCount > 0 ? Double.BYTES : 0);
    final ArrayList<Double> weightList = new ArrayList<>(allocatedItems);
    final double[] wts = new double[allocatedItems];
    srcMem.getDoubleArray(weightOffsetBytes, wts, 0, hCount);
    // can't use Arrays.asList(wts) since double[] rather than Double[]
    for (int i = 0; i < hCount; ++i) {
        if (wts[i] <= 0.0) {
            throw new SketchesArgumentException("Possible Corruption: " + "Non-positive weight in heapify(): " + wts[i]);
        }
        weightList.add(wts[i]);
    }
    // marks, if we have a gadget
    long markBytes = 0;
    int markCount = 0;
    ArrayList<Boolean> markList = null;
    if (isGadget) {
        final long markOffsetBytes = preLongBytes + (hCount * Double.BYTES);
        markBytes = ArrayOfBooleansSerDe.computeBytesNeeded(hCount);
        markList = new ArrayList<>(allocatedItems);
        final ArrayOfBooleansSerDe booleansSerDe = new ArrayOfBooleansSerDe();
        final Boolean[] markArray = booleansSerDe.deserializeFromMemory(srcMem.region(markOffsetBytes, (hCount >> 3) + 1), hCount);
        for (Boolean mark : markArray) {
            if (mark) {
                ++markCount;
            }
        }
        markList.addAll(Arrays.asList(markArray));
    }
    final long offsetBytes = preLongBytes + (hCount * Double.BYTES) + markBytes;
    final T[] data = serDe.deserializeFromMemory(srcMem.region(offsetBytes, srcMem.getCapacity() - offsetBytes), totalItems);
    final List<T> wrappedData = Arrays.asList(data);
    final ArrayList<T> dataList = new ArrayList<>(allocatedItems);
    dataList.addAll(wrappedData.subList(0, hCount));
    // Load items in R as needed
    if (rCount > 0) {
        // the gap
        weightList.add(-1.0);
        // the gap
        if (isGadget) {
            markList.add(false);
        }
        for (int i = 0; i < rCount; ++i) {
            weightList.add(-1.0);
            if (isGadget) {
                markList.add(false);
            }
        }
        // the gap
        dataList.add(null);
        dataList.addAll(wrappedData.subList(hCount, totalItems));
    }
    final VarOptItemsSketch<T> sketch = new VarOptItemsSketch<>(dataList, weightList, k, n, allocatedItems, rf, hCount, rCount, totalRWeight);
    if (isGadget) {
        sketch.marks_ = markList;
        sketch.numMarksInH_ = markCount;
    }
    return sketch;
}
Also used : ArrayOfBooleansSerDe(com.yahoo.sketches.ArrayOfBooleansSerDe) ArrayList(java.util.ArrayList) ResizeFactor(com.yahoo.sketches.ResizeFactor) PreambleUtil.extractResizeFactor(com.yahoo.sketches.sampling.PreambleUtil.extractResizeFactor) SketchesArgumentException(com.yahoo.sketches.SketchesArgumentException)

Aggregations

ArrayOfBooleansSerDe (com.yahoo.sketches.ArrayOfBooleansSerDe)1 ResizeFactor (com.yahoo.sketches.ResizeFactor)1 SketchesArgumentException (com.yahoo.sketches.SketchesArgumentException)1 PreambleUtil.extractResizeFactor (com.yahoo.sketches.sampling.PreambleUtil.extractResizeFactor)1 ArrayList (java.util.ArrayList)1