Examples with RoaringBitmap org.roaringbitmap.RoaringBitmap used on opensource projects

Example 66 with RoaringBitmap

use of org.roaringbitmap.RoaringBitmap in project RoaringBitmap by RoaringBitmap.

the class CompressionResults method testSuperDense.

public static void testSuperDense() {
    System.out.println("Sparse case... universe = [0," + universe_size + ")");
    RoaringBitmap r = new RoaringBitmap();
    int howmany = 100;
    int gap = universe_size / howmany;
    for (int i = 1; i < howmany; i++) {
        r.add(i * gap + 1, ((i + 1) * gap));
    }
    System.out.println("Adding " + r.getCardinality() + " values partionned by " + howmany + " gaps of 1 ...");
    System.out.println("As a bitmap it would look like 01111...11011111... ");
    System.out.println("Bits used per value = " + F.format(r.getSizeInBytes() * 8.0 / r.getCardinality()));
    r.runOptimize();
    System.out.println("Bits used per value after run optimize = " + F.format(r.getSizeInBytes() * 8.0 / r.getCardinality()));
    System.out.println("Bits used per gap after run optimize = " + F.format(r.getSizeInBytes() * 8.0 / howmany));
    System.out.println("An uncompressed bitset might use " + F.format(universe_size * 1.0 / r.getCardinality()) + " bits per value set");
    System.out.println();
}

Example 67 with RoaringBitmap

use of org.roaringbitmap.RoaringBitmap in project RoaringBitmap by RoaringBitmap.

the class CompressionResults method testSuperSparse.

public static void testSuperSparse() {
    System.out.println("Sparse case... universe = [0," + universe_size + ")");
    RoaringBitmap r = new RoaringBitmap();
    int howmany = 100;
    int gap = universe_size / howmany;
    System.out.println("Adding " + howmany + " values separated by gaps of " + gap + "...");
    System.out.println("As a bitmap it would look like 1000...001000... ");
    for (int i = 1; i < howmany; i++) {
        r.add(i * gap);
    }
    System.out.println("Bits used per value = " + F.format(r.getSizeInBytes() * 8.0 / howmany));
    r.runOptimize();
    System.out.println("Bits used per value after run optimize = " + F.format(r.getSizeInBytes() * 8.0 / howmany));
    System.out.println("An uncompressed bitset might use " + F.format(universe_size * 1.0 / howmany) + " bits per value set");
    System.out.println();
}

Example 68 with RoaringBitmap

use of org.roaringbitmap.RoaringBitmap in project RoaringBitmap by RoaringBitmap.

the class IntervalCheck method main.

public static void main(String[] args) {
    // some bitmap
    RoaringBitmap rr = RoaringBitmap.bitmapOf(1, 2, 3, 1000);
    // we want to check if it intersects a given range [10,1000]
    int low = 10;
    int high = 1000;
    RoaringBitmap range = new RoaringBitmap();
    range.add((long) low, (long) high + 1);
    // 
    // 
    // prints true if they intersect
    System.out.println(RoaringBitmap.intersects(rr, range));
}

Example 69 with RoaringBitmap

use of org.roaringbitmap.RoaringBitmap in project RoaringBitmap by RoaringBitmap.

the class SerializeToByteArrayExample method main.

public static void main(String[] args) {
    RoaringBitmap mrb = RoaringBitmap.bitmapOf(1, 2, 3, 1000);
    System.out.println("starting with  bitmap " + mrb);
    // to improve compression
    mrb.runOptimize();
    byte[] array = new byte[mrb.serializedSizeInBytes()];
    try {
        mrb.serialize(new java.io.DataOutputStream(new java.io.OutputStream() {

            int c = 0;

            @Override
            public void close() {
            }

            @Override
            public void flush() {
            }

            @Override
            public void write(int b) {
                array[c++] = (byte) b;
            }

            @Override
            public void write(byte[] b) {
                write(b, 0, b.length);
            }

            @Override
            public void write(byte[] b, int off, int l) {
                System.arraycopy(b, off, array, c, l);
                c += l;
            }
        }));
    } catch (IOException ioe) {
        // should never happen because we write to a byte array
        throw new RuntimeException("unexpected error while serializing to a byte array");
    }
    RoaringBitmap ret = new RoaringBitmap();
    try {
        ret.deserialize(new java.io.DataInputStream(new java.io.InputStream() {

            int c = 0;

            @Override
            public int read() {
                return array[c++] & 0xff;
            }

            @Override
            public int read(byte[] b) {
                return read(b, 0, b.length);
            }

            @Override
            public int read(byte[] b, int off, int l) {
                System.arraycopy(array, c, b, off, l);
                c += l;
                return l;
            }
        }));
    } catch (IOException ioe) {
        // should never happen because we read from a byte array
        throw new RuntimeException("unexpected error while deserializing from a byte array");
    }
    if (!ret.equals(mrb))
        throw new RuntimeException("bug");
    System.out.println("decoded from byte array : " + ret);
}

Example 70 with RoaringBitmap

use of org.roaringbitmap.RoaringBitmap in project presto by prestodb.

the class HiveManifestUtils method decompressFileNames.

static List<String> decompressFileNames(String compressedFileNames) {
    // Check if the compressed fileNames string is a number
    if (compressedFileNames.matches("\\d+")) {
        long end = Long.parseLong(compressedFileNames);
        if (end == 0) {
            return ImmutableList.of("0");
        }
        return LongStream.range(0, end + 1).mapToObj(String::valueOf).collect(toImmutableList());
    }
    try {
        RoaringBitmap roaringBitmap = new RoaringBitmap();
        ByteBuffer byteBuffer = ByteBuffer.wrap(compressedFileNames.getBytes(ISO_8859_1));
        roaringBitmap.deserialize(byteBuffer);
        return Arrays.stream(roaringBitmap.toArray()).mapToObj(Integer::toString).collect(toImmutableList());
    } catch (IOException e) {
        throw new PrestoException(MALFORMED_HIVE_FILE_STATISTICS, "Failed de-compressing the file names in manifest");
    }
}