sourcesmith / compressedbitset Goto Github PK

To reproduce this bug, run this simple test case . . . 

import junit.framework.TestCase;

import org.devbrat.util.WAHBitSet;

public class WahBitSetTest extends TestCase {

    public void testIt() {

        int maxSize = 10000;
        int bitsToSet = 100;

        WAHBitSet allOnes = new WAHBitSet();
        for (int i = 0; i < maxSize; i++) {
            allOnes.set(i);
        }

        WAHBitSet partialOnes = new WAHBitSet();
        for (int j = maxSize - bitsToSet; j < maxSize; j++) {
            partialOnes.set(j);
        }

        assertEquals(maxSize - (maxSize - bitsToSet), allOnes.andSize(partialOnes));
    }
}

The expected result of the andSize() call should be 100, but it is 38.  If you 
play around with the numbers, this will start working again when you set the 
bitsToSet variable to 69 (i.e., it breaks at 70, but works fine at 69 and 
lower.)

I realize that this project is mostly dormant, but any thoughts from the author 
or other users would be appreciated.  This is a major bug.

Hi,
Recently, I have tried to run your project in eclipse. However, eclipse
complains about methods from the IntArrayList. For example, you call int v
= vec.get(idx); (line 929) in WAHBitSet.java. The variable v expects the
get method to return an int type. But, in the IntArrayList class provided,
the method get returns an Object. Only getQuick() in IntArrayList returns
an int type. Are you using a different IntArrayList class? If so, where can
I get this class?

Thanks,
Cong,

Some operations can be done with both uncompressed and compressed bitsets.
I plan to add those operations.

Now the code throws an exception if you set a bit inside the compressed
bitmap. That should be removed.

What steps will reproduce the problem?
1. create a compressed bitset
2. try to iterate over it using the WAHIterator

What version of the product are you using? On what operating system?
0.1

Please provide any additional information below.
WAHIterator.next() calls nextDoc and an ArrayIndexOutOfBoundsException gets
thrown at pos[pos_idx++];

Apparently pos has length 0, pos_idx is 0. The current word is marked as
being a non-range word, but it doesn't contain any indices?

Please add methods to serialize the bitset to an array of bytes or ints,
this way one can initialize the bitmap from a byte or int array

Thanks

I'm thinking about exporting this project to github, or you guys don't want to. 
:)  I don't want it to seem like I'm the author of the project, though, so I'll 
wait.

Currently it seems that API allow only a explicitly setting a bit position
value to 1. But there are occasions that this value has to be explicitly
set to zero and flip a one to zero. 

What steps will reproduce the problem?

import org.devbrat.util.WAHBitSet;

import junit.framework.TestCase;

public class TestAnd extends TestCase {

    public void testAnd() throws Exception {
        int[] s1 = new int[] { 99, 185, 240, 250, 265, 283, 312, 457, 488, 516,
                673, 775, 809, 954, 974 };
        int[] s2 = new int[] { 97, 160, 230, 237, 253, 254, 298, 309, 330, 358,
                383, 443, 481, 523, 589, 607, 748, 775, 941, 947 };
        WAHBitSet bs1 = fromInts(s1);
        WAHBitSet bs2 = fromInts(s2);
        WAHBitSet and = bs1.and(bs2);
        // should be 775, but get 868
        assertEquals(775, and.iterator().next());
    }

    private WAHBitSet fromInts(int[] ints) {
        WAHBitSet bitSet = new WAHBitSet();
        for (int i : ints) {
            bitSet.set(i);
        }
        return bitSet;
    }

}

What version of the product are you using? On what operating system?

v0.1, windows xp sp3, jdk 6 update 6