Hi,

I am new to the mailing list. It is about fastbit 1.3.6 and 1.3.7 on a linux 
machine.

I am "AND-ing" two bitvectors together.

The 1st vector: v_vect1, original bitvector, size=42106416, cnt=42106416, 
bytes=44, isCompressed=0
Its bytes:  \xBF\xB9\x14\xC0\xFF\x7F\x00\x00\x0F\x00\x00\x00
So the words are:  C014B9BF 00007FFF  0000000F

The 2nd vector: size=42106416, cnt=2922440, bytes=3512672, isCompressed=0

The result vector:  size=42106416, cnt=2922440, bytes=40, isCompressed=1

Question 1:
when I iterate through the result vector using
"for (ibis::bitvector::const_iterator v_iter = p_ptr_bitvector->begin(); v_iter 
!= p_ptr_bitvector->end(); ++v_iter)",
It only runs up to 15 bits.

Is this a expected behavior for iteration?

Question 2:
The result vector as it is written to words and printed as bytes.
They (bytes sequence) are: \x00\x00\x00\x00\x0F\x00\x00\x00

When the result vector is decompressed, it has long byte sequence.

I read your thesis about WAH, had difficult to interpret the bitmap above.
Can you please help?

Question 3:

If the result vector is stored as bytes sequence and uses it later in fastbit 
again,
Say engaged in BIT-AND operation, the bytes-sequence is treated as 
un-compressed.

How can I make it treated as compressed, like when right after the 
result-vector is generated?

Thanks

Jilong Wang



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