/// <summary>
/// Returns the popcount or cardinality of "a and not b"
/// or "intersection(a, not(b))".
/// Neither set is modified.
/// </summary>
public static long AndNotCount(OpenBitSet a, OpenBitSet b)
{
long tot = BitUtil.Pop_AndNot(a.m_bits, b.m_bits, 0, Math.Min(a.m_wlen, b.m_wlen));
if (a.m_wlen > b.m_wlen)
{
tot += BitUtil.Pop_Array(a.m_bits, b.m_wlen, a.m_wlen - b.m_wlen);
}
return(tot);
}
/// <summary>
/// Returns the popcount or cardinality of "a and not b" or
/// "intersection(a, not(b))". Neither set is modified.
/// </summary>
public static long AndNotCount(FixedBitSet a, FixedBitSet b)
{
long tot = BitUtil.Pop_AndNot(a.bits, b.bits, 0, Math.Min(a.numWords, b.numWords));
if (a.numWords > b.numWords)
{
tot += BitUtil.Pop_Array(a.bits, b.numWords, a.numWords - b.numWords);
}
return(tot);
}
/// <summary>
/// Returns the popcount or cardinality of the union of the two sets. Neither
/// set is modified.
/// </summary>
public static long UnionCount(FixedBitSet a, FixedBitSet b)
{
long tot = BitUtil.Pop_Union(a.bits, b.bits, 0, Math.Min(a.numWords, b.numWords));
if (a.numWords < b.numWords)
{
tot += BitUtil.Pop_Array(b.bits, a.numWords, b.numWords - a.numWords);
}
else if (a.numWords > b.numWords)
{
tot += BitUtil.Pop_Array(a.bits, b.numWords, a.numWords - b.numWords);
}
return(tot);
}
/// <summary>
/// Returns the popcount or cardinality of the exclusive-or of the two sets.
/// Neither set is modified.
/// </summary>
public static long XorCount(OpenBitSet a, OpenBitSet b)
{
long tot = BitUtil.Pop_Xor(a.m_bits, b.m_bits, 0, Math.Min(a.m_wlen, b.m_wlen));
if (a.m_wlen < b.m_wlen)
{
tot += BitUtil.Pop_Array(b.m_bits, a.m_wlen, b.m_wlen - a.m_wlen);
}
else if (a.m_wlen > b.m_wlen)
{
tot += BitUtil.Pop_Array(a.m_bits, b.m_wlen, a.m_wlen - b.m_wlen);
}
return(tot);
}
/// <summary>
/// Returns number of set bits. NOTE: this visits every
/// <see cref="long"/> in the backing bits array, and the result is not
/// internally cached!
/// </summary>
public int Cardinality()
{
return((int)BitUtil.Pop_Array(bits, 0, bits.Length));
}
/*
* public static int pop(long v0, long v1, long v2, long v3) {
* // derived from pop_array by setting last four elems to 0.
* // exchanges one pop() call for 10 elementary operations
* // saving about 7 instructions... is there a better way?
* long twosA=v0 & v1;
* long ones=v0^v1;
*
* long u2=ones^v2;
* long twosB =(ones&v2)|(u2&v3);
* ones=u2^v3;
*
* long fours=(twosA&twosB);
* long twos=twosA^twosB;
*
* return (pop(fours)<<2)
+ (pop(twos)<<1)
+ pop(ones);
+ }
*/
/// <summary>
/// Get the number of set bits.
/// </summary>
/// <returns> The number of set bits. </returns>
public virtual long Cardinality()
{
return(BitUtil.Pop_Array(m_bits, 0, m_wlen));
}
public long Cardinality()
{
return(BitUtil.Pop_Array(bits, 0, bits.Length));
}