Class BitUtil

A variety of high efficiency bit twiddling routines.

@lucene.internal

Inheritance
System.Object
BitUtil
Assembly: DistributedLucene.Net.dll
Syntax
public sealed class BitUtil : object

Methods

Name Description
BitCount(Byte)

Return the number of bits sets in b.

BitList(Byte)

Return the list of bits which are set in b encoded as followed:

(i >>> (4 * n)) & 0x0F
is the offset of the n-th set bit of

the given byte plus one, or 0 if there are n or less bits set in the given byte. For example 

bitList(12)
returns 0x43: 
  • 0x43 & 0x0F
    is 3, meaning the the first bit set is at offset 3-1 = 2,
  • (0x43 >>> 4) & 0x0F
    is 4, meaning there is a second bit set at offset 4-1=3,
  • (0x43 >>> 8) & 0x0F
    is 0, meaning there is no more bit set in this byte.
NextHighestPowerOfTwo(Int32)

Returns the next highest power of two, or the current value if it's already a power of two or zero

NextHighestPowerOfTwo(Int64)

Returns the next highest power of two, or the current value if it's already a power of two or zero

Pop_AndNot(Int64[], Int64[], Int32, Int32)

Returns the popcount or cardinality of A & ~B. Neither array is modified.
Pop_Array(Int64[], Int32, Int32)

Returns the number of set bits in an array of s.

Pop_Intersect(Int64[], Int64[], Int32, Int32)

Returns the popcount or cardinality of the two sets after an intersection. Neither array is modified.
Pop_Union(Int64[], Int64[], Int32, Int32)

Returns the popcount or cardinality of the union of two sets. Neither array is modified.
Pop_Xor(Int64[], Int64[], Int32, Int32)

Returns the popcount or cardinality of A ^ B Neither array is modified.

Extension Methods