| java.lang.Object
 org.apache.solr.util.BitUtil
| BitUtil | | public class BitUtil (Code) | | A variety of high efficiencly bit twiddling routines.
author:
yonik
version:
$Id$ |
| Field Summary | |
| final public static byte[] | ntzTable
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| Method Summary | |
| public static boolean | isPowerOfTwo(int v)
| | public static boolean | isPowerOfTwo(long v)
| | public static int | nextHighestPowerOfTwo(int v)
| | public static long | nextHighestPowerOfTwo(long v)
| | public static int | ntz(long val)
Returns number of trailing zeros in the 64 bit long value. | | public static int | ntz2(long x)
| | public static int | ntz3(long x)
| | public static int | pop(long x)
| | public static long | pop_andnot(long A, long B, int wordOffset, int numWords)
Returns the popcount or cardinality of A & ~B
Neither array is modified. | | public static long | pop_array(long A, int wordOffset, int numWords)
Returns the number of set bits in an array of longs. | | public static long | pop_intersect(long A, long B, int wordOffset, int numWords)
Returns the popcount or cardinality of the two sets after an intersection. | | public static long | pop_union(long A, long B, int wordOffset, int numWords)
Returns the popcount or cardinality of the union of two sets. | | public static long | pop_xor(long A, long B, int wordOffset, int numWords)
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| ntzTable | | final public static byte[] ntzTable(Code) | | table of number of trailing zeros in a byte
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| isPowerOfTwo | | public static boolean isPowerOfTwo(int v)(Code) | | returns true if v is a power of two or zero
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| isPowerOfTwo | | public static boolean isPowerOfTwo(long v)(Code) | | returns true if v is a power of two or zero
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| nextHighestPowerOfTwo | | public static int nextHighestPowerOfTwo(int v)(Code) | | returns the next highest power of two, or the current value if it's already a power of two or zero
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| nextHighestPowerOfTwo | | public static long nextHighestPowerOfTwo(long v)(Code) | | returns the next highest power of two, or the current value if it's already a power of two or zero
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| ntz | | public static int ntz(long val)(Code) | | Returns number of trailing zeros in the 64 bit long value.
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| ntz2 | | public static int ntz2(long x)(Code) | | returns 0 based index of first set bit
(only works for x!=0)
This is an alternate implementation of ntz()
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| ntz3 | | public static int ntz3(long x)(Code) | | returns 0 based index of first set bit
This is an alternate implementation of ntz()
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| pop | | public static int pop(long x)(Code) | | Returns the number of bits set in the long
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| pop_andnot | | public static long pop_andnot(long A, long B, int wordOffset, int numWords)(Code) | | Returns the popcount or cardinality of A & ~B
Neither array is modified.
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| pop_array | | public static long pop_array(long A, int wordOffset, int numWords)(Code) | | Returns the number of set bits in an array of longs.
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| pop_intersect | | public static long pop_intersect(long A, long B, int wordOffset, int numWords)(Code) | | Returns the popcount or cardinality of the two sets after an intersection.
Neither array is modified.
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| pop_union | | public static long pop_union(long A, long B, int wordOffset, int numWords)(Code) | | Returns the popcount or cardinality of the union of two sets.
Neither array is modified.
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| pop_xor | | public static long pop_xor(long A, long B, int wordOffset, int numWords)(Code) | | |
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