Hashing functions

Functions
size_t	ddd::wang32_hash (size_t key)
	Thomas Wang's 32 bit hash function.
uint32_t	ddd::int32_hash (uint32_t a)
	Another of Wang's fast hash with a magic number.
size_t	ddd::knuth32_hash (size_t key)
	Knuth's Multiplicative hash function.

Detailed Description

Function Documentation

int32_hash()

uint32_t ddd::int32_hash ( uint32_t  a )

inline

Another of Wang's fast hash with a magic number.

good for (sequence of) integers

Referenced by _GDDD::hash(), GDDD::hash(), _setVarConst::hash(), and _incVar::hash().

knuth32_hash()

size_t ddd::knuth32_hash ( size_t  key )

inline

Knuth's Multiplicative hash function.

This function is suitable for hashing values whose high order bits do not vary much (ex. addresses of memory objects). Prefer spot::wang32_hash() otherwise. http://www.concentric.net/~Ttwang/tech/addrhash.htm

Referenced by GHom::hash(), MLHom::hash(), MLShom::hash(), GSDD::hash(), and GShom::hash().

wang32_hash()

size_t ddd::wang32_hash ( size_t  key )

inline

Thomas Wang's 32 bit hash function.

Hash an integer amongst the integers. http://www.concentric.net/~Ttwang/tech/inthash.htm

Referenced by _GDDD::hash(), _VarCompState::hash(), d3::util::hash< const std::vector< int > >::operator()(), d3::util::hash< const std::vector< short > >::operator()(), and d3::util::hash< int >::operator()().