Defines for the Order Preserving Minimal Perfect Hash Map. More...

#include <stdint.h>
#include <stdlib.h>

Include dependency graph for kdbopmphm.h:

This graph shows which files directly or indirectly include this file:

Classes
struct	OpmphmEdge
	The r-partite hypergraph. More...

struct	Opmphm
	The opmphm. More...

Macros
#define	OPMPHMR_PARTITE 3
	The Order Preserving Minimal Perfect Hash Map (OPMPHM) maps each element to an edge in an r-partite hypergraph. More...

#define	OPMPHM_HASHFUNCTION_ROT(x, k) (((x) << (k)) \| ((x) >> (32 - (k))))
	Hash function By Bob Jenkins, May 2006 http://burtleburtle.net/bob/c/lookup3.c.

Typedefs
typedef const char (	opmphmGetString) (void *)
	Only needed for Initialisation.

Functions
double	opmphmMinC (void)
	Graph functions. More...

OpmphmGraph *	opmphmGraphNew (Opmphm *opmphm, size_t n, double c)
	Allocates and initializes the OpmphmGraph. More...

void	opmphmGraphDel (OpmphmGraph *graph)
	Deletes the OpmphmGraph. More...

int	opmphmMapping (Opmphm opmphm, OpmphmGraph graph, OpmphmInit *init, size_t n)
	Build functions. More...

int	opmphmAssignment (Opmphm opmphm, OpmphmGraph graph, size_t n, int defaultOrder)
	Assigns the vertices of the r-partite hypergraph. More...

size_t	opmphmLookup (Opmphm opmphm, const void name)
	Lookup functions. More...

Opmphm *	opmphmNew (void)
	Basic functions. More...

void	opmphmDel (Opmphm *opmphm)
	Deletes the OPMPHM. More...

void	opmphmClear (Opmphm *opmphm)
	Clears the OPMPHM. More...

int	opmphmIsEmpty (Opmphm *opmphm)
	Determines if the OPMPHM is Empty. More...

uint32_t	opmphmHashfunction (const void *key, size_t length, uint32_t initval)
	Hash function By Bob Jenkins, May 2006 http://burtleburtle.net/bob/c/lookup3.c Original name: hashlitte.

Detailed Description

Defines for the Order Preserving Minimal Perfect Hash Map.

Copyright: BSD License (see doc/COPYING or https://www.libelektra.org)

Macro Definition Documentation

◆ OPMPHMR_PARTITE

#define OPMPHMR_PARTITE 3

The Order Preserving Minimal Perfect Hash Map (OPMPHM) maps each element to an edge in an r-partite hypergraph.

The r-partite hypergraph consist of OPMPHMR_PARTITE components, each component has Opmphm->componentSize vertices. An edge connects OPMPHMR_PARTITE vertices, each one in separate components of the r-partite hypergraph. The number of vertices in one component of the r-partite hypergraph (Opmphm->componentSize) is calculated during opmphmGraphNew () the following way:

Opmphm->componentSize = (c * n / OPMPHMR_PARTITE) + 1;

Note that c must have a minimal value in order to generate acyclic r-partite hypergraphs. The minimal value of c depends on OPMPHMR_PARTITE and is provided by the function opmphmMinC ().

The finals size of the opmphm (Opmphm->graph) is: Opmphm->componentSize * OPMPHMR_PARTITE

Function Documentation

◆ opmphmAssignment()

int opmphmAssignment	(	Opmphm *	opmphm,
		OpmphmGraph *	graph,
		size_t	n,
		int	defaultOrder
	)

Assigns the vertices of the r-partite hypergraph.

Allocs the memory for the final OPMPHM Opmphm->graph. Uses the remove sequence OpmphmGraph->removeOrder, generated during cycle check, to assign each vertex. Either with OpmphmEdge->order or the default order, default is the order of OpmphmInit->data.

Parameters

opmphm	the OPMPHM
graph	the OpmphmGraph
n	the number of elements
defaultOrder	boolean flag

Return values

0	on success
-1	on memory error

◆ opmphmClear()

void opmphmClear ( Opmphm * opmphm )

Clears the OPMPHM.

Clears and frees all internal memory of Opmphm, but not the Opmphm instance.

Parameters

opmphm the OPMPHM

◆ opmphmDel()

void opmphmDel ( Opmphm * opmphm )

Deletes the OPMPHM.

Clears and frees all memory in Opmphm.

Parameters

opmphm the OPMPHM

◆ opmphmGraphDel()

void opmphmGraphDel ( OpmphmGraph * graph )

Deletes the OpmphmGraph.

Parameters

graph the OpmphmGraph

◆ opmphmGraphNew()

OpmphmGraph* opmphmGraphNew	(	Opmphm *	opmphm,
		size_t	n,
		double	c
	)

Allocates and initializes the OpmphmGraph.

The OpmphmGraph represents a r-partite hypergraph. Calculates also the size of one partition in the r-partite hypergraph and stores it in opmphm->componentSize.

Parameters

opmphm	the OPMPHM
n	the number of elements
c	space influencing parameter

Return values

OpmphmGraph	* success
NULL	memory error

◆ opmphmIsEmpty()

int opmphmIsEmpty ( Opmphm * opmphm )

Determines if the OPMPHM is Empty.

Empty means opmphm->size is 0.

Parameters

opmphm the OPMPHM

Return values

true	empty
false	non empty

◆ opmphmLookup()

size_t opmphmLookup	(	Opmphm *	opmphm,
		const void *	name
	)

Lookup functions.

Parameters

opmphm	the OPMPHM
name	the name of the element

Return values

size_t the order of the element.

◆ opmphmMapping()

int opmphmMapping	(	Opmphm *	opmphm,
		OpmphmGraph *	graph,
		OpmphmInit *	init,
		size_t	n
	)

Build functions.

Sets the seeds for the opmphmHashfunctions, OpmphmInit->initSeed will be changed. Inserts each element as edge in the r-partite hypergraph and checks if the graph contains a cycle.

Parameters

opmphm	the OPMPHM
graph	the OpmphmGraph
init	the OpmphmInit
n	the number of elements

Return values

0	on success
-1	mapping not possible

◆ opmphmMinC()

double opmphmMinC ( void )

Graph functions.

This minimal values come from Fabiano Cupertino Botelho, Near-Optimal Space Perfect Hashing Algorithms, 2008.

Return values

c	the minimal c value

◆ opmphmNew()

Opmphm* opmphmNew ( void )

Basic functions.

The returned OPMPHM instance is Empty.

Return values

Opmphm	* success
NULL	memory error

Classes

Macros

Typedefs

Functions

Detailed Description

Macro Definition Documentation

◆ OPMPHMR_PARTITE

Function Documentation

◆ opmphmAssignment()

◆ opmphmClear()

◆ opmphmDel()

◆ opmphmGraphDel()

◆ opmphmGraphNew()

◆ opmphmIsEmpty()

◆ opmphmLookup()

◆ opmphmMapping()

◆ opmphmMinC()

◆ opmphmNew()