cmph(1) minimum perfect hashing tool

SYNOPSIS

cmph [-v] [-h] [-V] [-k nkeys] [-f hash_function] [-g [-c value][-s seed] ] [-a algorithm] [-M memory_in_MB] [-b BRZ_parameter] [-d tmp_dir] [-m file.mph] keysfile

DESCRIPTION

Command line tool to generate and query minimal perfect hash functions.

Please refer to http://cmph.sf.net for full documentation.

-h
Print an help message
-c
This value determines: the number of vertices in the graph for the algorithms BMZ and CHM; the number of bits per key required in the FCH algorithm
-a
Algorithm. Valid values are: bmz, bmz8, chm, brz, fch
-f
hash function (may be used multiple times). valid values are: djb2, fnv, jenkins, sdbm
-V      
Print version number and exit
-v
Increase verbosity (may be used multiple times)
-k
Number of keys
-g
Generation mode
-s
Random seed
-m
Minimum perfect hash function file
-M
Main memory availability (in MB)
-d
Temporary directory used in brz algorithm
-b
Parameter of BRZ algorithm to make the maximal number of keys in a bucket lower than 256
keysfile
Line separated file with keys

EXAMPLE

$ # Using the default algorithm (chm) for constructing a mphf
$ # for keys in file keys_file. Lines in keys_file _must_ be unique.
$ ./cmph -v -g keys_file
$ # Query id of keys in the file keys_query
$ ./cmph -v -m keys_file.mph keys_query

AUTHOR

This manual page was written by Enrico Tassi <[email protected]>, for the Debian project (but may be used by others).