NAME
pds.db - small database with planar difference set samples
VERSION
This is version 2.0 of the database, created on May 9, 2021.
DESCRIPTION
This file is the default database distributed with the Perl 5 module Math::DifferenceSet::Planar.
It contains 604 cyclic planar difference sets with orders ranging from 2 to 4096. The sets are chosen minimal by lexicographic ordering. It also contains planar difference set space data for the same range of orders.
FILE FORMAT
SQLite 3.x database.
SCHEMA
CREATE TABLE difference_set (
order_ integer NOT NULL PRIMARY KEY,
base integer NOT NULL,
exponent integer NOT NULL,
modulus integer NOT NULL,
n_planes integer NOT NULL,
deltas blob NOT NULL
);
CREATE TABLE difference_set_space (
order_ integer NOT NULL PRIMARY KEY,
mul_radix integer NOT NULL,
mul_depth integer NOT NULL,
rot_radices blob NOT NULL,
rot_depths blob NOT NULL
);
DATA REPRESENTATION
If D = { d_1, d_2, ..., d_k } (mod m) is a canonical cyclic planar difference set of order k - 1 with d_1 ≡ 0 and d_2 ≡ 1 (mod m), deltas is a sequence of k - 2 numeric values packed in 'w*'
format, calculated as differences of consecutive residue values of D starting with d_3 - d_2. The difference of the smallest two values in a canonical set is always 1 and thus not important to store.
If a multiplier set of the form {b^k | 0 ≤ k < e} with a radix b and depth e, and a rotator base of the form {r_1^j_1·r_2·j_2·...·r_n^j_n | 0 ≤ j_k < d_k, 1 ≤ k ≤ n} with n radices r_k and n depths d_k describe the multiplicative space of difference set planes of a given order, rot_radices and rot_depths are vectors of rotation radices and depths packed in 'w*'
format.
PROVIDER
Martin Becker, <becker-cpan-mp at cozap.com>
COPYRIGHT AND LICENSE
Copyright (c) 2019-2021 by Martin Becker, Blaubeuren.
This library is free software; you can distribute it and/or modify it under the terms of the Artistic License 2.0 (see the LICENSE file).
The contents of this database are mathematically defined entities. The provider believes mathematical constants not to be proprietary or subject to copyright legislation, although the software used to calculate them and the accompanying documentation certainly are.