NAME
Math::NumSeq  number sequences
SYNOPSIS
# only a base class, use one of the actual classes such as
use Math::NumSeq::Squares;
my $seq = Math::NumSeq::Squares>new;
my ($i, $value) = $seq>next;
DESCRIPTION
This is a base class for number sequences. Sequence objects can iterate through the values, and some sequences have random access and predicate. It's a touch rough yet.
The idea is to generate things like squares or primes in a generic way. Some sequences, like squares, are so easy there's no need for this except for the genericness. Other sequences are trickier and an iterator is a good way to go through the values.
FUNCTIONS
In the following "Foo" is one of the actual subclass names. The intention is that all modules Math::NumSeq::Something
are sequence classes, and that supporting things are deeper, such as under Math::NumSeq::Something::Helper
or Math::NumSeq::Base::SharedStuff
.
$seq = Math::NumSeq::Foo>new (key=>value,...)

Create and return a new sequence object.
($i, $value) = $seq>next()

Return the next index and value in the sequence.
$seq>rewind()

Rewind the sequence to its starting point.
$str = $seq>description()

A humanreadable description of the sequence.
$value = $seq>values_min()
$value = $seq>values_max()

Return the minimum or maximum value taken by values in the sequence, or
undef
if unknown or infinity. $ret = $seq>characteristic($key)

Return something if the sequence has a
$key
(a string) characteristic, orundef
if not. This is intended as a loose set of expressing features or properties a sequence might have.digits the radix (an integer), if sequence is digits
$str = $seq>oeis_anum()

Return the Online Encyclopedia of Integer Sequences Anumber (a string) of
$seq
, orundef
if not in the OEIS or not known. For examplemy $seq = Math::NumSeq::Squares>new; my $anum = $seq>oeis_anum; # gives $anum eq "A000290"
The web page for that is then
http://oeis.org/A000290
Sometimes the OEIS has duplicates, ie. two Anumbers which are the same sequence.
$seq>oeis_anum()
generally returns whichever is the primary one, at least for accidental duplication. $aref = Math::NumSeq::Foo>parameter_info_array()
@list = Math::NumSeq::Foo>parameter_info_list()

Return an arrayref of list describing the parameters taken by a given class. This meant to help making widgets etc for user interaction in a GUI. Each element is a hashref
{ name => parameter key arg for new() description => human readable string type => string "integer","boolean","enum" etc default => value minimum => number, or undef maximum => number, or undef width => integer, suggested display size choices => for enum, an arrayref }
type
is a string, one of"integer" "enum" "boolean" "string" "filename"
"filename" is separate from "string" since it might require subtly different handling to ensure it reaches Perl as a byte string, whereas a "string" type might in principle take Perl wide chars.
For "enum" the
choices
field is the possible values, such as{ name => "flavour", type => "enum", choices => ["strawberry","chocolate"], }
minimum
andmaximum
are omitted if there's no hard limit on the parameter.
Optional Methods
The following methods are only implemented for some sequences, since it's sometimes difficult to generate an arbitrary numbered element etc. Check with $seq>can('ith')
etc before using.
$value = $seq>ith($i)

Return the
$i
'th value in the sequence. Only some sequence classes implement this method. $bool = $seq>pred($value)

Return true if
$value
occurs in the sequence. For example for the squares this would return true if$value
is a square or false if not.
SEE ALSO
Math::NumSeq::Squares, Math::NumSeq::Cubes, Math::NumSeq::Pronic, Math::NumSeq::Triangular, Math::NumSeq::Polygonal, Math::NumSeq::Tetrahedral, Math::NumSeq::StarNumbers, Math::NumSeq::Even, Math::NumSeq::Odd, Math::NumSeq::All
Math::NumSeq::Primes, Math::NumSeq::TwinPrimes, Math::NumSeq::SophieGermainPrimes, Math::NumSeq::Emirps, Math::NumSeq::MobiusFunction, Math::NumSeq::PrimeFactorCount, Math::NumSeq::DivisorCount,
Math::NumSeq::Totient, Math::NumSeq::TotientCumulative, Math::NumSeq::TotientSteps, Math::NumSeq::TotientPerfect
Math::NumSeq::Factorials, Math::NumSeq::Primorials, Math::NumSeq::Fibonacci, Math::NumSeq::LucasNumbers, Math::NumSeq::Fibbinary, Math::NumSeq::Pell, Math::NumSeq::Tribonacci
Math::NumSeq::FractionDigits, Math::NumSeq::SqrtDigits
Math::NumSeq::DigitCount, Math::NumSeq::DigitLength, Math::NumSeq::DigitLengthCumulative, Math::NumSeq::DigitProduct, Math::NumSeq::DigitSum, Math::NumSeq::DigitSumModulo, Math::NumSeq::RadixWithoutDigit
Math::NumSeq::Palindromes, Math::NumSeq::Beastly, Math::NumSeq::Repdigits, Math::NumSeq::HarshadNumbers, Math::NumSeq::HappyNumbers
Math::NumSeq::CullenNumbers, Math::NumSeq::ProthNumbers, Math::NumSeq::WoodallNumbers Math::NumSeq::BaumSweet, Math::NumSeq::KlarnerRado
Math::NumSeq::CollatzSteps, Math::NumSeq::JugglerSteps, Math::NumSeq::SternDiatomic, Math::NumSeq::NumAronson
Math::NumSeq::Kolakoski, Math::NumSeq::GolombSequence, Math::NumSeq::AsciiSelf
Math::NumSeq::Aronson, in the MathAronson dist
Math::Sequence and Math::Series, for symbolic recursive sequence definitions
HOME PAGE
http://user42.tuxfamily.org/mathnumseq/index.html
LICENSE
Copyright 2010, 2011 Kevin Ryde
MathNumSeq is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.
MathNumSeq is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with MathNumSeq. If not, see <http://www.gnu.org/licenses/>.