LetterCounter Python module

Fun with letters

Classes

LetterIterator

An Iterator that counts from A → Z, AA → AZ, BA → ... → ZZ, AAA → ...

It supports start value, end value, step, and any alphabet.
>>> from lettercounter import LetterIterator
>>> li = LetterIterator()
>>> li.next(), li.next(), li.next()
('A', 'B', 'C')
>>> for l in LetterIterator('A', 'BA'):
...     print l,
...
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z AA AB AC AD AE AF AG AH AI AJ AK AL AM AN AO AP AQ AR AS AT AU AV AW AX AY AZ BA
>>> for l in LetterIterator('AA', 'BA', 2):
...     print l,
...
AA AC AE AG AI AK AM AO AQ AS AU AW AY BA
>>> for l in LetterIterator('aaa', 'ccc', letters='abc'):
...     print l,
...
aaa aab aac aba abb abc aca acb acc baa bab bac bba bbb bbc bca bcb bcc caa cab cac cba cbb cbc cca ccb ccc

LetterCounter

Most numbers written in bases higher than 10 use letters to represent numbers higher than ten. The most common such case is hexadecimal, which uses the digits [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F].

Bases of up to 36 (0-9 and 26 letters) can be represented like this, but I wanted a system that counted upwards from A, not 0.

Here are a couple of lines of examples on how this class can be used. Note that 'A' is equivalent to zero, not one.

>>> from lettercounter import LetterCounter
>>> lc = LetterCounter()
>>> lc
LetterCounter("")
>>> print lc

>>> lc = LetterCounter('FJEIO')
>>> print lc
FJEIO
>>> int(lc)
2445990
>>> lc2 = LetterCounter(LetterCounter.fromInt(20))
>>> lc2
LetterCounter("U")
>>> result = lc + lc2
>>> result
LetterCounter("FJEJI")
>>> result / 4
LetterCounter("BIUPI")
>>> int(LetterCounter(LetterCounter.fromInt(0)))
0
>>> print LetterCounter('AAAAF')
AAAAF
>>> print LetterCounter('AAAAF').unpad()
F
>>> print LetterCounter('FOO').pad(5)
AAFOO

Download

The module is released under the GNU GPL.
Install with setuptools:

$ easy_install -f http://www.nivan.net/nickmurdoch/projects/lettercounter.shtml LetterCounter

Current version

LetterCounter 0.3.1 - Added __cmp__ method for LetterIterator

Older versions

LetterCounter 0.3 - Added LetterIterator
LetterCounter 0.2 - First egg distribution

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Last Modified: Monday, 20-Aug-2007 10:33:51 BST