# Boost-Commit :

Subject: [Boost-commit] svn:boost r72900 - sandbox/SOC/2011/checks/libs/checks/doc
From: pierre.talbot.6114_at_[hidden]
Date: 2011-07-04 17:14:32

Date: 2011-07-04 17:14:31 EDT (Mon, 04 Jul 2011)
New Revision: 72900
URL: http://svn.boost.org/trac/boost/changeset/72900

Log:
Introduction of the modulus algorithms and repartition of the chapters
sandbox/SOC/2011/checks/libs/checks/doc/modulus.qbk (contents, props changed)

==============================================================================
--- (empty file)
+++ sandbox/SOC/2011/checks/libs/checks/doc/modulus.qbk 2011-07-04 17:14:31 EDT (Mon, 04 Jul 2011)
@@ -0,0 +1,19 @@
+[section:modulus Modular sum algorithms]
+
+A ['modular sum algorithm] makes the sum of a serie of digits modulo a number.
+The number obtained is called the ['check digit], in many codes it is added as the last digit.
+This rubbish algorithm detect all ['alteration] of one digit but doesn't detect a simple ['transposition] if the check digit is not altered.
+This is why even the most basic algorithms introduced the notion of ['weight]. The weight is the contribution of a number to the final sum.
+The following algorithms presented are the base of many, many codes and numbers in the world.
+We could describe a code and his check digit calculation with three characteristics : length, weigth and the modulus.
+So we could design a generic function for every modulus but we won't. It wouldn't be efficient and unnecessarily more complicated.
+The next parts will present the three different algorithms that we have designed.
+
+[h4 Luhn algorithm]
+
+The Luhn algorithm is well-known
+
+[h4 Modulus 10 algorithm]
+[h4 Modulus 11 algorithm]
+
+[endsect][/section:modulus Modular sum algorithms]
\ No newline at end of file