The if-else cases in lsqr.py were not exhaustive. They become exhaustive by changing ab > aa to ab >= aa.
From: Dmitriy Morozov <dmitriy@mrzv.org>
Date: Sat, 20 Dec 2008 21:24:59
State: new
Subject: Add field arithmetic
Message-Id: <f6496b3e37275888-0-artemis@rufus>
category: functionality
Add support for field arithmetic (i.e., not only Z_2 field as it is now).
However, make sure that there is a specialization of ChainWrapper<C>::add() for
Z_2 field (since it can be made much more efficient both in terms of space and
time).