Writing Donald E. Knuth based code in Python, cont'd

Juhani Ylikoski antti.ylikoski at elisanet.fi
Tue Nov 13 08:52:34 CET 2012

There were there two (2) bugs in the code that I posted.  Thanks anyway.

A. J. Y.

"Vincent Vande Vyvre"  kirjoitti 
viestissä:mailman.3596.1352758176.27098.python-list at python.org...

Le 12/11/12 22:02, Juhani Ylikoski a écrit :
> Following comes a working, debugged Python program which computes the
> permutations of the integers 1, 2, 3 - n after Donald E. Knuth.  I
> present it as an example of writing straightforward, easy Knuth-based
> code in a language with no GOTO statement.
> The Python program has been written after the DFA construct I
> previously discussed in this newsgroup, and after Knuth's discussion
> of the solution of the problem; and according the (very good)
> discussions in this newsgroup.  To my opinion, it no more is a "crow's
> nest" as they say in Finnish.
> This program was needed for a real problem, namely computing optimal
> tournament tables for a Bughouse (Tandem) chess tournament.  See
> http://en.wikipedia.org/wiki/Bughouse_chess
> Knuth became criticized in the newsgroup; but to my opinion his books
> are still useful and nontrivially needed.
> ---
> yours sincerely, Antti J Ylikoski
> Helsinki, Finland
> PhD student in the Aalto University

One comment in:

   def E1(self): # Phase 1 in Knuth's text
       self.app = self.listofPerm.append(self.a[1:self.n+1])
       return self.E2 # next state: E2

append() return None and self.app is no longer used in the code.

Missing something ?

Vincent V.V.
Oqapy <https://launchpad.net/oqapy> . Qarte
<https://launchpad.net/qarte> . PaQager <https://launchpad.net/paqager> 

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