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		<title>Holroyd: Created page with 'Alexander Holroyd holroyd at math.ubc.ca Wed Sep 29 12:35:12 BST 2010  Here is an idea for an automated method for analysing the plans.  For each pair of plans in the list (ie a …'</title>
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		<summary type="html">&lt;p&gt;Created page with &amp;#039;Alexander Holroyd holroyd at math.ubc.ca Wed Sep 29 12:35:12 BST 2010  Here is an idea for an automated method for analysing the plans.  For each pair of plans in the list (ie a …&amp;#039;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;Alexander Holroyd holroyd at math.ubc.ca&lt;br /&gt;
Wed Sep 29 12:35:12 BST 2010&lt;br /&gt;
&lt;br /&gt;
Here is an idea for an automated method for analysing the plans.&lt;br /&gt;
&lt;br /&gt;
For each pair of plans in the list (ie a few million pairs), do the &lt;br /&gt;
following.  &amp;quot;Rotate&amp;quot; one of the pair through all 60 possible starting &lt;br /&gt;
rows.  (Your plans are already in standard form, aren't they?)  For each &lt;br /&gt;
such rotation, compare the two plans.  Specifically, look to see whether &lt;br /&gt;
the two plans are identical except that one is obtained from the other by &lt;br /&gt;
replacing some set of leads all of method X with all method Y.  If so, say &lt;br /&gt;
that there is a &amp;quot;simple splice&amp;quot; between the two plans.  The simple splice &lt;br /&gt;
itself may be described by saying what methods X and Y are, and what the &lt;br /&gt;
set of leads is, in &amp;quot;standard form&amp;quot; (i.e. rotated to it's smallest version &lt;br /&gt;
in lexicographic order).&lt;br /&gt;
&lt;br /&gt;
After this is done for all pairs, the set of simple splices that arise had &lt;br /&gt;
better be what exactly we expect, i.e. things like &amp;quot;2 copies of the &lt;br /&gt;
Cambride-Beverley 6-lead splice&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
We now have a graph, whose vertices (nodes) are the plans, and whose edges &lt;br /&gt;
(links) are the simple splices.  Break this graph up into its connected &lt;br /&gt;
components, or &amp;quot;clusters&amp;quot;.  Each cluster is a group of plans all of which &lt;br /&gt;
communicate with each other via simple splices.&lt;br /&gt;
&lt;br /&gt;
For a start I would like to know how many clusters there are.&lt;br /&gt;
&lt;br /&gt;
Now we want to analyse the clusters.  Any cluster that contains a &lt;br /&gt;
single-method extent can be removed from the game, because these we &lt;br /&gt;
(hopefully) completely understand.  For the others, it would be desirable &lt;br /&gt;
to nominate a &amp;quot;standard representative&amp;quot; plan from each cluster - the basic &lt;br /&gt;
plan which then gets embelished with various simple splices to form the &lt;br /&gt;
other members of the cluster.  I'm not sure whether there is a canonical &lt;br /&gt;
way to do this in general, but one natural thing that springs to mind is &lt;br /&gt;
to list, for each cluster, the plans that have the smallest number of &lt;br /&gt;
methods, and see by hand which of these (if there is more than one) is the &lt;br /&gt;
most &amp;quot;natural&amp;quot;.&lt;br /&gt;
&lt;br /&gt;
Then one can summarize the whole thing by listing, for each cluster, its &lt;br /&gt;
standard representative, and the list of all simple splices it involves. &lt;br /&gt;
I suspect such a list would be quite manageable.&lt;br /&gt;
&lt;br /&gt;
----&lt;br /&gt;
&lt;br /&gt;
Richard Smith richard at ex-parrot.com&lt;br /&gt;
Wed Sep 29 19:57:24 BST 2010&lt;br /&gt;
&lt;br /&gt;
There are 506 connected components of which 14 are simple. &lt;br /&gt;
The simple components contain the methods:&lt;br /&gt;
&lt;br /&gt;
  1.  Sg&lt;br /&gt;
  2.  Nm So C3 C2 Pn&lt;br /&gt;
  3.  Nw Mo Ak Ct Mu Ch Av Ca Ke Ce Cd Sw Va Li Co Cc We Lo&lt;br /&gt;
      Cu Cx Bn Pv Bt Le Md Mp C1 Cl Nb Wh Gl Fo Ml By Pm Ed&lt;br /&gt;
      Kh Ww Lu Cz Cy Bh Os Bw Wf&lt;br /&gt;
  4.  Qu Sn Ti Sh Tr Km&lt;br /&gt;
  5.  Kt&lt;br /&gt;
  6.  Bl Wk&lt;br /&gt;
  7.  Fr Cg&lt;br /&gt;
  8.  Cj Nl&lt;br /&gt;
  9.  Du Yo Su He Bv Bk Cm Pr Ip Nf Bs Wa&lt;br /&gt;
  10. Bu&lt;br /&gt;
  11. Es Cv&lt;br /&gt;
  12. Rc Bz&lt;br /&gt;
  13. Bm Bc El Cr Wm St Lf Ro Sa Wo Te Ev Po Dt Ck Wt Di Ms&lt;br /&gt;
      Do Dn Pe Wl Bg Kn Rs Ba Cs Fg Sk Ey Bp Wv Bo Hu Ki Lv&lt;br /&gt;
      Cn Ri Dk Cf Ny Oc Ci Ks Ls Sd Ox No Ne Ab Ws Ad Ma Br&lt;br /&gt;
      Ta Hm Ol Cb Ng Wi Cw Ns Sl Wr&lt;br /&gt;
  14. Be Me&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
The full list of plans grouped into clusters is here:&lt;br /&gt;
&lt;br /&gt;
http://ex-parrot.com/~richard/minor/147/plans-in-clusters.txt&lt;/div&gt;</summary>
		<author><name>Holroyd</name></author>
		
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