I can see (I think) how you transform

a a b
to
a a -
and 
a a b
b b c

[download]

to
b b b
and
b b c
c d d

[download]

to - d d
but the rule I intuit for those doesn't work for the transformation of 
b b c
c d d

[download]

to
c - c

CODE TAGS...

<c> ... data here
(even multiline data)... </c>
might help us to understand how you get from the source of the list to the output; that is, by what rule(s) are you doing the tranformations?

or is it just too late in the evening for me to understand?


Questions containing the words "doesn't work" (or their moral equivalent) will usually get a downvote from me unless accompanied by:
  1. code
  2. verbatim error and/or warning messages
  3. a coherent explanation of what "doesn't work actually means.

In reply to Re: Comparing and Aligning arrays by ww
in thread Comparing and Aligning arrays by abd

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