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Perl-Users Digest, Issue: 2909 Volume: 11

daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Tue Apr 13 06:09:23 2010

Date: Tue, 13 Apr 2010 03:09:07 -0700 (PDT)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)

Perl-Users Digest           Tue, 13 Apr 2010     Volume: 11 Number: 2909

Today's topics:
    Re: Matchtable sln@netherlands.com
    Re: Matchtable <boerni_s@bluewin.ch>
    Re: Net::SMTP errors <RedGrittyBrick@spamweary.invalid>
        Posting Guidelines for comp.lang.perl.misc ($Revision:  tadmc@seesig.invalid
        Question about Algorithm::Diff <dilbert1999@gmail.com>
    Re: Question about Algorithm::Diff <KBfoMe@realdomain.net>
    Re: Question about Algorithm::Diff <KBfoMe@realdomain.net>
    Re: Question about Algorithm::Diff <dilbert1999@gmail.com>
    Re: Question about Algorithm::Diff <dilbert1999@gmail.com>
    Re: software requirements again, take 483 (aka ? the Platypus)
        Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)

----------------------------------------------------------------------

Date: Mon, 12 Apr 2010 17:31:51 -0700
From: sln@netherlands.com
Subject: Re: Matchtable
Message-Id: <nbe7s512d30fe5at3b84jsu1gqac2uh9tb@4ax.com>

On Mon, 12 Apr 2010 10:41:21 +0200, Bernard <boerni_s@bluewin.ch> wrote:

>
>Hi all
>
>I already searched on Google, but unfortunately I don't know what it's 
>exactly called what I'm looking for.
>
>So what I'd like to do is to create a (text-)table and have a script to 
>find the best match. (Sorry... my english...)
>
>So here's an example:
>
>Table:
>#field1	|field2	|field3 |Output
>*	|*	|*	|Line1
>t*	|*	|*	|Line2
>t*	|x*	|*	|Line3
>*	|x*	|x*	|Line4
>
>
>Cases:
>
>Field 1: abc
>Field 2: abc
>Field 3: abc
>Should Match Line1
>
>Field 1: test
>Field 2: abc
>Field 3: abc
>Should match Line2
>
>Field 1: test
>Field 2: xyz
>Field 3: abc
>Should match Line3
>
>Field 1: test
>Field 2: xyz
>Field 3: xyz
>Should match Line4
>
>and so on...
>
>So I'm looking for a way to find the most exact match for given Input. 
>Is there a module that does this. If not how would you solve it? I know 
>I should include a some code of what I've already tried, but all the 
>ways I thought of, are just to complicated and I'm sure there must be an 
>easier way.
>
>So what I thought of is:
>- Build a Hash and then sort by length of key (field 1)... but that 
>wouldn't work for the 4th example.
>- Build 3 Hashes with field 1-3 as keys and sort again by length and 
>give some kind of rating to the matches (so if field 1 matches with a 
>String with a lenght of 3 Characters it will get 3 Points)
>
>Thank you very much in advance
>Bernard
>

One approach would be to "weight" the rows, then "weight" the columns
in that order with whatever criteria fits your needs.
Should only need to do it once (or when adding a new record).
Once weighted store it in a file.

-sln

---------------

c:\temp>perl aa.pl
6       |*      |x*     |x*     |Line4
3       |tt*    |x*     |*      |Line3.1
3       |tr*    |x*     |*      |Line3.03
3       |t*     |x*     |*      |Line3.02
3       |att*   |x*     |*      |Line3.0
3       |at*    |x*     |*      |Line3.22
3       |aat*   |x*     |*      |Line3.11
3       |aaab*  |x*     |*      |Line3.04
3       |aaa*   |xa*    |*      |Line3.211
3       |aaa*   |x*     |*      |Line3.21
3       |aa*    |x*     |*      |Line3.2
3       |a*     |x*     |*      |Line3.01
1       |t*     |*      |*      |Line2
0       |*      |*      |*      |Line1

c:\temp>

use strict;
use warnings;

my @template = ();

while (<DATA>)
{
	chomp;
	next if /^\s*$/;
	my ($val,$cnt) = (0,0);

	## Weight cross fields
	 for my $fld (split /\t\|/, $_)
	 {
		$val += 2**$cnt if ($fld =~ /[^*]/);
		$cnt++;
		last if $cnt>2;
	 }
	 push @template, "$val\t|".$_;
}

## Weight within fields 
 @template = sort {
	  my ($b0,$b1,$b2,$b3) = split /\t\|/, $b;
	  my ($a0,$a1,$a2,$a3) = split /\t\|/, $a;
	  $b0 <=> $a0 ||
	  $b1 cmp $a1 ||
	  $b2 cmp $a2 ||
	  $b3 cmp $a3
	} @template;

for my $str (@template) {
	print "$str\n";
}
__DATA__

at*	|x*	|*	|Line3.22
aaab*	|x*	|*	|Line3.04
*	|*	|*	|Line1
t*	|*	|*	|Line2
aaa*	|x*	|*	|Line3.21
tt*	|x*	|*	|Line3.1
*	|x*	|x*	|Line4
att*	|x*	|*	|Line3.0
a*	|x*	|*	|Line3.01
t*	|x*	|*	|Line3.02
tr*	|x*	|*	|Line3.03
aat*	|x*	|*	|Line3.11
aa*	|x*	|*	|Line3.2
aaa*	|xa*	|*	|Line3.211



------------------------------

Date: Tue, 13 Apr 2010 10:00:50 +0200
From: Bernard <boerni_s@bluewin.ch>
Subject: Re: Matchtable
Message-Id: <hq18bg$qen$1@speranza.aioe.org>

Hi all

Thank you very much for your responses.

I found a solution that works for me in the meantime.
Bernard

Table looks like this:
#Hostname| Subsystem | Probe | User Tag | Group
*        | System*   | nt*   | *        | NT_Group
asdf*    | System*   | nt*   | *        | NT_Group_APAC
us*      | pr*       | Misc* | *        | US_Servicedesk
us-*     | *         | *     | *        | US_Network
*        | *         | *     | *        | Default_Group

Script:
#!perl -w
use strict;

my $table_file = './io/matchtst.lst';

my $table = read_table($table_file) or die;

my $group = find_match( $table,
             'us-asdf',
             'printer',
             'Domino',
             '') or die;

print "Group is $group\n";
exit 0;


#---- Subroutinen ----#

sub read_table {
   my $table_file = shift;

   my $table;

   open(IN, $table_file) or die "cant read $table_file: $!\n";

   while(<IN>) {
     chomp;
     next if (/^\#/ or ! $_);

     s/\*/\.\*/g;

     my ($field1, $field2, $field3, $field4, $output) = split(/\s+\|\s+/);
     my $key = join('~~', ($field1, $field2, $field3, $field4));

     $table->{$key}->{'field1'} = $field1;
     $table->{$key}->{'field2'} = $field2;
     $table->{$key}->{'field3'} = $field3;
     $table->{$key}->{'field4'} = $field4;
     $table->{$key}->{'output'} = $output;
   }

   close IN;

   return $table;
}

sub find_match {
   my %fields;
   my %score;

   my $table = shift;

   my $field1 = shift;
   my $field2 = shift;
   my $field3 = shift;
   my $field4 = shift;

   foreach my $key(sort {length($b) <=> length($a)} keys %$table) {

     if ($field1 =~ /$table->{$key}->{'field1'}/ and
         $field2 =~ /$table->{$key}->{'field2'}/ and
         $field3 =~ /$table->{$key}->{'field3'}/ and
         $field4 =~ /$table->{$key}->{'field4'}/) {

           if (! $score{'score'} or ($score{'score'} < length($key))) {
           $score{'score'} = length($key);
           $score{'pattern'} = $key;
         }
     }
   }

   return $table->{$score{'pattern'}}->{'output'};

}







------------------------------

Date: Tue, 13 Apr 2010 09:55:24 +0100
From: RedGrittyBrick <RedGrittyBrick@spamweary.invalid>
Subject: Re: Net::SMTP errors
Message-Id: <4bc4317f$0$2492$db0fefd9@news.zen.co.uk>

On 12/04/2010 19:31, david.karr wrote:
> I'm putting some code in an existing script to send an email
> notification. I've read the Net::SMTP CPAN page.  I'm not doing
> anything complicated. I appear to be getting SMTP errors, but I don't
> understand how to fix this.
>
> The method I wrote to send the message is the following (some data
> elided):
>
> sub sendUpdateNotification($$$) {
>      my ($message, $mailhost, $maildest) = @_;
>      my $smtp = Net::SMTP->new($mailhost,
> 			      Hello =>  "<mydomain>",
> 	                      Debug =>  1);
>
>      print "domain[" . $smtp->domain . "] maildest[" . $maildest . "]
> \n";
>      print "message[" . $message . "]\n";
>
>      $smtp->mail($ENV{USER});

According to http://search.cpan.org/~gbarr/libnet-1.22/Net/SMTP.pm the 
parameters for the mail() method are mail ( ADDRESS [, OPTIONS] ) where 
ADDRESS is the address of the sender.

$ENV{USER} is unlikely to be an email address.



>      $smtp->to($maildest, {Notify =>  ['SUCCESS','FAILURE','DELAY']});
>      $smtp->data($message);
>
>      $smtp->quit;
> }
>
> The output I see is the following (some fields elided):
>
> Net::SMTP>>>  Net::SMTP(2.31)
> Net::SMTP>>>    Net::Cmd(2.29)
> Net::SMTP>>>      Exporter(5.62)
> Net::SMTP>>>    IO::Socket::INET(1.31)
> Net::SMTP>>>      IO::Socket(1.30_01)
> Net::SMTP>>>        IO::Handle(1.27)
> Net::SMTP=GLOB(0x10b822c0)<<<  220<our smtp host>  ESMTP Sendmail
> 8.14.2/8.14.2; Mon, 12 Apr 2010 11:22:16 -0700
> Net::SMTP=GLOB(0x10b822c0)>>>  EHLO att.com
> Net::SMTP=GLOB(0x10b822c0)<<<  250-<our smtp host>  Hello<myhost>
> [<myip>], pleased to meet you
> Net::SMTP=GLOB(0x10b822c0)<<<  250-ENHANCEDSTATUSCODES
> Net::SMTP=GLOB(0x10b822c0)<<<  250-PIPELINING
> Net::SMTP=GLOB(0x10b822c0)<<<  250-8BITMIME
> Net::SMTP=GLOB(0x10b822c0)<<<  250-SIZE 16000000
> Net::SMTP=GLOB(0x10b822c0)<<<  250-DSN
> Net::SMTP=GLOB(0x10b822c0)<<<  250-ETRN
> Net::SMTP=GLOB(0x10b822c0)<<<  250-DELIVERBY
> Net::SMTP=GLOB(0x10b822c0)<<<  250 HELP
> Net::SMTP=GLOB(0x10b822c0)>>>  MAIL FROM:<<myid>>
> Net::SMTP=GLOB(0x10b822c0)<<<  553 5.5.4<<myid>>... Domain name
> required for sender address<myid>

A domain name is needed in the sender's mail address.


> Net::SMTP=GLOB(0x10b822c0)>>>  RCPT TO:<<myid>@<mydomain>>
> NOTIFY=SUCCESS,FAILURE,DELAY
> Net::SMTP=GLOB(0x10b822c0)<<<  503 5.0.0 Need MAIL before RCPT

You haven't sent a valid MAIL command.


> Net::SMTP=GLOB(0x10b822c0)>>>  DATA
> Net::SMTP=GLOB(0x10b822c0)<<<  503 5.0.0 Need MAIL command
> Net::SMTP=GLOB(0x10b822c0)>>>  QUIT
> Net::SMTP=GLOB(0x10b822c0)<<<  221 2.0.0<our smtp host>  closing
> connection


-- 
RGB


------------------------------

Date: Tue, 13 Apr 2010 02:14:16 -0500
From: tadmc@seesig.invalid
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.9 $)
Message-Id: <kYKdnVFm6bZVhFnWnZ2dnUVZ_gudnZ2d@giganews.com>

Outline
   Before posting to comp.lang.perl.misc
      Must
       - Check the Perl Frequently Asked Questions (FAQ)
       - Check the other standard Perl docs (*.pod)
      Really Really Should
       - Lurk for a while before posting
       - Search a Usenet archive
      If You Like
       - Check Other Resources
   Posting to comp.lang.perl.misc
      Is there a better place to ask your question?
       - Question should be about Perl, not about the application area
      How to participate (post) in the clpmisc community
       - Carefully choose the contents of your Subject header
       - Use an effective followup style
       - Speak Perl rather than English, when possible
       - Ask perl to help you
       - Do not re-type Perl code
       - Provide enough information
       - Do not provide too much information
       - Do not post binaries, HTML, or MIME
      Social faux pas to avoid
       - Asking a Frequently Asked Question
       - Asking a question easily answered by a cursory doc search
       - Asking for emailed answers
       - Beware of saying "doesn't work"
       - Sending a "stealth" Cc copy
      Be extra cautious when you get upset
       - Count to ten before composing a followup when you are upset
       - Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------

Posting Guidelines for comp.lang.perl.misc ($Revision: 1.9 $)
    This newsgroup, commonly called clpmisc, is a technical newsgroup
    intended to be used for discussion of Perl related issues (except job
    postings), whether it be comments or questions.

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        http://www.catb.org/~esr/faqs/smart-questions.html

    describes how to get answers from technical people in general.

    This article describes things that you should, and should not, do to
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     http://www.rehabitation.com/clpmisc.shtml

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Before posting to comp.lang.perl.misc
  Must
    This section describes things that you *must* do before posting to
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    The perl distribution includes documentation that is copied to your hard
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    Check the Perl Frequently Asked Questions (FAQ)
        Checking the FAQ before posting is required in Big 8 newsgroups in
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        You can use the "-q" switch with perldoc to do a word search of the
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    Check the other standard Perl docs (*.pod)
        The perl distribution comes with much more documentation than is
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  Really Really Should
    This section describes things that you *really should* do before posting
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    Lurk for a while before posting
        This is very important and expected in all newsgroups. Lurking means
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    Search a Usenet archive
        There are tens of thousands of Perl programmers. It is very likely
        that your question has already been asked (and answered). See if you
        can find where it has already been answered.

        One such searchable archive is:

         http://groups.google.com/advanced_search

  If You Like
    This section describes things that you *can* do before posting to
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    Check Other Resources
        You may want to check in books or on web sites to see if you can
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        But you need to consider the source of such information: there are a
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Posting to comp.lang.perl.misc
    There can be 200 messages in clpmisc in a single day. Nobody is going to
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    Your post is in competition with 199 other posts. You need to "win"
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  Is there a better place to ask your question?
    Question should be about Perl, not about the application area
        It can be difficult to separate out where your problem really is,
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        Being able to "partition" a problem is an essential skill for
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        It should be understood that you may not know that the root of your
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  How to participate (post) in the clpmisc community
    Carefully choose the contents of your Subject header
        You have 40 precious characters of Subject to win out and be one of
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         http://web.presby.edu/~nnqadmin/nnq/nquote.html

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    Do not re-type Perl code
        Use copy/paste or your editor's "import" function rather than
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    Provide enough information
        If you do the things in this item, you will have an Extremely Good
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        These features are a really big bonus toward your question winning
        out over all of the other posts that you are competing with.

        First make a short (less than 20-30 lines) and *complete* program
        that illustrates the problem you are having. People should be able
        to run your program by copy/pasting the code from your article. (You
        will find that doing this step very often reveals your problem
        directly. Leading to an answer much more quickly and reliably than
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        Describe *precisely* the input to your program. Also provide example
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        Describe how you want the output to be different from what you are
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    Do not provide too much information
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  Social faux pas to avoid
    The first two below are symptoms of lots of FAQ asking here in clpmisc.
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        It should be understood that you may have missed the applicable FAQ
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        If folks think you have not even tried the obvious step of reading
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        Ask the question here, get the answer here (maybe).

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        This is a "red flag" phrase. If you find yourself writing that,
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    Sending a "stealth" Cc copy
        A "stealth Cc" is when you both email and post a reply without
        indicating *in the body* that you are doing so.

  Be extra cautious when you get upset
    Count to ten before composing a followup when you are upset
        This is recommended in all Usenet newsgroups. Here in clpmisc, most
        flaming sub-threads are not about any feature of Perl at all! They
        are most often for what was seen as a breach of netiquette. If you
        have lurked for a bit, then you will know what is expected and won't
        make such posts in the first place.

        But if you get upset, wait a while before writing your followup. I
        recommend waiting at least 30 minutes.

    Count to ten after composing and before posting when you are upset
        After you have written your followup, wait *another* 30 minutes
        before committing yourself by posting it. You cannot take it back
        once it has been said.

AUTHOR
    Tad McClellan and many others on the comp.lang.perl.misc newsgroup.

-- 
Tad McClellan
email: perl -le "print scalar reverse qq/moc.liamg\100cm.j.dat/"
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.


------------------------------

Date: Mon, 12 Apr 2010 13:24:54 -0700 (PDT)
From: Dilbert <dilbert1999@gmail.com>
Subject: Question about Algorithm::Diff
Message-Id: <a954b0be-49b1-4e6c-8811-61aa874c8649@c21g2000yqk.googlegroups.com>

I have a question about the Perl Module Algorithm::Diff.

I want to use Algorithm::Diff to calculate the diff of the two
sequences "ab" and "a1bab", the "LCS" (the "Longest Common Sequence")
is a length of 2.

Theoretically there are 3 solutions with LCS = 2:

Solution 1:
---ab
a1bab

Solution 2:
a-b--
a1bab

Solution 3:
a---b
a1bab

I understand that any of those 3 solutions could be returned by
Algorithm::Diff, but I would argue that solution 1 is "better" than
solution 2 or 3, because solution 1 changes only once between '-' and
[ab], whereas solution 2 and 3 change more than once between '-' and
[ab].

This is my Perl program:

use strict;
use warnings;
use 5.010;
use Algorithm::Diff;
use Data::Dumper;
my @old = split //, 'ab';
my @new = split //, 'a1bab';
my $d = Algorithm::Diff::sdiff(\@old, \@new);
my $line = Dumper($d);
$line =~ s{\s}''xmsg;
say $line;

The output is
$VAR1=[['u','a','a'],['+','','1'],['+','','b'],['+','','a'],
['u','b','b']];

This is in fact Solution 3:
a---b
a1bab

How can I teach Algorithm::Diff to choose Solution 1 (the best of the
3 possibilities) ?


------------------------------

Date: Tue, 13 Apr 2010 02:01:16 -0500
From: "Kyle T. Jones" <KBfoMe@realdomain.net>
Subject: Re: Question about Algorithm::Diff
Message-Id: <hq14sn$rkj$1@news.eternal-september.org>

Dilbert wrote:
> I have a question about the Perl Module Algorithm::Diff.
> 
> I want to use Algorithm::Diff to calculate the diff of the two
> sequences "ab" and "a1bab", the "LCS" (the "Longest Common Sequence")
> is a length of 2.
> 
> Theoretically there are 3 solutions with LCS = 2:
> 
> Solution 1:
> ---ab
> a1bab
> 
> Solution 2:
> a-b--
> a1bab
> 
> Solution 3:
> a---b
> a1bab
> 

There is only one LCS solution - 'ab'. You're making too much of it and 
you don't get to say there are 3 solutions with LCS = 2 (as if you were 
assigning 2, and LCS=3 or LCS=1 were possible with the data you 
provide), there is just *the* LCS solution, which, in this case, happens 
to be 'ab'.

> I understand that any of those 3 solutions could be returned by
> Algorithm::Diff, but I would argue that solution 1 is "better" than
> solution 2 or 3, because solution 1 changes only once between '-' and
> [ab], whereas solution 2 and 3 change more than once between '-' and
> [ab].
> 
> This is my Perl program:
> 
> use strict;
> use warnings;
> use 5.010;
> use Algorithm::Diff;
> use Data::Dumper;
> my @old = split //, 'ab';
> my @new = split //, 'a1bab';
> my $d = Algorithm::Diff::sdiff(\@old, \@new);
> my $line = Dumper($d);
> $line =~ s{\s}''xmsg;
> say $line;
> 
> The output is
> $VAR1=[['u','a','a'],['+','','1'],['+','','b'],['+','','a'],
> ['u','b','b']];
> 
> This is in fact Solution 3:
> a---b
> a1bab
> 

No, this is the smallest set of instructions for turning the first 
sequence into the second sequence (same as diff), with what some find to 
be an easier to read "side by side" format:

(unchanged, was 'a', stays 'a')
(add, was nothing(''), adds '1')
(add, was nothing(''), adds 'b')
(add, was nothing(''), adds 'a')
(unchanged, was 'b', stays 'b')


The same set of instructions in diff would just be:

[
	['+', 1, '1'],
	['+', 2, 'b'],
	['+', 3, 'a'],
]

> How can I teach Algorithm::Diff to choose Solution 1 (the best of the
> 3 possibilities) ?

That question doesn't make a lot of sense (to me).

http://search.cpan.org/dist/Algorithm-Diff/lib/Algorithm/Diff.pm

Cheers.


------------------------------

Date: Tue, 13 Apr 2010 02:17:59 -0500
From: "Kyle T. Jones" <KBfoMe@realdomain.net>
Subject: Re: Question about Algorithm::Diff
Message-Id: <hq15s3$s8$1@news.eternal-september.org>

Dilbert wrote:

I may have misunderstood what you were asking a second ago... let me try 
again (including diff for each of your three solutions):

> I have a question about the Perl Module Algorithm::Diff.
> 
> I want to use Algorithm::Diff to calculate the diff of the two
> sequences "ab" and "a1bab", the "LCS" (the "Longest Common Sequence")
> is a length of 2.
> 
> Theoretically there are 3 solutions with LCS = 2:
> 
> Solution 1:
> ---ab
> a1bab
> 


[
     ['+', 0, 'a'],
     ['+', 1, '1'],
     ['+', 2, 'b'],
]

> Solution 2:
> a-b--
> a1bab
> 


[
     ['+', 1, '1'],
     ['+', 3, 'a'],
     ['+', 4, 'b'],
]

> Solution 3:
> a---b
> a1bab
>


[
     ['+', 1, '1'],
     ['+', 2, 'b'],
     ['+', 3, 'a'],
]

> 
> How can I teach Algorithm::Diff to choose Solution 1 (the best of the
> 3 possibilities) ?

Why are any of the three better?  Any way you crack this nut, the 
smallest sequence of operations to turn ab into a1bab involves three 
adds... so I'm confused as to why you pick one as "best"?

Cheers.


------------------------------

Date: Tue, 13 Apr 2010 02:58:04 -0700 (PDT)
From: Dilbert <dilbert1999@gmail.com>
Subject: Re: Question about Algorithm::Diff
Message-Id: <7e1c5208-bee3-4223-b960-04086b718960@y14g2000yqm.googlegroups.com>

On 13 avr, 09:17, "Kyle T. Jones" <KBf...@realdomain.net> wrote:
> Dilbert wrote:
> > How can I teach Algorithm::Diff to choose Solution 1 (the best of the
> > 3 possibilities) ?
>
> Why are any of the three better? =A0Any way you crack this nut, the
> smallest sequence of operations to turn ab into a1bab involves three
> adds... so I'm confused as to why you pick one as "best"?

Let me try a more realistic example:

use strict;
use warnings;
use 5.010;
use Algorithm::Diff;
use Data::Dumper;
my @old =3D split //, 'ab';
my @new =3D split //, 'Show manual contribution: ab :This word can be
displayed';
my $d =3D Algorithm::Diff::sdiff(\@old, \@new);
my $line =3D Dumper($d);
$line =3D~ s{\s}''xmsg;
say $line;

The output alignment (#al1) is:

-a-----------b---------------------------
manual contribution: ab :can be displayed

But what I want is (#al2):

---------------------ab------------------
manual contribution: ab :can be displayed

Why ?

Because, in case I have more than one optimal solution (and this is
the case here), I want to consider not only the value of a character
('a' eq 'a' and 'b' eq 'b'), but also the context each character is
in.

the 'a' in @old has context: {left =3D> 'start', right =3D> 'b'}
the 'b' in @old has context: {left =3D> 'a', right =3D> 'end'}

the 'a' in @new (#al1) context: {left =3D> 'm', right =3D> 'n'}
the 'b' in @new (#al1) context: {left =3D> 'i', right =3D> 'u'}

the 'a' in @new (#al2) context: {left =3D> ' ', right =3D> 'b'}
the 'b' in @new (#al2) context: {left =3D> 'a', right =3D> ' '}

It can easily be seen that @old and @new(#al1) have no context in
common

Whereas @old and @new(#al2) have two context matches, that is
  @old('a')->right eq @new(#al2)'a'->right
  @old('b')->left eq @new(#al2)'a'->left

That's why I prefer @new (#al2) over @new (#al1)


------------------------------

Date: Tue, 13 Apr 2010 03:08:04 -0700 (PDT)
From: Dilbert <dilbert1999@gmail.com>
Subject: Re: Question about Algorithm::Diff
Message-Id: <7f1cb764-c1f8-4e25-b4ae-8f3f1e913265@k33g2000yqc.googlegroups.com>

On 13 avr, 11:58, Dilbert <dilbert1...@gmail.com> wrote:
> my @new =3D split //, 'Show manual contribution: ab :This word can be
> displayed';

That should be...

my @new =3D split //, 'manual contribution: ab :can be displayed';

> Whereas @old and @new(#al2) have two context matches, that is
> =A0 @old('a')->right eq @new(#al2)'a'->right
> =A0 @old('b')->left eq @new(#al2)'a'->left

in the last line, replace
  "...@new(#al2)'a'->left..." by
  "...@new(#al2)'b'->left..."


------------------------------

Date: 12 Apr 2010 20:26:31 GMT
From: "David Formosa (aka ? the Platypus)" <dformosa@usyd.edu.au>
Subject: Re: software requirements again, take 483
Message-Id: <4bc381f6$0$27783$c3e8da3@news.astraweb.com>

On Mon, 05 Apr 2010 15:44:04 -0700, Jürgen Exner <jurgenex@hotmail.com> wrote:
[...]
> And I cannot imagine how email or the Internet or Usenet would work
> without any written specs and protocols.

Usenet and email both where cases where existing protocols where
documented after they where implimented rather then the other way
around.


------------------------------

Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin) 
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>


Administrivia:

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------------------------------
End of Perl-Users Digest V11 Issue 2909
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