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Re: linear programming

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* eric, on 20.06.2011 05:53:
> Dear c++ or advanced computer scienctist or mathmatician:
>    on the book(Introduction to Algorithms 3rd ed) page 851, chapter 29
> Linear Programming
> I ask one of that book's author:
> -----------------------------------------------
>     dear thomas:
>
>    the the end of that page
>
>   if a linear program has some feasible solutions but does not have a
>   finite optimal objective value, we say that the linear program is
>   unbounded
>
>   but
>   you want us to prove in Exercise 29.1-9
>   to show
>   that a linear program can have a finite optimal objective value even
> if
>   the feasible region is not bounded
>
>   which is very unlogical for me
>
>   looking to hear from you soon
>   Eric
>
> ------------------------------------------------------------------
>
> Eric, you'll have to think outside the box just a little bit.  It may
> seem illogical, but there's a simple solution.
>
> Tom Cormen
> Professor and Chair
> Dartmouth College Department of Computer Science
> http://www.cs.dartmouth.edu/~thc/
> -----------------------------------------------------
> but I still not figure out
> plz give hint/suggestion/advice, thank your help/effort/time a lot in
> advance, Eric

Let

   A = does not have finite objective value
   B = is unbounded

One statement you're quoting is that A implies B.
This means that in every case where A is true, B will necessarily be true.
Another is that B does not imply A.
This means that in some cases where B is true, A is not true.

For example, if you're out in the rain without any protection, then you get wet.
And in some cases when you get wet, you are not out in the rain without protection.


Cheers & hth., and please post to a relevant group next time!,

- Alf

-- 
blog at <url: http://alfps.wordpress.com>

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linear programming eric <cneric12lin0@gmail.com> - 2011-06-19 20:53 -0700
  Re: linear programming "Alf P. Steinbach /Usenet" <alf.p.steinbach+usenet@gmail.com> - 2011-06-20 08:36 +0200
    Re: linear programming eric <cneric12lin0@gmail.com> - 2011-06-20 00:58 -0700
      Re: linear programming "Alf P. Steinbach /Usenet" <alf.p.steinbach+usenet@gmail.com> - 2011-06-20 11:38 +0200
    Re: linear programming gwowen <gwowen@gmail.com> - 2011-06-20 03:07 -0700
      Re: linear programming "Alf P. Steinbach /Usenet" <alf.p.steinbach+usenet@gmail.com> - 2011-06-20 14:09 +0200
        Re: linear programming gwowen <gwowen@gmail.com> - 2011-06-20 05:59 -0700
          Re: linear programming gwowen <gwowen@gmail.com> - 2011-06-20 06:03 -0700
          Re: linear programming Martijn van Buul <pino@dohd.org> - 2011-06-20 15:13 +0000
            Re: linear programming gwowen <gwowen@gmail.com> - 2011-06-20 08:38 -0700
              Re: linear programming Martijn van Buul <pino@dohd.org> - 2011-06-20 19:24 +0000
                Re: linear programming Gareth Owen <gwowen@gmail.com> - 2011-06-21 06:30 +0100
                Re: linear programming gwowen <gwowen@gmail.com> - 2011-06-21 00:17 -0700
            [OT] Re: linear programming Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-06-20 21:56 +0200
              Re: linear programming eric <cneric12lin0@gmail.com> - 2011-06-20 17:27 -0700
  Re: linear programming "Paul" <pchristor@yahoo.co.uk> - 2011-06-20 11:17 +0100
  Re: linear programming gwowen <gwowen@gmail.com> - 2011-06-20 03:07 -0700
  [OT] Re: linear programming Kai-Uwe Bux <jkherciueh@gmx.net> - 2011-06-20 19:38 +0200

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