Re: [Help-glpk] cspsol webapp

[Meketon, Marc]

Solving the knapsack subproblem of the CSP is typically best done using dynamic programming and not using MIP.  You may wish to consider that.

 

The best dynamic programming algorithm I have found is in the book by Kellerer, Pferschy and Pisinger [2004, Springer-Verlag, ISBN 3-540-40286-1].

 

I had implemented a related knapsack problem using that book.  In this case the cost and the weight of the objects were the same (some folks call this the subset-sum problem), and later on I posted it as an answer in stack overflow (http://stackoverflow.com/questions/18066624/maximum-sum-of-a-subset-of-size-k-with-sum-less-than-m/18535311#18535311).  While that isn’t the exact algorithm you would need, it might give you a clue on how the DP algorithm works.

 

From: help-glpk-bounces+address@hidden [mailto:help-glpk-bounces+address@hidden On Behalf Of David Curran
Sent: Sunday, October 27, 2013 9:15 AM
To: address@hidden
Subject: [Help-glpk] cspsol webapp

 

I think it would be fun to turn cspsol into an easy to use web app.
cspsol: Simple Cutting Stock Problem Solver Using GLPK API 
https://code.google.com/p/cspsol/

 

I plan to do this at the #hack4good hackday in Dublin on Tuesday 

http://blog.geekli.st/post/64940486207/geeklist-hack4good-goes-to-the-web-summit-in-dublin

Do you have any advise on how to do this? What do you think is the best way to integrate cspsol with a web server? I presume the advise will hold for other programs based on GLPK.

One obvious way is to use the standard web programming languages to turn user input into the format cspsol wants. Then get php (or ruby or python) make a system call to run cspsol. And then to parse the results to a format that can be easily understood by the user.

Is this how you would create a web app like this?

   Thanks for the help

   David 

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