-------- Forwarded Message --------

Date: Thu, 6 Aug 2020 17:12:26 -0300
Subject: Exportation/importation problem that seems to be related to
decimal numbers
To: [email protected]
From: Sylvain Fournier <[email protected]>
> Hi,
> 
> I'd like to be able to export a model into a (text) file in order to
> be able to run it again later. I noticed there are three couples of
> procedures for this:
> glp_write_lp / glp_read_lpglp_write_prob / glp_read_probglp_write_mps
> / glp_read_mpsI tried with each of them, and failed to import the
> model for specific reasons:
> glp_*_lp: the exported file shows decimal numbers using a comma
> instead of a dot (it must be because it is the way to write decimals
> in Brazil). As a result, when trying to import back, I get the
> following message: "(line) 4: constraints section missing". Note that
> if I manually replace the comma by a dot, I get another error: "4:
> numeric constant '93.2807074368' out of range".
> glp_*_prob: when trying to import the file back, the program stops at
> the first line describing the objective coefficients (starting with
> 'a') with the following message: "error: objective coefficient
> missing or invalid". If I replace the ',' by a dot, I get the same
> message.
> glp_*_mps: here it is even more strange. It seems that the exported
> file describes a cost function very different from the original model
> one (coincidentally - or not -, the only decimal numbers in this
> model are the variables cost coefficients). In fact, it looks like it
> mistook one of the constraints with the cost coefficients. I could
> send the original (lp) file and the generated (mps) file for a better
> understanding of the issue, if needed. Besides, the generated file
> doesn't export the rows and columns names, but instead uses names
> like C0000143 or R0000143, which makes the model far more difficult
> to understand.
> 
> Note that I am running GLPK through the Java wrapper libglpk-java-
> 1.12.0.
> Am I doing something wrong? Is there some workaround to this issue?
>  
> Sylvain Fournier
> Operations Research Manager
> 48 3239-2428
> 
>       
> WPLEX Software Ltda.
> 
> Rod SC 401 no. 8600 Corporate Park bloco 5 sala 101
> 
> 88050-000 Santo Antônio de Lisboa, Florianópolis SC +55 48 3239-2400
> 
> wplex.com.br
> 
> 
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> 

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