Re: [eclipse-clp-users] 'Problem is infeasible!' in eplex goes to stdout

From: Sergii Dymchenko <>
Date: Sat, 16 Aug 2014 19:20:02 -0700
Hi Kish,

Yes, I use CLP/CBC bundled with ECLiPSe. I'll provide code that
demonstrates the issue on Monday.

I agree that suppressing all warning_output is a bad idea. I used to
do that, but now I usually just redirect warning_output and log_output
to stderr because I use ECLiPSe in batch mode and so it matters what
goes to stdout. BTW, shouldn't warning_output and log_output by
defaulr go to stderr, not stdout?


On 8/16/14, Kish Shen <> wrote:
> Hi Sergii,
> On 16/08/2014 00:54, Sergii Dymchenko wrote:> Hi,
>  >
>  > I've downloaded ECLiPSe version 6.1 #191 and now my programs that
> uses eplex
>  > often output 'Problem is infeasible!' to stdout.
>  >
> You did not say which solver you are using with eplex, but I assume you
> are using CLP/CBC. Is this correct?
>> Could you make  'Problem is infeasible!' message go to warning stream so
>> it
>> can be silenced with `:- set_stream(warning_output, null).`?
> No, ECLiPSe does not control where the solver send its messages, but the
> solver should not be sending anything directly to stdout, as its
> messages should be sent to the correct channel depending on the message
> type (error, warning, result, log). Could you please provide a simple
> example that produce this message (and could you also confirm the solver
> you are using), so that I can report the issue to the correct people
> (the developers of CLP/CBC, if this is the solver you are using).
> By the way, it is a bad idea to suppress all warning_output output, as
> this is an ECLiPSe stream, and all ECLiPSe warnings are sent there, and
> ignoring warnings sent by ECLiPSe is generally a bad idea. If you want
> to suppress warnings from the solver, you should redirect the eplex
> warning_channel instead --
> :- lp_set(warning_channel, -warning_output).
> (see the documentation for lp_set/2 for more detail).
> Cheers,
> Kish
Received on Sun Aug 17 2014 - 02:20:08 CEST

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