> It is well known, and your links show how, to use Newton's algorithm
> (aka Newton Raphson's algorithm) to find the IRR, since it's really
> find a root of a polynomial (see the other post by Jeffery Kantor,
> which also describes the fact that depending on the cash flows, there
> could be multi
> I have a problem in mixed integer linear proramming
>
>
> The problem has variable named g , u and parameter named b
> u is binary variabel, g integer and b is parameter
>
>
> g will have value 0, if u=0
> and g>=b if u=1
>
>
> How can i write this problem?
Please see
http://lists.gnu.org
> I'm having difficulties on understanding the error message related to
> reading data file.
>
>
> "hub-location_10.dat:112: 10 items missing in data group beginning
> with _u"
>
>
> Didn't I use the correct number of parameters and set?
>
Your syntax is incorrect. Please see an example on p
> When i run my MILP i obtain the following result:
>
> Elapsed real time = 891.56 sec. (tree size = 1234.59 MB, solutions =
> 9)
> Nodefile size = 1102.85 MB (263.07 MB after compression)
> 110609 99117 7647.8916 121 18.580053997.8130 2467876
> ---
> 116645 10479214681.83
Forwarded Message
From: robin hankin
To: bug-g...@gnu.org
Subject: read.me
Date: Fri, 26 Oct 2012 22:26:28 +1300
Hello. glpk is awesome; keep it up!
There is no "read.me" file in the examples section, and I wasted quite
a long time fiddling about
getting the examples to wor
Forwarded Message
From: ze...@gmx.de
To: help-glpk@gnu.org
Subject: Read Excel data into subscripted set
Date: Fri, 26 Oct 2012 14:46:44 +0200
Hi,
I have troubles with reading a 2-dimensional table in MS Excel and
putting the data into a subscripted set. In a first step, I try t
Hi Xypron,
> in GLPK you are refer to an author "Driebeck". In
> https://www.xypron.de/webdav/Heinrich/Literature/Linear_Programming/Branching/Driebeck_1966_MSc.pdf
> I find the author to be "Norman J. Driebeek".
>
> @Article{RePEc:inm:ormnsc:v:12:y:1966:i:7:p:576-587,
> author={Norman J. Drieb
> > MIP optimzers are not fast solvers for constraint programming
> problems.
>
> That's a shame.
> What would you suggest for solving a 10x10x10 binary array subject to
> ~200 restrictions?
> It's not suitable for DLX.
>
> Also, I suspect that any insights I have into my problems will not
> imp
Forwarded Message
From: Minh Hoang
To: m...@gnu.org
Cc: help-glpk@gnu.org
Subject: Re: [Help-glpk] sensitivity analysis table in glpk [NC]
Date: Fri, 2 Nov 2012 15:19:19 -
Classification: NPL Management Ltd - Commercial
Hi Andrew,
The information in sensitivity analysis ta
> The information in sensitivity analysis table in glpk seems to be
> incorrect.
>
> For example: for the problem in sample.c file and in the manual
> section 1.3.1 (page 14).
>
[...]
> However the correct range of the row r would be 200-> +inf not (120->
> 520).
>
> Do I miss something here
> For detailed explanations of the report structure please see Section 3.4
> "Post-optimal analysis routines" in the glpk reference manual,
> pp.107-114.
>
You need reading the paragraph "Sensitivity analysis of objective
coefficients at basic variables" on pp.112-113.
> Heh. Using 'glpsol --minisat' gave the answer almost
> instantaneously [it took ~15 hours without the --minisat option].
>
Please note that --minisat allows to find only an integer feasible
solution, i.e. it solves an integer feasibility problem. To find a
better integer feasible solution y
Forwarded Message
From: Naurattan Makhija
To: help-glpk@gnu.org
Subject: .run file equivalent in GLPK?
Date: Sat, 3 Nov 2012 18:42:19 -0400
Hello,
I need to know if there is a .run file in GLPK such as in AMPL, or a
similar file that would work the same as a .run file. I have
> >If a row is non-active, changing its bounds does not affect the basic
> solution.
> This is only true for small change but not true for large change.
No, this is true for any change, assuming that a new lower bound remains
not greater than and a new upper bound remains not less than the curre
Forwarded Message
From: Steven G
To: help-glpk@gnu.org
Subject: Converting AMPL Bender's Decomposition code to GLPK
Date: Thu, 8 Nov 2012 00:45:51 -0500
Hello,
I am trying to convert the following .data .mod and .run files from APML
to GLPK. The reason for this is that I have
Forwarded Message
From: alreva
To: Help-glpk@gnu.org
Subject: [Help-glpk] adding constraints incrementally
Date: Fri, 9 Nov 2012 00:57:10 -0800 (PST)
Dear all,
I have a LP problem with a huge number of constraints which are saved into a
large file. The problem is that I can't lo
> Actually, my constraint matrix can't be fit in the memory of my
> machine. So, I assume that in cutting plane method, we don't need to
> retain all the constraints in memory, So, can you please tell me more
> about the restriction you mentioned?
You don't need to use the callback until you solv
> The main bottleneck for GLPK MIP solver is GLPK LP solver, which is
> still slow compared to CLP, for instance.
>
Success in solving mips mainly depends on cutting planes used, not on an
underlying lp solver.
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> It seems that the generated FreeMPS and MPS could not be solved as
> well in GLPK/Mathrog CLI (i.e. glpsol).
>
> However, nothing wrong with GLPK/MathProg generated FreeMPS and MPS
> MIP models. I check the other MIP models in example (e.g. bpp.mod)
>
> glpsol --math bpp.mod --wfreemps bpp_fmps
> > Looks like your instance is maximization while mps always assumes
> > minimization. You need either to change the objective sign in the
> > mathprog model or specify --max option for glpsol.
>
> I don't understand this statement. Where do you "specify -max option
> for glpsol"?
>
> e.g. glps
> >> maximize Discounted_Net_Value:
> >> sum {s in STAND, p in PERIOD} Stand_Cut_Candidates[s,p] *
> >> NPV_Calc[s,p] * FStand[s,p];
> >
> > When you pass mps to glpsol, the optimization direction
> > is minimization by default, so you need to specify the
> > --max option to tell glpsol to
> It seems that --with-zlib missing or ommitted in GLPK-4.47. It is
> present in GLPK-4.45 (I have not checked GLPK-4.4.46). I have checked
> the configure.ac of 4.47. It was not there.
>
> Any reason why it is ommitted / missing?
Now zlib is included in the glpk distribution.
>
> Here's the
Forwarded Message
From: paterijk
To: Help-glpk@gnu.org
Subject: [Help-glpk] Constraints on 2 successive elements of a set
Date: Tue, 20 Nov 2012 09:40:00 -0800 (PST)
Hi,
I'm trying to model a constraint using the GMPL modeling language.
To start, we have a set of n indices c
>
> Would this work for you?
>
>
>
> set J;
>
> var x{i in J};
>
>
>
> s.t. c{i in K : i < card(J)} x[i] >= x[i+1]
>
>
>
> -Original Message-
> From: help-glpk-bounces+marc.meketon=oliverwyman@gnu.org
> [mailto:help-glp
> >> That looks confusing? The "maximize" in the model
> >> statement should be picked up, surely?? In which case
> >> the "--max" should be unnecessary (except to override
> >> a "minimize" in the code, from the command line).
> >
> > The mps format does not allow specifying the objective sense.
Forwarded Message
From: purser
To: Help-glpk@gnu.org
Subject: [Help-glpk] Existing constraint
Date: Sun, 25 Nov 2012 23:58:14 -0800 (PST)
Hi, All!
When constraints declared, it is meaning, that each constraint must be
ensure. Is it possible to specify how at least constraints en
Forwarded Message
From: Martin Lester
Reply-to: martin.les...@cs.ox.ac.uk
To: help-glpk@gnu.org
Subject: Using a SAT solver other than MiniSAT
Date: Wed, 5 Dec 2012 23:32:18 + (GMT)
Hi.
I have a problem (an encoding of the social golfers problem) that's
significantly faste
> I have a problem (an encoding of the social golfers problem) that's
> significantly faster in gplsol with MiniSAT than in glpsol with the
> standard solver. But it's still slow on large instances and I'd like to
> try it with some other SAT solvers.
>
> I thought I'd use the --wcnf option to
> This is a question about how GLPK/GMPL handles parameters populated
> with csv table data when executing statements.
>
> I have a parameter Stand_Type (dimension 3), and a set of sets
> pres{0..1}:
> pres[0] = 1,101,102
> pres[1]= 1,2,3,4,5,6
>
> Stand_Type is indexed by { i in stands, j in pre
ype[i,j,t].
>
> I don't know what to make of it.
>
I tried to reproduce the effect (see below). As you can see,
Stand_Type[314,2,17] is *not* referenced; otherwise, this would cause a
zero divide error. Please check your model and data more carefully;
maybe that parameter member is ref
Forwarded Message
From: dante Baldeon Molleda
To: help-glpk@gnu.org
Subject: Greetings from Peru
Date: Sat, 8 Dec 2012 15:45:18 +
Hello good morning:
My monbre is Dante Baldeon belong in the National Engineering
University, specializing in pure mathematics, above all thank
r_stand[314] = 0 and pres[0] = { 1, 101, 102 }, j *cannot* be
assigned 2, and therefore Stand_Type[314,2,17] *cannot* be referenced
on computing this sum.
>
> Andrew
>
> On 08/12/2012 5:56 AM, Andrew Makhorin wrote:
> >> Thanks for your response.
> >> I entered t
Forwarded Message
From: Jean-Pierre Flori
To: help-glpk@gnu.org
Subject: Build glpk as a shared library on Cygwin, MinGW and similar
systems
Date: Mon, 10 Dec 2012 19:20:19 +0100
Dear all,
First thanks for this great library.
I'd like to be able to build glpk as a shared libra
Forwarded Message
From: Jean-Pierre Flori
To: marco atzeri
Cc: help-glpk@gnu.org
Subject: Re: [Help-glpk] [Fwd: Build glpk as a shared library on Cygwin,
MinGW and similar systems]
Date: Mon, 10 Dec 2012 20:46:25 +0100
2012/12/10 marco atzeri :
> On 12/10/2012 8:20 PM, And
Dear Prof. Fischetti,
Thank you very much for your information.
Andrew Makhorin
On Thu, 2012-12-13 at 17:34 +0100, Matteo Fischetti DEI wrote:
> Dear friends,
>
> I posted at
>
> http://www.dei.unipd.it/~fisch/proximity_search.pdf
>
> a joint work with Michele M
hard mips the solution
time grows exponentially, this approach helps not so much (until you
have 2**n processors, where n is the number of integer variables :). It
seems to me that algorithmic solutions are able to provide much greater
performance.
Andrew Mak
Forwarded Message
From: Matteo Fischetti DEI
Reply-to: m.fische...@gmail.com
To: Andrew Makhorin
Subject: randomization in MIPs
Date: Mon, 17 Dec 2012 11:28:11 +0100
Hi Andrew.
I have a paper on the role of randomization at
http://www.dei.unipd.it/~fisch/papers
> So, depending on the random seeds, your instance can be solved in 79 or
> 1816 sec.s (!!)
>
Looks like a black magic.
I encountered this when developed a mip preprocessing. At some moment it
was absolutely unclear to me to which form the original instance should
be transformed.
__
> Does anybody have tried to solve a Sudoko instance with a BigM method
> (to say "all of the digits of a line must be different").
Using integer variables (like 0 <= x[i,j] <= 9) to model sudoku
solutions together with "all different" constraints leads to a poor
formulation which is hard to solv
> As a native english speaker let me deny, on all our behalf,
> resposibility for users of internet slang. see
> http://www.internetslang.com/W_2F-meaning-definition.asp
>
IAWTC
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Best regards,
Andrew Makhorin
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Forwarded Message
From: Vladimir Dergachev
To: glpk xypron
Cc: Reginald Beardsley , help-glpk@gnu.org
Subject: Re: [Help-glpk] Optimization and Multicore GLPK
Date: Tue, 25 Dec 2012 01:03:13 -0800 (PST)
On Tue, 25 Dec 2012, glpk xypron wrote:
> Hello Reg,
>
> == Profiling ==
On Tue, 2012-12-25 at 19:00 -0200, Hugo Mezarina wrote:
> I am looking for someone willing to teach me how to model the Weighted
> Tardiness Problem (as decrived at
> http://people.brunel.ac.uk/~mastjjb/jeb/orlib/wtinfo.html) to solve it
> with glpsol and receiving the input given there.
For model
Happy New Year MMXIII
http://www.youtube.com/watch?v=3Uo0JAUWijM
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Forwarded Message
From: Matteo Fischetti DEI
Reply-to: m.fische...@gmail.com
To: Andrew Makhorin
Subject: Re: [Help-glpk] Help: How to build MIP model
Date: Fri, 04 Jan 2013 15:43:34 +0100
Hi Andrew.
to easy writing a MIP model (in Cplex) using C, I wrote the trivial
> There were posts about reenterable version of GLPK in this list:
> http://lists.gnu.org/archive/html/help-glpk/2012-12/msg00044.html
>
> I concluded from this post that reenterability can be achieved
> by changing a line glpent02.c:31
> from
> static void *tls = NULL;
> to
> static TLS void *tl
Forwarded Message
From: Ali Raza
To: help-glpk@gnu.org
Subject: GNU Program
Date: Tue, 15 Jan 2013 17:44:24 -0500
I have a quick question. I am trying to write a simple program in GNU
software. I am having difficities and it is giving me errors. I have not
used this program befo
GLPK that I use in my Java project.
> I want to prepare a more portable patch and to share it with other
> GLPK users interested in reenterable binaries.
>
Andrew Makhorin
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esn't have).
>
> If there is not, would an optional dependency on the Gnu Scientific
> Library be acceptable? That has code to compute the determinant from
> an LU decomposition that I might be able to adapt to work in GLPK to
> monitor the evolution of the solution.
>
Co
> I have been looking for around a month into glpk, mainly minimizing a
> linear problem (no integer programming).
> Some times, the problem is infeasible, and i started looking into
> Chinneck iis algorithms.
>
> As a start, I started by implementing a relaxation of a large
> infeasible proble
> PS: here is a small log of both problems
>
> GLPK Simplex Optimizer, v4.47
> 191255 rows, 68860 columns, 450946 non-zeros
> 0: obj = 0.0e+000 infeas = 5.436e+009 (28783)
> ...
> 17761: obj = -8.927238865e+008 infeas = 2.030e+007 (14520)
> PROBLEM HAS NO FEASIBLE SOLUTION
>
> Elastici
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
GLPK 4.48 Release Information
*
Release date: January 28, 2013
GLPK (GNU Linear Programming Kit) is intended for solving large-scale
linear programming (LP), mixed integer linear programming (MIP), and
other related proble
> This is a maintainer release.
Must read "This is a maintenance release."
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e to 0.
According to these rules 32:0:32 becomes 33:0:0, because some api
routines were changed/removed. Or I did something wrong?
Andrew Makhorin
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> As Jeffrey say:
> "Sometimes small changes in numerics can make a big difference in how
> the branches of an MIP problem are explored"
>
> The FPU Control Word directly impact how glpk will explore branches.
> It can be different by thread. The default value is not the same if you
> are using
GLPK 4.48 source distribution by Andrew Makhorin,
> Windows executables and libraries for 32bit and 64bit Windows as
> well as GLPK for Java 1.0.24.
>
> The download page is
> http://sourceforge.net/projects/winglpk/files/winglpk/GLPK-4.48/winglpk-4.48.zip/download
>
Thank you v
Forwarded Message
From: Softpedia Editorial Team
To: help-glpk@gnu.org
Subject: GLPK included in the Softpedia software database
Date: Tue, 5 Feb 2013 18:05:01 -0500 (EST)
Hello,
As you may already know, GLPK, one of your products, is part of Softpedia's
database of software pr
> > solution and try again. (I say 'resembles' because the TSP has a
> > special structure with permits other ways to avoid loops, these other
> > ways don't work here).
>
> > Except when I tried it didn't work, because the reason GLP_IROWGEN is
> > called with the solution to the LP relaxation, a
Forwarded Message
From: FileCluster Support
Reply-to: FileCluster Support
To: help-glpk@gnu.org
Subject: GLPK 4.48 - Filecluster.com Listing Confirmation
Date: Fri, 8 Feb 2013 13:49:50 +0200
Dear Developer,
You have received this email because we have added your application GL
Forwarded Message
From: Alexandre Saidi
To: glpk
Cc: Alexandre Saidi , Andrew Makhorin
Subject: Help demand
Date: Mon, 11 Feb 2013 10:14:48 +0100
Dears,
I've been fighting some (few) quarters with the translation of the following
constraint into GLPK.
If anybody can
On Fri, 2013-03-01 at 09:06 -0800, Sundaravalli Narayanaswami wrote:
> Hi all,
>
> I am working on a MILP model for a transportation problem, with 24
> data sets. Some of the data sets are solved to integer optimality and
> others return an integer undefined by GLPK solver.
>
> To verify and eva
elay = sum{i in 1..m, k in station} ( Weight[i] *
(actArr[i,k] ...
minimize obj: delay;
in which case the new objective will have a zero shift, and the problem
will disappear.
FYI: Your glpk version is very old. The most recent version is 4.48.
Andrew Makhorin
>
> Thanks
> SV
>
Forwarded Message
From: Guest276
To: Help-glpk@gnu.org
Subject: [Help-glpk] No mod or round function available for variables
Date: Wed, 6 Mar 2013 07:05:05 -0800 (PST)
Hi,
I am trying to solve the following problem:
I have an LP with a max objective function and some constraint
Forwarded Message
From: pmcnam
To: Help-glpk@gnu.org
Subject: Re: [Help-glpk] Any users of dwsolver (Dantzig-Wolfe)?
Date: Sat, 9 Mar 2013 07:50:18 -0800 (PST)
Hey Joey,
I'm interested in using your software though Matlab for a power systems
problem. I was wondering
a) Is it str
The following project may be interesting for you:
http://code.google.com/p/cspsol/
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On Tue, 2013-03-19 at 00:45 +0200, Figen Güngör wrote:
> Can you please look at my question at Stackoverflow?
> http://stackoverflow.com/questions/15488041/syntax-error-in-linear-programming-modelling-with-glpk?noredirect=1#comment21925482_15488041
> var po := sum{i in I} c[i]*x[i];
>
> var cos
Forwarded Message
From: Vina Shukla
To: help-glpk@gnu.org
Cc: 'Vina Shukla'
Subject: GLPK - Vehicle routing problem with time window(VRPTW)
Date: Wed, 20 Mar 2013 15:13:54 +0530
Hello!
I'm just starting with GLPK (GNU Linear Programming Kit, we would like
to use this kit f
Forwarded Message
From: Hernandez Hormazabal, Jorge
To: 'Jeffrey Kantor' , Hernandez Hormazabal, Jorge
Cc: help-glpk@gnu.org
Subject: RE: [Help-glpk] GUSEK question - MRP
Date: Mon, 25 Mar 2013 20:46:43 +
Hi Jeff, Hi all;
Thank you very much. The problem is solved. Nev
> Nevertheless, now I have another error in the line 45. I have checked
> all the brackets and everything, and I’m not sure why is the error:
> “20130325_MRP_vJEH2.mod:45: syntax error in objective statement”
>
You forgot a semicolon.
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On Tue, 2013-03-26 at 08:18 -0700, un_zero_2011 wrote:
> Hello,
>
> When I a give "glp_prob" pointer to my function that call GLPK routines like
> glp_add_rows(...) , I get the following message :
>
> "Invalid GLPK environment
> Aborted (core dumped)"
>
This error means that glpk internal memo
Forwarded Message
From: Sina Burkhardt
To: help-glpk@gnu.org
Subject: How to rewrite a nonlinear expression in a linear one
Date: Mon, 1 Apr 2013 23:31:16 +0200
Hi all,
I’m currently writing my Master thesis and I hope someone can help me to
solve the following problem(s) wi
Forwarded Message
From: Sina Burkhardt
To: 'Andrew Makhorin'
Subject: AW: [Fwd: Re: [Help-glpk] [Fwd: How to rewrite a nonlinear
expression in a linear one]]
Date: Tue, 2 Apr 2013 10:51:13 +0200
Hi Jeff,
thanks for your answer.
You're right. The idea is to us
> You don't say which Linux. For slackware try
> http://sotirov-bg.net/slackpack/pack.cgi?id=1600. For Fedora or other
> rpm systems try
> http://rpmfind.net/linux/rpm2html/search.php?query=glpk. For Debian
> try http://packages.debian.org/stable/glpk (though this is 4.43 while
> the others and th
> Unfortunately, the general case is that it will not work.
>
> The reason is that there is skew among the various Linux distros
> particularly relative to libc with the result that executables tend to
> dump core if run on a different distro. This is the reason that
> commercial software runnin
On Mon, 2013-04-08 at 18:45 +0200, Giorgio Sartor wrote:
> I have a model to which I can provide a initial feasible solution.
> How can I do that?
> The GLPK reference manual offers two different methods: one is by
> using the routine glp_read_mip and the second is by using the callback
> routine
> >>This may only mean that optimal solution to the root lp relaxation
> is
> >>integer feasible, and therefore the mip has been solved.
>
>
> Well, I thought that it wasn't true, in fact the manual says:
>
>
> The difference between optimal solution to LP relaxation and
> corresponding MIP so
-BEGIN PGP SIGNED MESSAGE-
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GLPK 4.49 Release Information
*
Release date: April 16, 2013
GLPK (GNU Linear Programming Kit) is intended for solving large-scale
linear programming (LP), mixed integer linear programming (MIP), and
other related problems
> This is great news. I have found many uses of minimum cost
> network-flow over the years, including revenue management models,
> small models for doing "first-come, first serve" and "last-come,
> first-serve" connections within the transportation industry, passenger
> rail crew rostering problem
> The University of Pisa Computer Science Department
> have also reimplemented the original RELAX-IV
> Fortran code, but into C++ instead. They offer
> their version with warning that the algorithm may
> fail to converge. The full text is:
>
> "RelaxIV is our C++ re-implementation of the
> Re
Forwarded Message
From: Dieter Kömle
To: help-glpk@gnu.org
Subject: Ipopt GMPL Interface
Date: Sun, 21 Apr 2013 20:12:46 +0200
Hello everyone!
I am new to GLPK and so far I'm very impressed by it's capabilities. My
question goes to solving non-linear problems written in GMPL u
> When I use primal simplex method to solve an unbounded LP problem.
> Checking status gives this:
> glp_get_status() returns GLP_UNBND,
> glp_get_prim_stat() returns GLP_FEAS,
> glp_get_dual_stat() returns GLP_NOFEAS.
> Then using dual simplex method to solve the same probl
> I attach a picture of a > 100% gap on integer programming on GLPK.
> Some minutes later, the gap even increased to > 200%.
>
>
> Is it normal?
>
>
> If you need, I can send you the model.
Yes, this can happen if the best integer feasible solution (incumbent
value) and the best solution to
Robbie,
There is a typo in the formula for computing mip gap on the page
http://en.wikibooks.org/wiki/GLPK/Terminal_output
The denominator should be |best_mip| + eps.
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> I got this problem below.
>
> How do I solve this?
Looks like you attempt to cross-compile, however, the assembler is not
configured properly. This error is not related to glpk neither to make.
>
> Thanks, Noli
> ~~
>
> ./configure CFLAGS="-arch x86_64 -march=native -O3" --with-gmp
>
On Mon, 2013-04-29 at 18:48 -0500, Michael Hennebry wrote:
> On Sat, 27 Apr 2013, Heinrich Schuchardt wrote:
>
> > the current definition of the MIP gap is compatible to other optimizers
> > like CPLEX.
>
> To the best of of my knowledge,
> the terminal output is designed to be read by humans.
>
> please, update the documentation to clearly point out that an error is
> thrown in glp_find_col
> and glp_find row if not preceded by a call to glp_create_index.
Okay, I will add a paragraph to clarify the issue.
>
> Wouldn't it be a good idea to let these functions implicitly call
> glp_cre
> Perhaps I'm missing something, buy why expose glp_create_index at all?
>
By default the name index is not created. If the user wants to find rows
or columns by name (i.e. to determine their ordinal numbers in the
problem object), he should enable this feature with glp_create_index.
Note that t
> Are the forall and exists iterated expressions still supported? I see
> in the documentation that both are of the form
>
>
>iterated-operator indexing-expression integrand
>
>
> but I can't seem to get either to work. Are these still supported by
> glpk v 4.45?
>
Yes, these operat
> Can you provide a link to an example of each? Any help would be
> appreciated.
>
Please see glpk/examples/color.mod (for 'exists') and
glpk/examples/egypt.mod (for 'forall').
What is wrong with these operators?
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Forwarded Message
From: Philipp
To: help-glpk@gnu.org
Subject: Invalid MEX-file
Date: Tue, 07 May 2013 15:43:18 +0200
Hallo,
i tried to use glpk with matlab but i have problem. I downloaded the
file here http://glpkmex.sourceforge.net/
and added the folder to matlab. Everytime
Forwarded Message
From: michael hegedus
To: help-glpk@gnu.org
Subject: Bound not being enforced
Date: Mon, 13 May 2013 12:15:14 -0700
I have a MIP defined that is not solving correctly because there is a
bound defined that is not being enforced.
I validated the bound is defin
row
had been added? You may try to write your mip data in a text file and
then solve it with glpsol to make sure than the mip solver finds correct
solution; if not, please report. Thanks.
Andrew Makhorin
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Forwarded Message
From: Robert Baier
To: help-glpk@gnu.org
Cc: huijuan...@uni-bayreuth.de
Subject: request for a feature (maximal iteration number or callback
function in glpk_simplex)
Date: Thu, 16 May 2013 18:30:28 +0200
Dear members of the GLPK project,
we used "glp_simplex
tware ... .
It seems to me that it would be much easier to modify the code for your
particular needs rather than to parse the terminal output via
glp_term_hook. The primal simplex code can be found in file
glpk/src/glpspx01.c and the dual simplex code in the file glpspx02.
Please note that you need to disable the lp preprocessor by setting
glp_smcp.presolve to GLP_OFF (and may be not to use automatic scaling)
that will guarantee that the internal lp is the same as your original lp
passed to the solver. Hope this helps.
Best regards,
Andrew Makhorin
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> There is one (huge and very badly scaled) problem
Just for curiosity. How big is this instance and why it is badly scaled?
> where
> "glp_simplex(..)" fails to find a feasible solution (even after two days
> of computation ...).
Maybe it would be useful to introduce artificial variables in
co
Forwarded Message
From: Sankar S1
To: xypron.g...@gmx.de, help-glpk@gnu.org
Subject: Jdk Version required for glpk-4.49
Date: Tue, 21 May 2013 15:56:22 +0530
Hi Team,
am trying to use glpk-4.49 im my Win32 machine.
Am getting below error. Please advice me is this issue bec
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
GLPK 4.50 Release Information
*
Release date: May 24, 2013
GLPK (GNU Linear Programming Kit) is intended for solving large-scale
linear programming (LP), mixed integer linear programming (MIP), and
other related problems.
Forwarded Message
From: Mayanna Oliveira
Reply-to: Mayanna Oliveira
To: help-glpk@gnu.org
Subject: Doubts about GLPK
Date: Mon, 27 May 2013 11:35:21 -0700 (PDT)
Hi,
I would like to know more about GLPK and how to use it in linear
programming. How can I use GLPK with a branch
Forwarded Message
From: Sergey Kuznetsov
To: GLPK help
Subject: Solving pure IP by calling MIP solver gives wrong status
Date: Mon, 3 Jun 2013 13:03:32 -0400
Hello,
I'm using GLPK (calling a function in c++ code) to solve a large number
of IP's, and have problems with the fol
>
> In the end I have the following output:
>
>
> Constructing initial basis...
> Size of triangular part = 2
> GLPK Simplex Optimizer, v4.45
> 2 rows, 5 columns, 10 non-zeros
> 0: obj = 0.0e+00 infeas = 1.000e+00 (0)
> * 1: obj = 1.7e-01 infeas = 0.000e+00 (0)
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