need help to output solution pool as a parameter

GAMS
1

Hello,

my program below counts from 0 to 7 in binary (x.l varies from 000 to 111) in gams,
Now I want to collect the solutions of all the iteration to output a table parameter, which is

t1 t2 t3
g0 0 0 0
g1 0 0 1
g2 0 1 0
g3 0 1 1
g4 1 0 0
g5 1 0 1
g6 1 1 0
g7 1 1 1

how can I do in gams?

sets t /t1*t3/;
scalars c /-1/;
parameters b(t);
binary variables x(t);
variables z;
equations
obj
eq;
obj… z =e= sum(t,b(t)x(t));
eq… z =e= c;
model prob /all/;
b(‘t1’)=1;
loop(t,
b(t+1)=2b(t);
);
repeat (
c=c+1;
solve prob using mip minimizing z;
until c=7
);
display x.l

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2

Hi Zhu



You could code this as follows:



parameter results(g,*);

repeat (

c=c+1;

solve prob using mip minimizing z;

results(g,t)$(ord(g) = c+1) = x.l(t) ;

results(g,“c”)$(ord(g) = c+1) = c + EPS;



until c=7

);

display results;



Note, that I added EPS, because in the first iteration, all results are zero, so it wouldn’t display in the table. Adding EPS (a very small value in Gams) will give you all entries.

I also added the value of c in the results, so I can check if it really is using the correct value of c in the loop. For this I added a * in the parameter definition of results, so I can put whatever I want here (t and “c”).

Hope this helps

Renger


\

Renger van Nieuwkoop

Department of Management, Technology and Economics

Centre for Energy Policy and Economics

Swiss Federal Institute of Technology Zurich

Zürichbergstrasse 18, 8032 Zurich, Switzerland



Mobile: +41 79 818 53 73

E-Mail: rengerv@ethz.ch

Blog: http://blog.modelworks.ch







From: gamsworld@googlegroups.com [mailto:gamsworld@googlegroups.com] On Behalf Of Songming Zhu
Sent: Tuesday, November 4, 2014 12:18 AM
To: gamsworld@googlegroups.com
Subject: Re: need help to output solution pool as a parameter



Hello,



my program below counts from 0 to 7 in binary (x.l varies from 000 to 111) in gams,

Now I want to collect the solutions of all the iteration to output a table parameter, which is



t1 t2 t3

g0 0 0 0

g1 0 0 1

g2 0 1 0

g3 0 1 1

g4 1 0 0

g5 1 0 1

g6 1 1 0

g7 1 1 1



how can I do in gams?



sets t /t1*t3/;
scalars c /-1/;
parameters b(t);
binary variables x(t);
variables z;

equations
obj
eq;
obj… z =e= sum(t,b(t)*x(t));
eq… z =e= c;
model prob /all/;

b(‘t1’)=1;
loop(t,
b(t+1)=2*b(t);
);

repeat (
c=c+1;
solve prob using mip minimizing z;
until c=7
);
display x.l

–
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To post to this group, send email to gamsworld@googlegroups.com.
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For more options, visit https://groups.google.com/d/optout.

–
To unsubscribe from this group and stop receiving emails from it, send an email to gamsworld+unsubscribe@googlegroups.com.
To post to this group, send email to gamsworld@googlegroups.com.
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For more options, visit https://groups.google.com/d/optout.