[Scip] Define parameters in ZIMPL
Thorsten Koch
koch at zib.de
Sun May 16 00:21:39 MEST 2010
Dear Julio,
it is not clera to what you want to achieve.
Am 15.05.2010 16:38, schrieb Julio Rojas:
> Dear Thorsten, I have followed your advice and changed my code to:
>
> param s[<i,j> in e2] := ord(p,j in {1..card(p)},1) default 0;
>
s[3,4] has to resolve to a single number.
What do you want from the j in { 1 .. 3 } ?
j is already fixed from the s[<i,j> in e2] so it is some number.
But then 2 in { 1 .. 3} does not make much sense.
Best regards,
Thorsten
> Now, the error changed to:
>
> Reading problem.zpl
> *** Error 800: File problem.zpl Line 7 : syntax error, unexpected IN,
> expecting
> ',' or '+' or '-'
> *** aram s[<i,j> in e2] := ord(p,k in {1..card(p)},1) default 0;
> *** ^^^
>
> Any other idea? Am I forcing things and should stick to define the
> parameters by hand from my program (two loops)?
>
> Best regards.
> -------------------------------------------------
> Julio Rojas
> jcredberry at gmail.com
>
>
> On Sat, May 15, 2010 at 3:35 PM, Thorsten Koch <koch at zib.de> wrote:
>
>> Dear Julio,
>>
>> you can not access a member of a set (p) by use of [].
>> if you do p[] you try to access an array of sets (which is not defined
>> in this case)
>> You can access a member of a set using the ord() function.
>>
>> Furthermore, a parameter is always only a single value.
>>
>> Here
>>> param s[<i,j> in e2] := p[i in {1..card(p)}] default 0;
>> ^
>> This i
>> is equal to the i from <i,j>.
>> The expression on the right hand side is not depending on j.
>> In any case it should read p[<i> in ... but this won't work either.
>>
>> But I believe ord() will do what you need.
>>
>> Best regards,
>> Thorsten
>>
>>
>> param s[<i,j> in e2] := ord(p([i in {1..card(p)}] default 0;
>>
>> Am 14.05.2010 20:18, schrieb Julio Rojas:
>>> Dear Armin and Ambros, not really. I'll like to put the k-th element of
>> the
>>> set p in the <i,j>-th position of the parameter matrix s. I have already
>>> defined e2 (but didn't put it in my previous email) and I wouldn't like
>> to
>>> create the matrix of parameters one by one as it is stated in the manual.
>>> The matrix s is a triangular matrix with zeros in the diagonal (in
>> reality
>>> is a distance matrix). I would like to fill each element of the matrix
>> from
>>> a set. This way I will not have to make a double loop in my code to
>> define
>>> each element <i,j> with i<j. This is the code I already have:
>>>
>>> set nodes := {"1","2","3"};
>>> set e2 := {<i,j> in nodes*nodes with i<j};
>>> set p := {.1,.2,.3};
>>> var y[<i,j> in e2] binary;
>>> var x[<i> in nodes] binary;
>>> param s[<i,j> in e2] := p[i in {1..card(p)}] default 0;
>>> maximize sim: sum<i,j> in e2: s[i,j]*y[i,j];
>>>
>>> Best regards.
>>> -------------------------------------------------
>>> Julio Rojas
>>> jcredberry at gmail.com
>>>
>>>
>>> 2010/5/14 Armin Fügenschuh <fuegenschuh at zib.de>
>>>
>>>> Dear Julio,
>>>>
>>>> is this the thing you're trying to do?
>>>>
>>>> set p := {.1,.2,.3};
>>>> set e2 := p*p;
>>>> param s[<i,j> in e2] := j;
>>>> var y[e2] real;
>>>> maximize sim: sum<i,j> in e2: s[i,j]*y[i,j];
>>>>
>>>>
>>>> Regards,
>>>> Armin
>>>>
>>>>
>>>> 2010/5/14 Julio Rojas <jcredberry at gmail.com>
>>>>
>>>>> Dear all, I would like to define the matrix of parameters from a set. I
>>>>> have tried with the following:
>>>>>
>>>>> set p := {.1,.2,.3};
>>>>> param s[<i,j> in e2] := p[i in {1..card(p)}] default 0;
>>>>> maximize sim: sum<i,j> in e2: s[i,j]*y[i,j];
>>>>>
>>>>> The following message appears:
>>>>>
>>>>> *** Error 800: File problem.zpl Line 7 : syntax error, unexpected
>> SETSYM
>>>>> *** param s[<i,j> in e2] := p[<i> in {1..card(p)}] default 0;
>>>>> *** ^^^
>>>>>
>>>>> Is there a way to do this? Thanks in advance.
>>>>> -------------------------------------------------
>>>>> Julio Rojas
>>>>> jcredberry at gmail.com
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> Scip mailing list
>>>>> Scip at zib.de
>>>>> http://listserv.zib.de/mailman/listinfo/scip
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>>
>>>> Dr. Armin Fügenschuh
>>>>
>>>> Konrad-Zuse-Zentrum für
>>>> Informationstechnik Berlin (ZIB)
>>>>
>>>> Division Scientific Computing
>>>> Department Optimization
>>>>
>>>> Takustrasse 7
>>>> 14195 Berlin
>>>>
>>>> Tel. : +49 (0)30 84185-205
>>>> Fax: +49 (0)30 84185-269
>>>> email: fuegenschuh at zib.de
>>>>
>>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> Scip mailing list
>>> Scip at zib.de
>>> http://listserv.zib.de/mailman/listinfo/scip
>>
>> --
>> The important thing is not to stop questioning.
>> Curiosity has its own reason for existing. -- Albert Einstein
>> ______________________________________________________________________
>> Dr. Thorsten Koch / Konrad-Zuse-Zentrum für Informationstechnik Berlin
>> www.zib.de/koch / Takustraße 7, 14195 Berlin-Dahlem, Germany
>> koch at zib.de / Phone +49-30-84185-213, Fax -269
>> _______________/ DFG Research Center "Matheon" http://www.matheon.de
>>
>> Kooperativer Bibliotheksverbund Berlin Brandenburg http://www.kobv.de
>> ______________________________________________________________________
>>
>
--
The important thing is not to stop questioning.
Curiosity has its own reason for existing. -- Albert Einstein
______________________________________________________________________
Dr. Thorsten Koch / Konrad-Zuse-Zentrum für Informationstechnik Berlin
www.zib.de/koch / Takustraße 7, 14195 Berlin-Dahlem, Germany
koch at zib.de / Phone +49-30-84185-213, Fax -269
_______________/ DFG Research Center "Matheon" http://www.matheon.de
Kooperativer Bibliotheksverbund Berlin Brandenburg http://www.kobv.de
______________________________________________________________________
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