[Cmpl] help

[Mike Steglich]

Hi Priyanki,

Can you give me more information about the information you need. 

CMPL and pyCmpl provide information for each variable and constraint about the activity, the bounds and if the model isn't  an integer program the marginals (shadow price  or reduced cost).

Cheers,

Mike


Am 24.09.2013 um 17:15 schrieb Priyanki Sharma:

> Hello Mike,
> 
> Is there any way of generating any default reports like sensitivity report etc in Coliop . I mean the kind of default report we can produce in excel risk solver etc. 
> Thanks 
> 
> cheers
> Priyanki
> 
> 
> From: Mike Steglich <mike.steglich at berlin.de>
> To: Priyanki Sharma <priyankiarch at yahoo.com> 
> Sent: Thursday, 19 September 2013 6:39 PM
> Subject: Re: [Cmpl] help
> 
> Hi Priyanki,
> 
> Thank you for the kind words.
> 
> One note to the term weak SOS. It wasn't a description of the quality of your constraints. 
> 
> A weak SOS1 is like:           x[1] + x[2]  + x[3] <= 1. That means (assuming that the x variables are binaries for projects) that maximally one project can be realized.
> A strong SOS1 looks like:    x[1] + x[2]  + x[3] = 1 Exact one project is to be realized. 
> 
> Cheers,
> 
> Mike
> 
> Am 19.09.2013 um 01:14 schrieb Priyanki Sharma:
> 
>> Hello Mike,
>> 
>> First of all, thank you so much. I have known so much more about the usage of cmpl through this code.  The usage of loops in the variable section is surely new to me. Yes I agree that the con2 was weak. Initially, Con1 has worked with your previous suggestion but I think this is a better way of dealing with it. 
>> Thanks a lot Mike for your help. Its been a learning experience for me. I will keep all your suggestions in mind when I do the next code. Really appreciate your help. 
>> 
>> Have a good day,
>> 
>> Cheers :))
>> Priyanki
>> 
>>  
>> 
>> 
>> From: Mike Steglich <mike.steglich at berlin.de>
>> To: Priyanki Sharma <priyankiarch at yahoo.com> 
>> Sent: Wednesday, 18 September 2013 8:20 PM
>> Subject: Re: [Cmpl] help
>> 
>> Hello Priyanki,
>> 
>> please find attached a CMPL file that should solve your problem. The problem was that your with the first proposal all language and plane constraints have to be fulfilled for an valid crew assignment. This forces your model to be infeasible. But if only one of the constraints (for both groups … language and plane) is satisfied a crew assignment is valid. Therefore I determine the valid crew combination due to the language and plane skills in the parameter section and use the corresponding parameter arrays valid_lan_combination[i,j,k] and valid_lan_combination[i,j,m] within the changed constraint con1. Additionally I calculate the max scores for each valid crew and use it in the objective function.
>> 
>> The second problem was your formulations of the weak SOS 1. Please take a look of the reformulated constraint con2.
>> 
>> 
>> 
>> Hope that helps. 
>> 
>> Cheers,
>> 
>> Mike
>> 
>> 
>> 
>> 
>> 
>> Am 18.09.2013 um 00:44 schrieb Priyanki Sharma:
>> 
>>> Mike,
>>> 
>>> Thanks a lot for your help on the first part of the question. Can you please tell me how to calculate the max value for the second part of the question. How to generate the loop that calculates the max as score.  I would really appreciate that. 
>>> Thanks again
>>> 
>>> cheers
>>> Priyanki
>>> 
>>> 
>>> From: Mike Steglich <mike.steglich at berlin.de>
>>> To: Priyanki Sharma <priyankiarch at yahoo.com> 
>>> Cc: "cmpl at list.coin-or.org" <cmpl at list.coin-or.org> 
>>> Sent: Wednesday, 18 September 2013 4:07 AM
>>> Subject: Re: [Cmpl] help
>>> 
>>> Hello Pryanki,
>>> 
>>> I did not check the entire model. But your first group of constraints (e.g.  x[i,j] * R_lan[i,k] >= 10)  forces your model to be infeasible:
>>> 
>>> For the two cases for a x[i,j] we have the following results
>>> 1) x[i,j] = 0   ->   x[i,j] * R_lan[i,k] >= 10  -> False, because 0>=10 is wrong
>>> 2) x[i,j] = 1   ->   x[i,j] * R_lan[i,k] >= 10  -> True or False, because 1*  R_lan[i,k] >=10 is true if R_lan[i,k] >= 10 or false if R_lan[i,k] < 10
>>> 
>>> A better formulation could be:
>>> R_lan[i,k] >= 10 * x[i,j] 
>>> 
>>> because:
>>> 1) x[i,j] = 0   ->  R_lan[i,k] >= 10 * x[i,j]  -> True, because R_lan[i,k] >=0 is true
>>> 2) x[i,j] = 1   ->  R_lan[i,k] >= 10 * x[i,j]  -> True, because R_lan[i,k] >=10 is true if R_lan[i,k] >= 10 or  if R_lan[i,k] < 10 then x[i,j] is forced to become 0
>>> 
>>> 
>>> Cheers,
>>> 
>>> Mike
>>> 
>>> 
>>> Am 17.09.2013 um 18:40 schrieb Priyanki Sharma:
>>> 
>>>> Hello ,
>>>> 
>>>> I have been trying to solve this cmpl code. It gives infeasible all the time. I don't understand why this is happening. I have attached the question in a word document and the cmpl code . I am trying to solve the first part of the question but there is something wrong with the first constraint called " con1". I just can't figure out what is going wrong. Its quite urgent. Could someone please help. I would really appreciate any help asap.
>>>> 
>>>> Thanks
>>>> 
>>>> Regards
>>>> Priyanki
>>>> <During the Second World War the Royal Air Force.docx><final test4.cmpl>_______________________________________________
>>>> Cmpl mailing list
>>>> Cmpl at list.coin-or.org
>>>> http://list.coin-or.org/mailman/listinfo/cmpl
>>> 
>>> 
>>> 
>>> <During the Second World War the Royal Air Force.docx><final test5.cmpl>
>> 
>> 
>> 
> 
> 
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/cmpl/attachments/20130924/720a857b/attachment.html>