Search found 8 matches
- 6 years ago
- Forum: Solvers
- Topic: CPLEX time vs resUsd
- Replies: 5
- Views: 6599
Re: CPLEX time vs resUsd
Hey Ghassem, to what value did you set the reslim? It seems that it was too low, your limit is 1000 and the resource usage is 1017. Can you post the last part of your code with the solver options? Mona Dear Mona yes, it was too low, so I set it to 5000. it took a long long time (almost 4 hours) and...
- 6 years ago
- Forum: Solvers
- Topic: CPLEX time vs resUsd
- Replies: 5
- Views: 6599
Re: CPLEX time vs resUsd
The resUsd includes time to set up the model in Cplex and to report the solution to GAMS. For quadratic models it also included the time to extract the Q matrices from the non-linear instructions. Usually the time between resUsd and the time Cplex reports in the log is small and of not much practic...
- 6 years ago
- Forum: Modeling
- Topic: Modeling the absolute value
- Replies: 23
- Views: 22141
Re: Modeling the absolute value
Hi, the dollar command is used to manipulate the sets. For example, if the restrictions eq1, eq2, eq3 and eq4 does not apply to the last "t": eq1(n,m,t)$(ord(t) ne card(t)).. 1 - z(n,m,t) + z(n,m,t+1) + absvalue(n,m,t) =g= 1; eq2(n,m,t)$(ord(t) ne card(t)).. 1 - z(n,m,t) + 1-z(n,m,t+1) + ...
- 6 years ago
- Forum: Modeling
- Topic: Modeling the absolute value
- Replies: 23
- Views: 22141
Re: Modeling the absolute value
Just something I didn't catch
what did you mean by "$" command?
what did you mean by "$" command?
- 6 years ago
- Forum: Modeling
- Topic: Modeling the absolute value
- Replies: 23
- Views: 22141
Re: Modeling the absolute value
Thank you so much
- 6 years ago
- Forum: Modeling
- Topic: Modeling the absolute value
- Replies: 23
- Views: 22141
Re: Modeling the absolute value
Hi, Z is a binary variable and J is a scalar actually the Z variable represents a line status (being in circuit or out of it) and J represents the maximum number of lines which can get out of service I want to use the mentioned constraint to express the maximum number of switching in a system, but I...
- 6 years ago
- Forum: Modeling
- Topic: Modeling the absolute value
- Replies: 23
- Views: 22141
Re: Modeling the absolute value
Dear Friend I've Written a MIQCP code which has an absolute value in its constraints and I don't know how exactly I must write it so that the code works. here is the constraint: sum((n,m,t),abs(z(n,m,t) - z(n,m,t+1)) =l= 2*j the summation basically is based on t (time) and I want this absolute value...
Error 143
Hi everyone I've got a problem while modeling my problem and I wanted you to help me, if you can so: My model contains a quadratic term in the objective function and this makes my Linear model non-linear. I tried to write the quadratic term separately as a condition and use its result as a first-ord...