Hello
I am trying to solve the attached model using the Baron solver. However, I get the following error:
optfile=baron_option_file.txt
maxtime=-1
mipcall=0
exit value 18446744072635809797
BREAK
Note 1: I used the option mipcall=0 because of this post.
Note 2: My actual problem has a 827x827 distance matrix, but I reduced it to a 200x200 so I could post it to this forum.
Any help is much appreciated.
Felipe
new_gradual.mod (904 Bytes)
new_gradual_reduced.dat (668 KB)
Please try running this again, without mipcall=0 (which is not supposed to be needed anymore) but with outlev=1. Then copy all of the output that results, and paste it into your reply.
Hi Robert
Here is the output after several hours running the model.
ampl: solve;
BARON 21.1.13 (2021.01.13): optfile=baron_options.txt
maxtime=-1
outlev=1
BARON option outlev not recognized. Option will be ignored.
malloc of 40968 failed for recycle.c, data
Error executing “solve” command:
can’t open C:\Users\admin\AppData\Local\Temp\at5976.sol
The “malloc” program is called when more memory is needed. So the error message “malloc of 40968 failed” indicates that BARON has run out of memory: there is not enough memory on your computer for BARON to keep running. To get a better idea of what is happening, try solving a small version of your problem – say, 50x50 – and try setting a reasonable time limit, like this:
option baron_options ‘maxtime=7200 outlev=1’;
(You don’t need the optfile option is this case.) Then copy all of the BARON output that you see, and paste it into your reply.
Yes, it does work for a smaller 50x50 instance (results below).
I tried running again the original instance through the NEOS Server and I get this
Error: Your job was terminated because it exceeded the maximum allotted memory for a job.
Is there a way I could run this original instance without any hassles?
Results
Objective 19.86810477
ampl: display x;
x [*] :=
1 0 6 0 11 0 16 0 21 0 26 0 31 0 36 0 41 0 46 0
2 0 7 0 12 0 17 0 22 0 27 0 32 0 37 0 42 0 47 0
3 0 8 0 13 0 18 0 23 0 28 0 33 0 38 0 43 0 48 0
4 0 9 0 14 0 19 1 24 1 29 0 34 0 39 0 44 0 49 0
5 0 10 0 15 0 20 0 25 0 30 0 35 0 40 0 45 0 50 0
;
It appears you won’t be able to use NEOS, because your original instance requires more memory than NEOS allows. You could instead request a 30-day free trial of AMPL and solvers, and install it on your own computer (or some local computer that is available to you).
Dear Robert
Thank you for your support. I have the free trial. I tried solving it on my PC but I quit after running for more than 24h.
But it feels awkward to me that I can solve the Gradual model attached in NEOS (very fast), but the Test model I cannot, and the only difference between these models is the distance function I am using in one of the parameters, and both have exponential expressions
Gradual:
else 1 / (1+10__**__((distance[i,j] - dmin) / (rho[r] - dmin)-1/b) );
Teste:
else 1 / (1.11 + (5.118 * ((1.5distance[i,j]/24434) - (0.5((distance[i,j]/24434)^3)))));
I even tried to remove the exponential expression and I still can’t solve it.
I also tried presolving the matrix and removing this parameter and still no solution.
teste.mod (1.49 KB)
GradualCoverage.mod (1.49 KB)