Hi,
I am doing my final degree work and I have been given this solution to solve with AMPL and compare with my model developed in C#.
However, I can’t manage to run it as it is in the book “Voß-Woodruff2006_Book_IntroductionToComputationalOpt” (p. 85).
I am grateful for any comments.
Thank you.
Modelo_Tabu.mod (2.4 KB)
SCPc.dat (2.7 KB)
SCPc.run (152 Bytes)
Hi @Juangl23,
One error we get when we run that script is:
Error at _cmdno 2 executing "solve" command
(file SCPc.run, line 4, offset 62):
error processing objective objective:
no value for C[2]
In SCPc.dat you have:
set PP := AJ8172 2 # Items with Lead Times
LQ8811 3
RN0098 4
NN1100 1
WN7342 12;
but the numbers seem to be for the parameter LT declared after.
By declaring the data for set PP as follows it works:
set PP := AJ8172 # Items with Lead Times
LQ8811
RN0098
NN1100
WN7342;
After setting to solver in SCPc.run (e.g., “option solver highs;”) before `solve;" we got the following output:
HiGHS 1.5.1: optimal solution; objective 9938.47165
262 simplex iterations
1 branching nodes
SCPc with 5 SKUs and 8 time buckets.
x [*,*] (tr)
: AJ8172 LQ8811 RN0098 NN1100 WN7342 :=
1jan04 100 0 9.80708e-14 -1.31292e-13 0
2jan04 0 -1.31292e-13 77.5 300 0
3jan04 0 300 0 1.97533e-13 0
4jan04 0 1.97533e-13 75 0 0
5jan04 0 0 0 0 0
6jan04 77.5 0 0 0 0
7jan04 0 0 0 0 0
8jan04 0 0 0 0 0
;
iplus [*,*] (tr)
: AJ8172 LQ8811 RN0098 NN1100 WN7342 :=
1jan04 70 90 0 0 900
2jan04 40 90 0 0 900
3jan04 130 80 0 0 600
4jan04 110 80 0 0 600
5jan04 80 80 9.9476e-14 0 600
6jan04 60 215 0 0 600
7jan04 30 215 0 0 600
8jan04 67.5 225 75 0 675
;
iminus [*,*] (tr)
: AJ8172 LQ8811 RN0098 NN1100 WN7342 :=
1jan04 0 0 0 0 0
2jan04 0 0 0 0 0
3jan04 0 0 0 0 0
4jan04 0 0 0 0 0
5jan04 0 0 0 0 0
6jan04 0 0 0 0 0
7jan04 0 0 0 0 0
8jan04 0 9.9997 0 0 75.0003
;
First of all, thank you for your response.
Regarding the resolution, I have removed what was left over in the .dat file and, sorry, but it is a given model and I don’t understand what you are explaining in “After setting to solver in SCPc.run (e.g., “option solver highs;”) before `solve;”". Please, could you develop it?
I have tried to use what I have seen in HiGHS Options — AMPL Resources but when I send the .run file to AMPL I still get the problem of the variables in the title. Why is this? Could it be that I’m not debugging properly?
Thanks in advance.
Hi @Juangl23,
With the following files:
Modelo_Tabu.mod (2.4 KB)
SCPc.dat (2.7 KB)
SCPc.run (176 Bytes)
you can then run ampl SCPc.run and it will produce the following output:
HiGHS 1.5.1: optimal solution; objective 9938.47165
262 simplex iterations
1 branching nodes
SCPc with 5 SKUs and 8 time buckets.
x [*,*] (tr)
: AJ8172 LQ8811 RN0098 NN1100 WN7342 :=
1jan04 100 0 9.80708e-14 -1.31292e-13 0
2jan04 0 -1.31292e-13 77.5 300 0
3jan04 0 300 0 1.97533e-13 0
4jan04 0 1.97533e-13 75 0 0
5jan04 0 0 0 0 0
6jan04 77.5 0 0 0 0
7jan04 0 0 0 0 0
8jan04 0 0 0 0 0
;
iplus [*,*] (tr)
: AJ8172 LQ8811 RN0098 NN1100 WN7342 :=
1jan04 70 90 0 0 900
2jan04 40 90 0 0 900
3jan04 130 80 0 0 600
4jan04 110 80 0 0 600
5jan04 80 80 9.9476e-14 0 600
6jan04 60 215 0 0 600
7jan04 30 215 0 0 600
8jan04 67.5 225 75 0 675
;
iminus [*,*] (tr)
: AJ8172 LQ8811 RN0098 NN1100 WN7342 :=
1jan04 0 0 0 0 0
2jan04 0 0 0 0 0
3jan04 0 0 0 0 0
4jan04 0 0 0 0 0
5jan04 0 0 0 0 0
6jan04 0 0 0 0 0
7jan04 0 0 0 0 0
8jan04 0 9.9997 0 0 75.0003
;
I made just two changes:
SCPc.dat:set PP := AJ8172 # Items with Lead Times
LQ8811
RN0098
NN1100
WN7342;
SCPc.run:model Modelo_Tabu.mod;
data SCPc.dat;
option solver highs; # specify the solver to use
solve;