## special sets and parameters

Problems with modeling
abb.omidi
User Posts: 27
Joined: 2 years ago

### special sets and parameters

hello
i have a flexible job shop model with below form:
i index of machines /1*2/
j index of jobs /1*3/
k index of operations /1*5/
p index of positions /1*7/
l(j,k) /1.(1*5), 2.(1*3)/ * that is, operation k for job j
f(i,p) /1.(1*5), 2.(1*3)/ * that is, position p in machine i

model have 3 dimensional parameters that is:
t(j,l,i) * that is, time of operation l in machine i
1 2
1.1 5 0
1.2 0 3
.
.
.
2.3 5 0

and ...

when run model, i have an error as below:
l in t(j,l,i) is an one dimensional set

pls. let me know, how can i define this sets & related parameters?

best regards

Renger
Posts: 550
Joined: 3 years ago

### Re: special sets and parameters

Hi

You could just define your parameter t over j,k,i.

Code: Select all

``````sets
i index of machines /1*2/
j index of jobs /1*3/
k index of operations /1*5/
p index of positions /1*7/
l(j,k) /1.(1*5), 2.(1*3)/
f(i,p) /1.(1*5), 2.(1*3)/
;

parameter t(j,k,i);

t(l,i) = uniform(0,1);

display t;

``````
If you have an equation which is defined over l and i, you could do the following

Code: Select all

``````equation
myequation(j,k,i);

myequation(l,i)..
t(l,i) =G= 0;

equations
myequation(j,k,i);

``````
Hope this helps

Renger
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