Originally posted by: SystemAdmin

Hi,

I have a following problem in my model. Kindly refer my attachment which will give a better understanding of my below description. I have a parameter Paths which is a binary type. It's notation is,

Paths{i,s,d,l}

i - index of path
s - source node
d - destination node
l - link occurs in that path

In my data model, I have represented as,

Paths{1,2,9,*} 2 1 3 1 4 1 5 1 6 1

Here in the above example, for index i(i.e., value 1), source node 2 and destination node 9, the links such as 2,3,4,5,6 forms a path, and in between the links i placed boolean value 1 to represent a boolean parameter, it will checks if the link is available or not and then returns the boolean value. Here, those links mentioned will return 1 since it contains the links in that path. The basic idea is if this parameter contains the links then this parameter Paths should return boolean value in my constraints section which I have used in my model.

I would like to represent this approach in data model and OPL model. I am struck and dont have any clue. Kindly help me as soon as possible.

I kindly request someone to help me as soon as possible. I already posted in other thread long time back but I dint get any reply so far. But I have explained a little bit deep to understand my problem anyways.

Thanks!!!
#DecisionOptimization
#OPLusingCPLEXOptimizer

Hi,

could the following help you?

.mod

tuple link
{
  int node;
  int paramnode;
}  
tuple path
{
 int index;
 int source;
 int destination;
 {int} links; 
 {int} linksWithParamTrue;
}  
 
{path} paths=...;

.dat

paths={<1,2,9,{2,3,4,5,6},{2,3,4,5,6}>};

Regards
#DecisionOptimization
#OPLusingCPLEXOptimizer

Originally posted by: SystemAdmin

Hi,

Thanks for the reply. Here I have few more questions based on my model.
Why tuple has been used for links as well from the example you gave?
How to declare a variable as Binary?
I have a condition like this shown below, Will it work?

float LinkPowerl in Links = (Capacityl in Links<1000) ? 60 : (Capacityl in Links<2000) ? 100 : (Capacityl in Links<4000) ? 140 : (Capacityl in Links<10000) ? 174 : 0 ;
If you check my .dat file which I have attached in this thread in the previous posts, there is a parameter Capacity and Pairs are used. How can I use in OPL .dat file to represent the same?
Kindly help me to model....

Thanks
#DecisionOptimization
#OPLusingCPLEXOptimizer

Hi

tuple link is useless

tuple path 
{ 

int index; 

int source; 

int destination; 
{

int
} links; 
{

int
} linksWithParamTrue; 
}   
{path
} paths=...;

works fine.

To declare a binary decision variable:

dvar 

boolean bVar;

For your LinkPower question, you can write:

.mod

{

int
} links=...;   

int Capacity[links]=...;   

float LinkPower[l in links] = (Capacity[l] <1000) ? 60 : (Capacity[l] <2000) ? 100 : (Capacity[l] <4000) ? 140 : (Capacity[l] <10000) ? 174 : 0;

.dat

links=
{1
};   Capacity=[1000];

#DecisionOptimization
#OPLusingCPLEXOptimizer

Originally posted by: SystemAdmin

Hi,

Thanks for the help. Also I have asked about parameter *Pairs*?. The idea of this parameter is to map the bi-directional links in my model. If you check my .dat file provided in the previous posts, I have actually mapped link{1} to link{2} and so on for remaining links. How can I declare and initialize in .mod and .dat file in OPL?
I have a parameter Demand in my data model file. It is represented as D{s,t}. It has a value for each s and t which is formed as array. How can I formulate this .mod and .dat file in OPL?
Thanks
#DecisionOptimization
#OPLusingCPLEXOptimizer

Hi,

there is a nice example of 2 dimensions array in the documentation at

IDE and OPL > Optimization Programming Language (OPL) > Language Reference Manual > OPL, the modeling language > Data sources > Data initialization

/* .mod file */
int a[1..2][1..3] = ...;
/* .dat file */
a = [
[10, 20, 30],
[40, 50, 60]
];

regards
#DecisionOptimization
#OPLusingCPLEXOptimizer