Originally posted by: CynthiaLi

I built an OPL project with two model files and one data file. The main model file contains the model for the master problem, and a main{} scripting block to iteratively solve the master problem and the subproblem which is defined in another model file. The data file is for the master model.
However, when I run the project, there is an error called "File 'Null' Not Found", and it points at "main". What is the meaning of the error? Where may I go wrong?
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Originally posted by: FredericDelhoume

Can you explain (or show) your project structure along with the model ?
It is likely that you cannot access one of the referenced files, certainly because
it is not in searched path.
A screen dump of the project structure and exact error will help understanding what happens.

Thanks,
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Originally posted by: CynthiaLi

Thanks for your reply. I attached the snapshot.
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Originally posted by: FredericDelhoume

Thanks,

May I ask for contents of the Scripting log ?
You may also add regular traces or use the integrated script debugger to get the location of the
problem, as OPL currently seem to be unable to determine it (this why it defaults to main location).

You can set a breakpoint using double click in left margin in editor at first scripting line, then use stepping to see where exactly it triggers the error.
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Originally posted by: CynthiaLi

The Scripting log shows:
Solve First Stage Problem.
theta: 0
x: 0 0
Optimal Value:0
// Script execution failed with status -2
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Originally posted by: FredericDelhoume

This log says that code we wee in your screendump does not trigger the error, we can see line 79 beeing executed once.
So please show the rest of your main code, as error is certainly in hidden part.
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Originally posted by: CynthiaLi

I guess there may be something wrong with the definition of one of my var within main location.
Here is what I am trying to do:
I defined a tuple in my first optimization model. Then in the main block, I want to add data into this tuple. The tuple OCut is defined as follows:
tuple OCut {
key int id;
float SmallE;
float BigEVarX;
}

The difficult part is the last component.
I want to define a numerical array Big[n] to save the calculated results, then add the data in the tuple data :
FirstData.OCuts.add(FirstData.OCuts.size,Small,Big);

How shall I define the numerical array Big[n] and set every component to be zero first?
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Originally posted by: FredericDelhoume

I am no expert in modeling so I will let other ask.
Are you sure your problem (null file) is related to this ?
Looks like something different to me.
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Originally posted by: CynthiaLi

This is another snapshot.
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Originally posted by: SystemAdmin

Hi,

I would declare the array Big by script (+var Big = new Array();+)
and initialize it when you have data for Big with something like:
Big[i] = calculatedResult;

main {
http://...
var Big = new Array();
http://...
for (var i=0;i<n;i++) {
your model instantiation and solve block
Big[i] = calculatedResult;
FirstData.OCuts.add(FirstData.OCuts.size,Small,Big[i]);
...
}
}

Hope this helps.
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Originally posted by: CynthiaLi

Thanks for your help. I guess it works since the message of error changed.
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Originally posted by: FredericDelhoume

Your initial error was probably happening at line 99 form error2.png screen dump
Big[p] = new IloOplDataSource(Bigp]);

this is because IloOplDataSource only accepts files as constructor argument.
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