Urgent help regarding a problem

[Amit-1984]

Hello everyone,
i am trying to generate a custom population by overriding the newSolution() method in my problem class.
the code looks like:-
@OverRide
public Solution newSolution() {
Solution solution = new Solution(getNumberOfVariables(), getNumberOfObjectives());
for (int i = 0; i < totalClasses; i++)
{
RealVariable val = EncodingUtils.newInt(1, totalClasses);
solution.setVariable(i, val);
Variable value = solution.getVariable(i);
System.out.println(EncodingUtils.getInt(value));
}
for(int j = totalClasses; j < getNumberOfVariables(); j++)
solution.setVariable(j, EncodingUtils.newInt(1, tClass));
return solution;
}
Here, totalClasses is any number between 1 and getNumberOfVariables() value; Actually i want to initialize all values in solution before totalClasses randomly and rest of the values in solution based on already assigned values. in my above code i keep on getting output as zero always (of the statement:- System.out.println(EncodingUtils.getInt(value)))

kindly help me
and if i am doing something wrong with my implementation then kindly correct me.

Thanks in advance

[dhadka]

Since the value of the variable hasn't been set yet, it defaults to 0.

The values are typically set in the Initialization step. For example, here I create 100 random solution for the DTLZ2 problem and print their variables:

		Problem problem = new DTLZ2(2);
		RandomInitialization initialization = new RandomInitialization(problem, 100);
		
		for (Solution solution : initialization.initialize()) {
			System.out.println(Arrays.toString(EncodingUtils.getReal(solution)));
		}

If you just want to see what a randomly created variable looks like, you can call randomize():

		Variable variable = EncodingUtils.newInt(0, 5);
		variable.randomize();
		System.out.println(EncodingUtils.getInt(variable));

[Amit-1984]

@dhadka Thanks for the quick prompt.....
But i want to initialize the solutions myself and do not want just 100 random solutions. Actually i am representing the classes and interfaces in a solution and want to assign integer number to interfaces based on number assigned to classes in the solution.
like if i have 6 classes and 4 interfaces in a system then my solution is of size 10 containing integer values. the first six values are randomly initialized in newSolution() and rest 4 are based on previously assigned 6 integer values to the current solution.
And similar i am trying in my solution representation in newSolution(). Can you please guide me in this direction if i am able to make myself clear...

Thanks in advance.

[dhadka]

I see. In that case, you would just need to use one of the set methods in EncodingUtils to set the value, such as EncodingUtils.setInt(variable, 5).

Please note though that RandomInitialization, which is used by default, will overwrite any values you assign in newSolution(). You would need to use a different initialization class, such as the one below, so it uses the solutions generated by newSolution() as is.

public void NoInitialization implements Initialization {

	protected final Problem problem;

	protected final int populationSize;

	public NoInitialization(Problem problem, int populationSize) {
		super();
		this.problem = problem;
		this.populationSize = populationSize;
	}

	public Solution[] initialize() {
		Solution[] initialPopulation = new Solution[populationSize];

		for (int i = 0; i < populationSize; i++) {
			Solution solution = problem.newSolution();

			// Assume that the solutions are already initialized.  Skip calling randomize().

			initialPopulation[i] = solution;
		}

		return initialPopulation;
	}
}

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