Java Fitness Function

I am having trouble getting the fitness function to work on my code. All that I end up with is the binary String "10101".

I would greatly appreciate it if somebody could assist me as I have spent an extremely long time on this and not gotten anywhere.

Here is the code:

public class Fitness{

public static void main(String args[]){

    ScalesSolution s = new ScalesSolution("10101");
    s.println();

    ArrayList<Double> weights = new ArrayList<Double>();

        weights.add(1.0);
        weights.add(2.0);
        weights.add(3.0);
        weights.add(4.0);
        weights.add(5.0);
        weights.add(6.0);
        weights.add(7.0);
        weights.add(17.0);
        weights.add(117开发者_如何学运维.0);
        weights.add(3427.0);
        weights.add(5437.0);
        weights.add(567.0);
        weights.add(7567.0);

    ScalesSolution.scalesFitness(weights);
    System.out.println();

    }
}

The fitness function is as follows:

public class ScalesSolution{

    private static String scasol;
//Creates a new scales solution based on a string parameter
//The string parameter is checked to see if it contains all zeros and ones
//Otherwise the random binary string generator is used (n = length of parameter)
public ScalesSolution(String s)
{
    boolean ok = true;
    int n = s.length();
    for(int i=0;i<n;++i)
    {
        char si = s.charAt(i);
        if (si != '0' && si != '1') ok = false;
    }
    if (ok)
    {
        scasol = s;
    }
    else
    {
        scasol = RandomBinaryString(n);
    }
}
private static String RandomBinaryString(int n)
{
    String s = new String();

    for(int i = 0; i < s.length(); i++){
        CS2004.UI(0,1);
            if(i == 0){
                System.out.println(s + "0");
            }
            else if(i == 1){
                System.out.println(s + "1");
            }
    }

    return(s);
}
public ScalesSolution(int n) 
{
    scasol = RandomBinaryString(n); 
}
//This is the fitness function for the Scales problem
//This function returns -1 if the number of weights is less than
//the size of the current solution



public static double scalesFitness(ArrayList<Double> weights)
{   
    if (scasol.length() > weights.size()) return(-1);
    double lhs = 0.0,rhs = 0.0;

    double L = 0.0;
    double R = 0.0;

    for(int i = 0; i < scasol.length(); i++){
        if(i == 0){
            L = L += i;
        }
        if(i == 1){
            R = R += i;
        }
    }//end for

    int n = scasol.length();

    return(L-R);

    //return(Math.abs(lhs-rhs));

}
//Display the string without a new line
public void print()
{
    System.out.print(scasol);
}
//Display the string with a new line
public void println()
{
    print();
    System.out.println();
}
}

When I run the program, the output is as follows:

10101

There is nothing more, no matter what I enter for values of the ArrayList...

I have been racking my brain for hours and am still nonethewiser - any help would be greatly appreciated!

Thank you so much.

Mick.

EDIT: The code has now been updated and the complete class is listed - apologies for any confusion.

---

I don't know exactly how this code is supposed to work, but one piece that looks suspicious to me is the following:

for(int i = 0; i < scasol.length(); i++){
        if(i == 0){
        L = L += i;
    }
    if(i == 1){
        R = R += i;
    }
    }//end for

You never examine any of the values in scasol; should you be? i.e. something like

for(int i = 0; i < scasol.length(); i++){
            if(scasol.getCharAt(i) == '0'){
            L = L += 0;
        }
        else if(scasol.getCharAt(i) == '1'){
            R = R += 1;
        }
        }//end for

The way you have written now, you're comparing the iteration index rather than the value at that index.

The other problem as others mentioned is you don't print the result:

ScalesSolution.scalesFitness(weights);
System.out.println();

should be:

 double fitness = ScalesSolution.scalesFitness(weights);
System.out.println(fitness);

---

I think your problem is at the empty System.out.println();. I would try the next:

double returnedValue= ScalesSolution.scalesFitness(weights);
System.out.println(returnedValue);

You need to store your returned value at a variable, and then pass this variable to the methods where you want to use the value (in this case, printing it to the console statndard output via println method).

---

is that code complete??

at the beginning you call

ScalesSolution s = new ScalesSolution("10101");
s.println();

and I can't find the constructor or the method s.prinln();

but it seems like you print your Input String - and not any binary thing

---

You are nowhere using or even printing the result of your ScalesSolution.scalesFitness(weights); call, so no wonder it would not print anything.