Java - quadratic formula - return an int array with double fields

Question

I need to implement the quadratic formula and my method is expecting a double array and should return a int array with the exact solution, that is, when the solution are two numbers the int array should be two fields long, when there is just one solution number the int array should be one field long and when there is no solution the int array should be empty.

I am quiet new at java and have a problem with returning the solution. Eclipse sais: "quadsol cannot be resolved to a variable." Can you help me please - where is my mistake?

This is my code:

 public static int[] quadraticFormula (double[] coefficients) {
    int i = 0;
    int j = 0;
    double discriminant;
    double solution1;
    double solution2;
    int[] quadsol = new int[j];
    discriminant = (Math.pow(coefficients[i+1],2)-(4*coefficients[i]*coefficients[i+2]));
    if(discriminant >= 0) {
        solution1 = (((Math.sqrt(discriminant)) - (coefficients[i+1]))/2*coefficients[i]);
        solution2 = ((-(Math.sqrt(discriminant)) - (coefficients[i+1]))/2*coefficients[i]);
        if(solution1 == solution2) {
            quadsol[j] = (int) solution1;
        } else {
            quadsol[j] = (int) solution1;
            quadsol[j+1] = (int) solution2;
        }
    } else {

        quadsol[j] = 0;
    }

    return quadsol;

Look up "variable scope". Then declare your variable to return outside of and before the if and else blocks, and not inside of them. — Hovercraft Full Of Eels, Dec 02 '17 at 20:01
Thank you for answering but can you be a bit more specific please? — Z.Wo, Dec 02 '17 at 20:03
Again, Google Java variable scope and study what that means. Once you learn this, it will all make sense. — Hovercraft Full Of Eels, Dec 02 '17 at 20:05
I changed the code, but can I set the number of fields to j and introduce j = 0? Does`t this mean the length of my array is zero? — Z.Wo, Dec 02 '17 at 20:17

Java - quadratic formula - return an int array with double fields

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