Java: Call/Return Error

I am having some trouble returning matrix data from one method to the main class, I am using:

matrix =  setFalse(falseMatrix);

to call:

public static boolean[][] setFalse (boolean[][] matrix[][]) {

        // Changes each value of the matrix to a false boolean value

        boolean[][] falseMatrix = null;

        for (int r = 0; r < ma开发者_如何转开发trix.length; r++ ) {
            for (int c = 0; c < matrix[0].length; c++ ) {
                falseMatrix[r][c] = false;

            }
        }
        return falseMatrix;

    } 

I am getting the error that falseMatrix cannot be resolved to a variable, but when I make it a parameter I get a fatal error.

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Your code is currently very confused. I suspect you want:

public static boolean[][] setFalse(boolean[][] matrix) {
    // Changes each value of the matrix to a false boolean value

    for (int r = 0; r < matrix.length; r++ ) {
        for (int c = 0; c < matrix[r].length; c++ ) {
            matrix[r][c] = false;
        }
    }
    return matrix;
}

How you then call the method is a different matter. You need to already have a variable (or some other expression) of type boolean[][]. Unfortunately you haven't shown us any of the context of the calling code.

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change

(boolean[][] matrix[][]) {

to

(boolean[][] matrix) {

and

boolean[][] falseMatrix = null;

to

boolean[][] falseMatrix = new boolean[matrix.length][];

and insert between the two for

falseMatrix[r] = new boolean[matrix[r].length];

and finally change in 2nd for

matrix[0].length;

to

matrix[r].length;

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Change:

public static boolean[][] setFalse (boolean[][] matrix[][]) {

To:

public static boolean[][] setFalse (boolean[][] matrix) {

Also, initialize your array:

    //HERE
    boolean[][] falseMatrix = new boolean[matrix.length];

    for (int r = 0; r < falseMatrix.length; r++ ) {
    //AND HERE
        falseMatrix[r] = new boolean[matrix[0].length];
        for (int c = 0; c < falseMatrix[r].length; c++ ) {
            falseMatrix[r][c] = false;
        }
    }

    return falseMatrix;
} 

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 for (int r = 0; r < matrix.length; r++ ) {
            for (int c = 0; c < matrix[0].length; c++ ) {

you should probably change matrix[0] to matrix[r]. Not sure if it solves your problem, but Im pretty sure thats what you want.

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boolean[][] falseMatrix = null;

falseMatrix is a null reference. You have to initialize it to with rows, columns before trying to keep values at it's indices.

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On the first line (the calling line) you are using two different variables, falseMatrix and matrix, since it's giving error on falseMatrix then I suppose it's the wrong one.

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You need:

boolean[][] falseMatrix = new boolean[matrix.length][matrix[0].length];