public Matrix extractMinor(int riga, int colonna) {
        if (this.isSquared()) {
            Matrix minore = new Matrix(this.getRows() - 1, this.getCols() - 1);
            int r = 0, c = 0;
            for (int i = 0; i < this.getRows(); ++i) {
                if (i != riga) {
                    for (int j = 0; j < this.getCols(); ++j) {
                        if (j != colonna) {
                            minore.setValue(r, c, this.getValue(i, j));
                            c++;
                        }
                    }
                    c = 0;
                    ++r;
                }
            }
            return minore;
        } else
            return null;
    }