static void printMatrix() {
		String str = "\t";
		DecimalFormat df = new DecimalFormat();
		df.setMaximumFractionDigits(2);
		for (int i = 0; i < MATRIX_SIZE; i++) {
			for (int j = 0; j < MATRIX_SIZE; j++) {
				if (matrix[i][j] < 0)
					str += df.format(matrix[i][j]) + "\t";
				else
					str += " " + df.format(matrix[i][j]) + "\t";
			}
			System.out.println(str);
			str = "\t";
		}
	}