private static void exit_with_help()
	{
		System.out.print(
		 "Usage: svm-scale [options] data_filename\n"
		+"options:\n"
		+"-l lower : x scaling lower limit (default -1)\n"
		+"-u upper : x scaling upper limit (default +1)\n"
		+"-y y_lower y_upper : y scaling limits (default: no y scaling)\n"
		+"-s save_filename : save scaling parameters to save_filename\n"
		+"-r restore_filename : restore scaling parameters from restore_filename\n"
		);
		System.exit(1);
	}