def mauna_loa(data_set='<STR_LIT>', num_train=<NUM_LIT>, refresh_data=False):
path = os.path.join(data_path, data_set)<EOL>if data_available(data_set) and not refresh_data:<EOL><INDENT>print('<STR_LIT>')<EOL><DEDENT>else:<EOL><INDENT>download_data(data_set)<EOL><DEDENT>data = np.loadtxt(os.path.join(data_path, data_set, '<STR_LIT>'))<EOL>print('<STR_LIT>', data[-<NUM_LIT:1>, <NUM_LIT:1>], '<STR_LIT>', data[-<NUM_LIT:1>, <NUM_LIT:0>])<EOL>allX = data[data[:, <NUM_LIT:3>]!=-<NUM_LIT>, <NUM_LIT:2>:<NUM_LIT:3>]<EOL>allY = data[data[:, <NUM_LIT:3>]!=-<NUM_LIT>, <NUM_LIT:3>:<NUM_LIT:4>]<EOL>X = allX[:num_train, <NUM_LIT:0>:<NUM_LIT:1>]<EOL>Xtest = allX[num_train:, <NUM_LIT:0>:<NUM_LIT:1>]<EOL>Y = allY[:num_train, <NUM_LIT:0>:<NUM_LIT:1>]<EOL>Ytest = allY[num_train:, <NUM_LIT:0>:<NUM_LIT:1>]<EOL>return data_details_return({'<STR_LIT:X>': X, '<STR_LIT:Y>': Y, '<STR_LIT>': Xtest, '<STR_LIT>': Ytest, '<STR_LIT>': [decimalyear('<STR_LIT>', '<STR_LIT>')], '<STR_LIT>': ['<STR_LIT>'], '<STR_LIT:info>': "<STR_LIT>" + str(num_train) + "<STR_LIT>"}, data_set)<EOL>
CO2 concentrations from the Mauna Loa observatory.