ValueError:无法使用长度与值不同的多索引选择索引器进行设置

Question

我在处理数据集时遇到此错误

ValueError: cannot set using a multi-index selection indexer with a different length than the value

我以前使用过这段代码，但对于相同类型的数据，它总是运行良好，但现在它不起作用

for dataset in data_df:
dataset.at[dataset['Ozone'] <= 54, 'Ozone'] = 0,
dataset.at[(dataset['Ozone'] > 54) & (dataset['Ozone'] <= 70), 'Ozone'] = 1,
dataset.at[(dataset['Ozone'] > 70) & (dataset['Ozone'] <= 85), 'Ozone'] = 2,
dataset.at[(dataset['Ozone'] > 85) & (dataset['Ozone'] <= 105), 'Ozone'] = 3,
dataset.at[(dataset['Ozone'] > 105) & (dataset['Ozone'] <= 200), 'Ozone'] = 4

Answer 1

只需像这样删除每行后面的逗号，然后再次运行

for dataset in data_df:
dataset.at[dataset['Ozone'] <= 54, 'Ozone'] = 0
dataset.at[(dataset['Ozone'] > 54) & (dataset['Ozone'] <= 70), 'Ozone'] = 1
dataset.at[(dataset['Ozone'] > 70) & (dataset['Ozone'] <= 85), 'Ozone'] = 2
dataset.at[(dataset['Ozone'] > 85) & (dataset['Ozone'] <= 105), 'Ozone'] = 3
dataset.at[(dataset['Ozone'] > 105) & (dataset['Ozone'] <= 200), 'Ozone'] = 4