python - 类型错误 : object of type 'generator' has no len()

Question

我该如何解决这个错误:
类型错误:“生成器”类型的对象没有 len()
谢谢!

for index, row in df_result.iterrows():
if index == 0:
    tempIndex = 0
else:
    if row['LEADID'] == df_result.at[tempIndex, 'LEADID']:
        if type(row['ID']) is str:
            df_result.at[tempIndex, 'ID'] = df_result.at[tempIndex, 'ID'] + "\n" + row['ID']
        if type(row['CREATEDBYID']) is str:
            df_result.at[tempIndex, 'CREATEDBYID'] = df_result.at[tempIndex, 'CREATEDBYID'] + "\n" + row['CREATEDBYID']
        if type(row['CREATEDDATE']) is str:
            df_result.at[tempIndex, 'CREATEDDATE'] = df_result.at[tempIndex, 'CREATEDDATE'] + "\n" + row['CREATEDDATE']
        if type(row['OLDVALUE']) is str:
            df_result.at[tempIndex, row['FIELD'] + "_OLDVALUE"] = df_result.at[tempIndex, row['FIELD'] + "_OLDVALUE"] + "\n" + row['OLDVALUE']
        if type(row['NEWVALUE']) is str:
            df_result.at[tempIndex, row['FIELD'] + "_NEWVALUE"] = df_result.at[tempIndex, row['FIELD'] + "_NEWVALUE"] + "\n" + row['NEWVALUE']
    else:
        resultIndexArr.append(tempIndex)
        tempIndex = index

        if tempIndex == len(df_result.iterrows()) - 1:
            resultIndexArr.append(tempIndex)

Answer 1

您不能使用 len在 df.iterrows ，因为它返回一个生成器——一个一次返回一个值的对象，并且没有长度(与 Python 序列不同)。
您可以使用 len(df.index)相反，根据 this S/O answer .