使用 if 语句删除列，然后添加异常答案

【问题标题】：Dropping Columns with if statements, then adding exception使用 if 语句删除列，然后添加异常
【发布时间】：2022-07-06 02:58:57
【问题描述】：

我有这段代码通过 csv，为我找到有意义的列，然后删除不在列表中的列。它工作得很好，但我希望它删除所有未找到的列，除了一个名为“MATNR”的列。除了“MATNR”之外，我可以在 drop 语句中添加什么来允许我删除所有不需要的列？

# Import Data Quality Rules (useful attributes)
rexp = re.compile('\.([A-Z]+)')
found = []

with open('DataRules.csv') as f:
    for line in f:
        found.extend(rexp.findall(line))

# Get rid of columns that are not mentioned in rules (except MATNR)
df.drop(columns=([col for col in df if col not in found]), inplace=True)

# Get rid of duplicated rows
df = df.drop_duplicates()

【问题讨论】：

您可以通过说df[found] 仅提取您想要的列。要添加 MATNR，请执行 df[found+['MATNR']]。
found.remove('MATNR')?
[col for col in df if col not in found and col != 'MATNR']
df[['MATNR']]

标签： python pandas

【解决方案1】：

# Import Data Quality Rules (useful attributes)
rexp = re.compile('\.([A-Z]+)')
found = []

with open('DataRules.csv') as f:
    for line in f:
        found.extend(rexp.findall(line))

# Get rid of columns that are not mentioned in rules (except MATNR)
df.drop(columns=([col for col in df if col not in found and col != 'MATNR']), inplace=True)

# Get rid of duplicated rows
df = df.drop_duplicates()

【讨论】：