pandas：用另一个字符串替换字符串

Posted 2023-03-11

【中文标题】pandas：用另一个字符串替换字符串

【英文标题】：pandas: replace string with another string

【发布时间】：2017-01-28 21:26:50

【问题描述】：

我有以下数据框

    prod_type
0   responsive
1   responsive
2   respon
3   r
4   respon
5   r
6   responsive

我想把respon和r换成responsive，所以最终的数据框是

    prod_type
0   responsive
1   responsive
2   responsive
3   responsive
4   responsive
5   responsive
6   responsive

我尝试了以下方法，但没有成功：

df['prod_type'] = df['prod_type'].replace('respon' : 'responsvie', regex=True)
df['prod_type'] = df['prod_type'].replace('r' : 'responsive', regex=True)

【参考方案1】：

按照jezrael的回答，可以设置inplace=True改变数据框：

df = pd.DataFrame(
    'prod_type':['responsive','responsive','respon','r','respon','r','responsive'],
    columns=['prod_type'])

df.replace('prod_type': 'respon': 'responsive', 'r': 'responsive', inplace=True)
df
    prod_type
0  responsive
1  responsive
2  responsive
3  responsive
4  responsive
5  responsive
6  responsive

【参考方案2】：

或者，您可以使用带有 lambda 语法的 apply 函数

df['prod_type'] = df['prod_type'].apply(lambda x: x.replace('respon', 'responsvie'))

【参考方案3】：

replace dictionary 的解决方案：

df['prod_type'] = df['prod_type'].replace('respon':'responsive', 'r':'responsive')
print (df)
    prod_type
0  responsive
1  responsive
2  responsive
3  responsive
4  responsive
5  responsive
6  responsive

如果需要将列中的所有值设置为某个string：

df['prod_type'] = 'responsive' 

【参考方案4】：

如果df['prod_type'] 中的所有项目都相同的其他解决方案：

df['prod_type'] = ['responsive' for item in df['prod_type']]
In[0]: df
Out[0]:
prod_type
0  responsive
1  responsive
2  responsive
3  responsive
4  responsive
5  responsive
6  responsive

【参考方案5】：

您无需在此处传递 regex=True，因为这将查找部分匹配项，因为您在完全匹配之后只需将参数作为单独的 args 传递：

In [7]:
df['prod_type'] = df['prod_type'].replace('respon' ,'responsvie')
df['prod_type'] = df['prod_type'].replace('r', 'responsive')
df

Out[7]:
    prod_type
0  responsive
1  responsive
2  responsvie
3  responsive
4  responsvie
5  responsive
6  responsive