从数据框中的列中提取星期几并放入另一列

Question

# Give day of the week
def DOW(df):
    DOW = pd.Series(datetime.datetime.strptime(df['indx'],'%Y%m%d').strftime('%A'))
    df = df.join(DOW)
    return df

我从另一个脚本调用这个函数，因为 d 是我传递给函数 DOW 的数据帧

 d = TA.DOW(d)

它抛出错误。什么可以解决同样的问题

DOW=pd.Series(datetime.datetime.strptime(df['indx'],'%Y%m%d').strftime('%A'))
TypeError: must be string, not Series

Answer 1

我想你可以先转换列 indx to_datetime and then use dt.strftime as mentioned :

print df
       indx  Value
0  20020101   3.00
1  20020102   3.50
2  20020103   3.30
3  20100101   4.96
4  20100102   4.98

df['new'] = pd.to_datetime(df['indx'], format='%Y%m%d').dt.strftime('%A') 
print df
       indx  Value        new
0  20020101   3.00    Tuesday
1  20020102   3.50  Wednesday
2  20020103   3.30   Thursday
3  20100101   4.96     Friday
4  20100102   4.98   Saturday

从数据框中的列中提取星期几并放入另一列

Extract day of the week from column in dataframe and put in another column

python

datetime

dayofweek

pandas