python - 在 Python 数据框中获取一天的一部分(早上、下午、晚上、晚上)

Question

这是我的数据框，我需要根据行值(早上、下午、晚上、晚上)的时间创建一个新列

这是我的代码

if ((prods['hour'] < 4) & (prods['hour'] > 8 )):
    prods['session'] = 'Early Morning'
elif ((prods['hour'] < 8) & (prods['hour'] > 12 )):
    prods['session'] = 'Morning'
elif ((prods['hour'] < 12) & (prods['hour'] > 16 )):
    prods['session'] = 'Noon'
elif ((prods['hour'] < 16) & (prods['hour'] > 20 )):
    prods['session'] = 'Eve'
elif ((prods['hour'] < 20) & (prods['hour'] > 24 )):
    prods['session'] = 'Night'
elif ((prods['hour'] < 24) & (prods['hour'] > 4 )):
    prods['session'] = 'Late Night'

这是我遇到的错误

ValueError Traceback (most recent call last) in ----> 1 if (prods['hour'] > 4 and prods['hour']< 8): 2 prods['session'] = 'Early Morning' 3 elif (prods['hour'] > 8 and prods['hour'] < 12): 4 prods['session'] = 'Morning' 5 elif (prods['hour'] > 12 and prods['hour'] < 16):

/anaconda3/lib/python3.7/site-packages/pandas/core/generic.py in nonzero(self) 1476 raise ValueError("The truth value of a {0} is ambiguous. " 1477 "Use a.empty, a.bool(), a.item(), a.any() or a.all()." -> 1478 .format(self.class.name)) 1479 1480 bool = nonzero

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

请帮忙

Answer 1

使用 cut 或自定义函数 and并且还改变了<至>和>至<=并且还为每个值添加 return :

prods = pd.DataFrame({'hour':range(1, 25)})

b = [0,4,8,12,16,20,24]
l = ['Late Night', 'Early Morning','Morning','Noon','Eve','Night']
prods['session'] = pd.cut(prods['hour'], bins=b, labels=l, include_lowest=True)

<小时/>

def f(x):
    if (x > 4) and (x <= 8):
        return 'Early Morning'
    elif (x > 8) and (x <= 12 ):
        return 'Morning'
    elif (x > 12) and (x <= 16):
        return'Noon'
    elif (x > 16) and (x <= 20) :
        return 'Eve'
    elif (x > 20) and (x <= 24):
        return'Night'
    elif (x <= 4):
        return'Late Night'

<小时/>

prods['session1'] = prods['hour'].apply(f)
print (prods)
    hour        session       session1
0      1     Late Night     Late Night
1      2     Late Night     Late Night
2      3     Late Night     Late Night
3      4     Late Night     Late Night
4      5  Early Morning  Early Morning
5      6  Early Morning  Early Morning
6      7  Early Morning  Early Morning
7      8  Early Morning  Early Morning
8      9        Morning        Morning
9     10        Morning        Morning
10    11        Morning        Morning
11    12        Morning        Morning
12    13           Noon           Noon
13    14           Noon           Noon
14    15           Noon           Noon
15    16           Noon           Noon
16    17            Eve            Eve
17    18            Eve            Eve
18    19            Eve            Eve
19    20            Eve            Eve
20    21          Night          Night
21    22          Night          Night
22    23          Night          Night
23    24          Night          Night