用逻辑选择行

Python 数据科学入门

Hillary Green-Lerman

Lead Data Scientist, Looker

继续调查

print(credit_records.head())

            suspect         location              date         item  price
0    Kirstine Smith   Groceries R Us   January 6, 2018     broccoli   1.25
1      Gertrude Cox  Petroleum Plaza   January 6, 2018  fizzy drink   1.90
2  Fred Frequentist   Groceries R Us   January 6, 2018     broccoli   1.25
3      Gertrude Cox   Groceries R Us  January 12, 2018     broccoli   1.25
4    Kirstine Smith    Clothing Club   January 9, 2018        shirt  14.25

Python 中的逻辑表达式

question = 12 * 8
solution = 96

question == solution

True

布尔值：True 和 False

其他类型的逻辑

, >=, <, <=

price = 2.25
price > 5.00

False

不等于

name = 'bayes'
name != 'Bayes'

True

在 DataFrame 中使用逻辑

credit_records.price > 20.00

0      False
1      False
2      False
3      False
4       True
5      False
...
99      True
100     True
101     True
102    False
103    False

在 DataFrame 中使用逻辑

credit_records[credit_records.price > 20.00]

                  suspect         location              date   item  price
28       Fred Frequentist    Clothing Club   January 3, 2018  dress  20.15
29         Kirstine Smith    Clothing Club   January 5, 2018  dress  20.15
33   Ronald Aylmer Fisher  Petroleum Plaza   January 7, 2018    gas  24.95
37       Fred Frequentist    Clothing Club   January 8, 2018  dress  20.15
40           Gertrude Cox    Clothing Club   January 1, 2018  dress  20.15
41         Kirstine Smith  Petroleum Plaza   January 5, 2018    gas  24.95
...

在 DataFrame 中使用逻辑

credit_records[credit_records.suspect == 'Ronald Aylmer Fisher']

                  suspect         location              date         item  price
7    Ronald Aylmer Fisher    Clothing Club   January 8, 2018        pants  12.05
8    Ronald Aylmer Fisher    Clothing Club  January 13, 2018        shirt  14.25
12   Ronald Aylmer Fisher  Petroleum Plaza  January 10, 2018      carwash  13.25
22   Ronald Aylmer Fisher   Groceries R Us  January 13, 2018         eggs   6.50
26   Ronald Aylmer Fisher      Burger Mart   January 8, 2018        fries   1.95
...

让我们来练习！

Python 数据科学入门