原文链接：https://github.com/jackfrued/Python-100-Days
import numpy as np
import pandas as pd
from pandas import Series,DataFrame
s = Series(np.random.randint(0,150,size = 100),index = np.arange(10,110),dtype=np.int16,name = 'Python')
s
》》》 10 34
11 111
12 113
13 103
14 147
15 63
16 11
17 130
18 38
19 17
20 32
21 112
22 75
23 68
24 124
25 138
26 56
27 1
28 88
29 113
30 63
...
90 110
91 144
92 40
93 3
94 3
95 59
96 97
97 64
98 126
99 94
100 20
101 107
102 59
103 146
104 83
105 59
106 25
107 0
108 78
109 93
Name: Python, Length: 100, dtype: int16
s[0]
》》》 KeyError: 0
s[10]
》》》 34
s[[10,20]]
》》》 10 34
20 32
Name: Python, dtype: int16
s[10:20]
》》》 20 32
21 112
22 75
23 68
24 124
25 138
26 56
27 1
28 88
29 113
Name: Python, dtype: int16
s[::2]
》》》 10 34
12 113
14 147
16 11
18 38
20 32
22 75
24 124
26 56
28 88
30 63
...
80 127
82 110
84 127
86 33
88 134
90 110
92 40
94 3
96 97
98 126
100 20
102 59
104 83
106 25
108 78
Name: Python, dtype: int16
s[::-2]
》》》 109 93
107 0
105 59
103 146
101 107
99 94
97 64
95 59
93 3
91 144
...
31 42
29 113
27 1
25 138
23 68
21 112
19 17
17 130
15 63
13 103
11 111
Name: Python, dtype: int16
s.loc[10]
》》》 34
s.loc[[10,20]]
》》》 10 34
20 32
Name: Python, dtype: int16
s.loc[10:20]
》》》 10 34
11 111
12 113
13 103
14 147
15 63
16 11
17 130
18 38
19 17
20 32
Name: Python, dtype: int16
s.loc[::2]
》》》 10 34
12 113
14 147
16 11
18 38
20 32
22 75
24 124
26 56
28 88
30 63
...
90 110
92 40
94 3
96 97
98 126
100 20
102 59
104 83
106 25
108 78
Name: Python, dtype: int16
s.loc[::-2]
》》》 109 93
107 0
105 59
103 146
101 107
99 94
97 64
95 59
93 3
91 144
...
31 42
29 113
27 1
25 138
23 68
21 112
19 17
17 130
15 63
13 103
11 111
Name: Python, dtype: int16
s.index
》》》 Int64Index([ 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100,
101, 102, 103, 104, 105, 106, 107, 108, 109],
dtype='int64')
s.iloc[0]
》》》 34
s.iloc[[0,10]]
》》》 10 34
20 32
Name: Python, dtype: int16
s.iloc[0:20]
》》》 10 34
11 111
12 113
13 103
14 147
15 63
16 11
17 130
18 38
19 17
20 32
21 112
22 75
23 68
24 124
25 138
26 56
27 1
28 88
29 113
Name: Python, dtype: int16
s.iloc[::-2]
》》》 109 93
107 0
105 59
103 146
101 107
99 94
97 64
95 59
93 3
91 144
...
29 113
27 1
25 138
23 68
21 112
19 17
17 130
15 63
13 103
11 111
Name: Python, dtype: int16
df = DataFrame(data = np.random.randint(0,150,size= (10,3)),index=list('ABCDEFHIJK'),columns=['Python','En','Math'])
df
df['A']
》》》 KeyError: 'A'
df['Python']
》》》 A 103
B 135
C 13
D 47
E 89
F 64
H 48
I 16
J 122
K 60
Name: Python, dtype: int32
df[['Python','En']]
df['Python':'Math']
df['A':'D']
df.loc['Python']
》》》 KeyError: 'Python'
df.loc['A']
》》》 Python 103
En 56
Math 98
Name: A, dtype: int32
df.loc[['A','H']]
df.loc['A':'E']
df.loc[::2]
df.loc[::-2]
df.iloc['A']
》》》 TypeError: Cannot index by location index with a non-integer key
df.iloc[0]
》》》 Python 103
En 56
Math 98
Name: A, dtype: int32
df.iloc[[0,5]]
df.iloc[0:5]
df.iloc[::-2]
df
df.iloc[::2,1:]
