Gấu trúc coi Không và NaN về cơ bản có thể hoán đổi cho nhau để chỉ ra các giá trị bị thiếu hoặc null. Để tạo thuận lợi cho quy ước này, có một số chức năng hữu ích để phát hiện, xóa và thay thế các giá trị null trong Pandas DataFrame
- isnull[]
- có giá trị[]
- dropna[]
- điền []
- thay thế[]
- nội suy[]
Trong bài viết này, chúng tôi đang sử dụng tệp CSV, để tải xuống tệp CSV đã sử dụng, hãy nhấp vào đây
Kiểm tra các giá trị bị thiếu bằng isnull[] và notnull[]
Để kiểm tra các giá trị còn thiếu trong Pandas DataFrame, chúng tôi sử dụng hàm isnull[] và notnull[]. Cả hai chức năng đều giúp kiểm tra xem một giá trị có phải là NaN hay không. Các chức năng này cũng có thể được sử dụng trong Pandas Series để tìm các giá trị null trong một chuỗi
Kiểm tra các giá trị bị thiếu bằng cách sử dụng isnull[]
Để kiểm tra các giá trị null trong Pandas DataFrame, chúng tôi sử dụng hàm isnull[] hàm này trả về khung dữ liệu của các giá trị Boolean là True cho các giá trị NaN. Mã số 1.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______4import
4# importing pandas as pd
4import
6import
7
# importing pandas as pd
9import
9pandas as pd
0_______2_______1# importing pandas as pd
4pandas as pd
3# importing pandas as pd
4pandas as pd
5pandas as pd
6
pandas as pd
7
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
# importing numpy as np
3
# importing numpy as np
4
Đầu ra.
con trăn
# importing numpy as np
5
import
pandas as pd
# importing numpy as np
8
# importing numpy as np
9
import
0=
import
2
# importing numpy as np
8
import
4
import
5_______8_______ import
7
# importing numpy as np
8
import
9
numpy as np
0
numpy as np
1
Đầu ra. Như thể hiện trong hình ảnh đầu ra, chỉ những hàng có Giới tính = NULL được hiển thị.
Kiểm tra các giá trị bị thiếu bằng cách sử dụng notnull[]
Để kiểm tra các giá trị null trong Pandas Dataframe, chúng tôi sử dụng hàm notnull[] hàm này trả về khung dữ liệu của các giá trị Boolean là Sai đối với các giá trị NaN. Mã số 3.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______4import
4# importing pandas as pd
4import
6import
7
# importing pandas as pd
9import
9pandas as pd
0_______2_______1# importing pandas as pd
4pandas as pd
3# importing pandas as pd
4pandas as pd
5pandas as pd
6
=
8
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
# importing pandas as pd
04
# importing pandas as pd
05
Đầu ra.
con trăn
# importing numpy as np
5
import
pandas as pd
# importing numpy as np
8
# importing numpy as np
9
import
0=
import
2
# importing numpy as np
8
import
4
import
5_______8_______ # importing pandas as pd
18
# importing numpy as np
8
import
9
# importing pandas as pd
21
numpy as np
1
Đầu ra. Như thể hiện trong hình ảnh đầu ra, chỉ những hàng có Giới tính = KHÔNG NULL được hiển thị.
Điền các giá trị còn thiếu bằng cách sử dụng fillna[], thay thế[] và nội suy[]
Để điền các giá trị null vào bộ dữ liệu, chúng tôi sử dụng hàm fillna[], replace[] và interpolate[], các hàm này thay thế các giá trị NaN bằng một số giá trị của riêng chúng. Tất cả các chức năng này giúp điền vào các giá trị null trong bộ dữ liệu của DataFrame. Hàm nội suy [] về cơ bản được sử dụng để điền các giá trị NA vào khung dữ liệu nhưng nó sử dụng nhiều kỹ thuật nội suy khác nhau để điền các giá trị còn thiếu thay vì mã hóa cứng giá trị. Mã số 1. Điền giá trị null với một giá trị duy nhất
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______4import
4# importing pandas as pd
4import
6import
7
# importing pandas as pd
9import
9pandas as pd
0_______2_______1# importing pandas as pd
4pandas as pd
3# importing pandas as pd
4pandas as pd
5pandas as pd
6
# importing pandas as pd
59
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
# importing pandas as pd
65
# importing pandas as pd
66# importing pandas as pd
67# importing numpy as np
2
Đầu ra.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______4import
4# importing pandas as pd
4import
6import
7
# importing pandas as pd
9import
9pandas as pd
0_______2_______1# importing pandas as pd
4pandas as pd
3# importing pandas as pd
4pandas as pd
5pandas as pd
6
# importing pandas as pd
59
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
import
11
import
12
import
13=
import
15# importing numpy as np
2
Đầu ra.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______4import
4# importing pandas as pd
4import
6import
7
# importing pandas as pd
9import
9pandas as pd
0_______2_______1# importing pandas as pd
4pandas as pd
3# importing pandas as pd
4pandas as pd
5pandas as pd
6
# importing pandas as pd
59
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
import
59
import
13_______8_______import
62# importing numpy as np
2
Đầu ra.
con trăn
# importing numpy as np
5
import
pandas as pd
# importing numpy as np
8
# importing numpy as np
9
import
0=
import
2
import
72
import
73
import
74_______1_______75import
76import
77import
78
con trăn
# importing numpy as np
5
import
pandas as pd
# importing numpy as np
8
# importing numpy as np
9
import
0=
import
2
import
87
import
88=
import
90# importing numpy as np
2
import
0
Đầu ra.
con trăn
# importing numpy as np
5
import
pandas as pd
# importing numpy as np
8
# importing numpy as np
9
import
0=
import
2
import
72
import
73
import
74_______1_______75import
76import
77import
78
Đầu ra.
con trăn
# importing numpy as np
5
import
pandas as pd
# importing numpy as np
8
# importing numpy as np
9
import
0=
import
2
# importing numpy as np
8
pandas as pd
17
pandas as pd
18=
pandas as pd
20_______8_______ pandas as pd
22pandas as pd
23# importing numpy as np
2
Đầu ra.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
8
pandas as pd
29
pandas as pd
8=
pandas as pd
32_______2_______33_______0_______4pandas as pd
35# importing pandas as pd
4pandas as pd
37# importing pandas as pd
4pandas as pd
39# importing pandas as pd
4pandas as pd
41# importing pandas as pd
8
pandas as pd
43pandas as pd
44pandas as pd
39# importing pandas as pd
4pandas as pd
47# importing pandas as pd
4pandas as pd
49# importing pandas as pd
4pandas as pd
51# importing pandas as pd
4pandas as pd
39# importing pandas as pd
8
pandas as pd
43pandas as pd
56pandas as pd
57# importing pandas as pd
4pandas as pd
59# importing pandas as pd
4pandas as pd
39# importing pandas as pd
4pandas as pd
51# importing pandas as pd
4pandas as pd
65# importing pandas as pd
8
pandas as pd
43pandas as pd
68pandas as pd
69# importing pandas as pd
4pandas as pd
51# importing pandas as pd
4pandas as pd
39# importing pandas as pd
4pandas as pd
39# importing pandas as pd
4pandas as pd
77pandas as pd
78
# importing numpy as np
8
pandas as pd
80
pandas as pd
8
con trăn
pandas as pd
82
pandas as pd
83=
___pandas as pd
85_______2_______86_______8_______2_______88# importing numpy as np
2
Đầu ra.
Loại bỏ các giá trị bị thiếu bằng cách sử dụng dropna[]
Để loại bỏ các giá trị null khỏi khung dữ liệu, chúng tôi đã sử dụng hàm dropna[] hàm này loại bỏ các Hàng/Cột của bộ dữ liệu có giá trị Null theo các cách khác nhau. Mã số 1. Xoá hàng có ít nhất 1 giá trị null.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______6import
4# importing pandas as pd
4import
6# importing pandas as pd
8
# importing pandas as pd
9import
9# importing pandas as pd
2_______3_______20_______0_______4pandas as pd
1# importing pandas as pd
4pandas as pd
3_______0_______4pandas as pd
5# importing pandas as pd
8
# importing pandas as pd
9# importing numpy as np
29# importing numpy as np
30# importing numpy as np
31pandas as pd
6
# importing pandas as pd
59
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
# importing numpy as np
8
pandas as pd
8
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1_______0_______2# importing pandas as pd
3# importing pandas as pd
4# importing pandas as pd
5# importing pandas as pd
6# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______6import
4# importing pandas as pd
4import
6# importing pandas as pd
8
# importing pandas as pd
9import
9# importing pandas as pd
2_______3_______20_______0_______4pandas as pd
1# importing pandas as pd
4pandas as pd
3_______0_______4pandas as pd
5# importing pandas as pd
8
# importing pandas as pd
9# importing numpy as np
29# importing numpy as np
30# importing numpy as np
31pandas as pd
6
# importing pandas as pd
59
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
# importing numpy as np
90
# importing numpy as np
91
Đầu ra.
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1# importing pandas as pd
2# importing pandas as pd
3import
05# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______6import
4# importing pandas as pd
4import
6# importing pandas as pd
8
# importing pandas as pd
9import
9# importing pandas as pd
2_______3_______20_______0_______6pandas as pd
3# importing pandas as pd
4pandas as pd
5_______0_______8
# importing pandas as pd
9# importing numpy as np
29# importing numpy as np
30# importing numpy as np
31pandas as pd
6
# importing pandas as pd
59
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
# importing numpy as np
8
pandas as pd
8
con trăn
# importing pandas as pd
import
pandas as pd
# importing numpy as np
import
numpy as np
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1# importing pandas as pd
2# importing pandas as pd
3import
05# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______6import
4# importing pandas as pd
4import
6# importing pandas as pd
8
# importing pandas as pd
9import
9# importing pandas as pd
2_______3_______20_______0_______6pandas as pd
3# importing pandas as pd
4pandas as pd
5_______0_______8
# importing pandas as pd
9# importing numpy as np
29# importing numpy as np
30# importing numpy as np
31pandas as pd
6
pandas as pd
8=
# importing numpy as np
0dict
# importing numpy as np
2
import
83
import
84=
import
86# importing numpy as np
2
Đầu ra.
con trăn
# importing pandas as pd
import
pandas as pd
import
91
# importing numpy as np
import
numpy as np
import
91
# dictionary of lists
dict
=
# importing pandas as pd
0# importing pandas as pd
1# importing pandas as pd
2# importing pandas as pd
3import
05# importing pandas as pd
7# importing pandas as pd
8
# importing pandas as pd
9import
0import
1_______1_______2_______0_______6import
4# importing pandas as pd
4import
6# importing pandas as pd
8
# importing pandas as pd
9import
9# importing pandas as pd
2_______3_______20_______0_______6pandas as pd
3# importing pandas as pd
4pandas as pd
5_______0_______8
# importing pandas as pd
9# importing numpy as np
29# importing pandas as pd
2_______5_______27# importing pandas as pd
4numpy as np
29# importing pandas as pd
4numpy as np
31# importing pandas as pd
4# importing numpy as np
31pandas as pd
6