Contents

pandas 基本运算

import pandas as pd
import numpy as np

算术运算

df1 = pd.DataFrame(np.random.randn(10, 4), columns=["A", "B", "C", "D"])
df1

	A	B	C	D
0	-0.039197	-1.345397	1.231152	-1.209577
1	-0.146425	-0.126034	0.049097	-0.239117
2	-0.736525	0.855204	1.039200	-1.544436
3	-0.644882	-0.139244	-1.548867	-1.893190
4	0.763529	0.350332	-1.290519	-0.030608
5	0.523727	1.005206	-0.268476	-0.352177
6	1.667456	-0.197137	1.710659	0.412051
7	-1.872084	-1.234837	1.196401	-0.333764
8	0.390396	2.459068	-0.255654	-2.184972
9	2.191920	0.195064	-0.233379	1.106590

df2 = pd.DataFrame(np.random.randn(7, 3), columns=["A", "B", "C"])
df2

	A	B	C
0	-0.879968	-0.381367	1.288975
1	-0.088425	0.211976	0.194757
2	0.980227	-0.040865	0.656159
3	0.987874	-0.978989	-0.742291
4	0.859827	-0.987786	2.217203
5	-1.377002	-0.866408	-0.615638
6	-0.754354	0.127508	-0.240242

df1 * 5 + 2

	A	B	C	D
0	1.804017	-4.726986	8.155758	-4.047884
1	1.267876	1.369828	2.245483	0.804413
2	-1.682623	6.276020	7.195998	-5.722179
3	-1.224408	1.303778	-5.744335	-7.465951
4	5.817644	3.751659	-4.452595	1.846959
5	4.618635	7.026031	0.657621	0.239117
6	10.337280	1.014315	10.553293	4.060255
7	-7.360419	-4.174187	7.982006	0.331182
8	3.951981	14.295340	0.721729	-8.924858
9	12.959601	2.975322	0.833105	7.532952

1 / df1

	A	B	C	D
0	-25.512380	-0.743275	0.812248	-0.826735
1	-6.829445	-7.934342	20.368024	-4.182045
2	-1.357728	1.169312	0.962279	-0.647486
3	-1.550672	-7.181613	-0.645633	-0.528209
4	1.309708	2.854436	-0.774882	-32.671034
5	1.909392	0.994821	-3.724730	-2.839484
6	0.599716	-5.072613	0.584570	2.426885
7	-0.534164	-0.809823	0.835840	-2.996133
8	2.561500	0.406658	-3.911533	-0.457672
9	0.456221	5.126510	-4.284876	0.903677

df1 ** 4

	A	B	C	D
0	0.000002	3.276439	2.297451	2.140591e+00
1	0.000460	0.000252	0.000006	3.269227e-03
2	0.294272	0.534908	1.166261	5.689568e+00
3	0.172950	0.000376	5.755149	1.284627e+01
4	0.339861	0.015063	2.773688	8.777048e-07
5	0.075235	1.020988	0.005195	1.538303e-02
6	7.730677	0.001510	8.563543	2.882727e-02
7	12.282908	2.325086	2.048836	1.240955e-02
8	0.023229	36.566391	0.004272	2.279204e+01
9	23.083358	0.001448	0.002967	1.499503e+00

布尔运算

df1 = pd.DataFrame({"a": [1, 0, 1], "b": [0, 1, 1]}, dtype=bool)
df1

	a	b
0	True	False
1	False	True
2	True	True

df2 = pd.DataFrame({"a": [0, 1, 1], "b": [1, 1, 0]}, dtype=bool)
df2

	a	b
0	False	True
1	True	True
2	True	False

df1 & df2

	a	b
0	False	False
1	False	True
2	True	False

df1 | df2

	a	b
0	True	True
1	True	True
2	True	True

df1 ^ df2

	a	b
0	True	True
1	True	False
2	False	True

-df1

	a	b
0	False	True
1	True	False
2	False	False

Last updated on Mar 4, 2022