Lesson 08: pandas 공부 3단계

강의영상

imports

import numpy as np
import pandas as pd

pandas 공부 3단계: 필터링

np.random.seed(43052)
att = np.random.choice(np.arange(10,21)*5,20)
rep = np.random.choice(np.arange(5,21)*5,20)
mid = np.random.choice(np.arange(0,21)*5,20)
fin = np.random.choice(np.arange(0,21)*5,20)
key = ['2022-12'+str(s) for s in np.random.choice(np.arange(300,501),20,replace=False)]
df = pd.DataFrame({'att':att,'rep':rep,'mid':mid,'fin':fin},index=key)
df.head()

	att	rep	mid	fin
2022-12380	65	55	50	40
2022-12370	95	100	50	80
2022-12363	65	90	60	30
2022-12488	55	80	75	80
2022-12312	80	30	30	100

query (\(\star\))

- 예제1: att==90 and fin>30

df.query('att ==90 and fin >30')

	att	rep	mid	fin
2022-12354	90	90	80	90

- 예제2: att<rep and mid<fin

df.query('att<rep and mid<fin')

	att	rep	mid	fin
2022-12370	95	100	50	80
2022-12488	55	80	75	80
2022-12458	50	55	15	85

- 예제3: att < rep < 80

df.query('att<rep<80')

	att	rep	mid	fin
2022-12318	55	75	35	25
2022-12458	50	55	15	85

- 예제4: 50 < att <= 90 and mid < fin

df.query('50<att<=90 and mid<fin')

	att	rep	mid	fin
2022-12488	55	80	75	80
2022-12312	80	30	30	100
2022-12463	65	45	45	90
2022-12452	65	55	15	45
2022-12354	90	90	80	90

- 예제5: (mid+fin)/2 >=60

df.query('(mid+fin)/2>=60')

	att	rep	mid	fin
2022-12370	95	100	50	80
2022-12488	55	80	75	80
2022-12312	80	30	30	100
2022-12463	65	45	45	90
2022-12396	95	30	30	95
2022-12354	90	90	80	90

- 예제6: att > mean(att)

df.query('att> att.mean()')

	att	rep	mid	fin
2022-12370	95	100	50	80
2022-12312	80	30	30	100
2022-12377	75	40	100	15
2022-12400	95	65	20	10
2022-12469	90	80	80	20
2022-12432	95	95	45	0
2022-12443	95	55	15	35
2022-12396	95	30	30	95
2022-12354	90	90	80	90

query 사용금지