Filtering, querying a DataFrame

import pandas as pd

df = pd.read_csv('rates.csv', parse_dates=['Time'])
df.index = df['Time']
df

	Time	USD	JPY	BGN	CZK	DKK	GBP	CHF
Time
2024-01-17	2024-01-17	1.0877	160.65	1.9558	24.755	7.4586	0.85818	0.9406
2024-01-16	2024-01-16	1.0882	159.64	1.9558	24.710	7.4582	0.86078	0.9361
2024-01-15	2024-01-15	1.0945	159.67	1.9558	24.714	7.4590	0.86075	0.9351
2024-01-12	2024-01-12	1.0942	159.17	1.9558	24.689	7.4565	0.85950	0.9350
2024-01-11	2024-01-11	1.0987	159.71	1.9558	24.659	7.4568	0.86145	0.9338
...	...	...	...	...	...	...	...	...
2023-10-26	2023-10-26	1.0540	158.48	1.9558	24.714	7.4632	0.87170	0.9466
2023-10-25	2023-10-25	1.0576	158.55	1.9558	24.693	7.4639	0.87240	0.9474
2023-10-24	2023-10-24	1.0632	159.26	1.9558	24.659	7.4648	0.87025	0.9501
2023-10-23	2023-10-23	1.0597	158.91	1.9558	24.645	7.4634	0.87153	0.9461
2023-10-20	2023-10-20	1.0591	158.80	1.9558	24.704	7.4620	0.87213	0.9442

61 rows × 8 columns

df.query('USD > 1.105')

	Time	USD	JPY	BGN	CZK	DKK	GBP	CHF
Time
2023-12-28	2023-12-28	1.1114	156.57	1.9558	24.714	7.4545	0.8706	0.9302
2023-12-27	2023-12-27	1.1065	157.81	1.9558	24.673	7.4549	0.8683	0.9438

df.query('USD > 1.105 and JPY < 157')

	Time	USD	JPY	BGN	CZK	DKK	GBP	CHF
Time
2023-12-28	2023-12-28	1.1114	156.57	1.9558	24.714	7.4545	0.8706	0.9302

df.USD > 1.105 # boolean mask

Time
2024-01-17    False
2024-01-16    False
2024-01-15    False
2024-01-12    False
2024-01-11    False
              ...  
2023-10-26    False
2023-10-25    False
2023-10-24    False
2023-10-23    False
2023-10-20    False
Name: USD, Length: 61, dtype: bool

df[df.USD > 1.105]

	Time	USD	JPY	BGN	CZK	DKK	GBP	CHF
Time
2023-12-28	2023-12-28	1.1114	156.57	1.9558	24.714	7.4545	0.8706	0.9302
2023-12-27	2023-12-27	1.1065	157.81	1.9558	24.673	7.4549	0.8683	0.9438

mask1 = df.USD > 1.105
mask2 = df.JPY < 157
df[mask1 & mask2] # mask1 and mask2

	Time	USD	JPY	BGN	CZK	DKK	GBP	CHF
Time
2023-12-28	2023-12-28	1.1114	156.57	1.9558	24.714	7.4545	0.8706	0.9302

df[mask1 | mask2] # mask1 or mask2

	Time	USD	JPY	BGN	CZK	DKK	GBP	CHF
Time
2024-01-03	2024-01-03	1.0919	156.16	1.9558	24.675	7.4581	0.86470	0.9322
2024-01-02	2024-01-02	1.0956	155.68	1.9558	24.687	7.4551	0.86645	0.9305
2023-12-29	2023-12-29	1.1050	156.33	1.9558	24.724	7.4529	0.86905	0.9260
2023-12-28	2023-12-28	1.1114	156.57	1.9558	24.714	7.4545	0.87060	0.9302
2023-12-27	2023-12-27	1.1065	157.81	1.9558	24.673	7.4549	0.86830	0.9438
2023-12-22	2023-12-22	1.1023	156.66	1.9558	24.589	7.4560	0.86660	0.9417
2023-12-21	2023-12-21	1.0983	156.79	1.9558	24.481	7.4558	0.86805	0.9432
2023-12-18	2023-12-18	1.0918	155.95	1.9558	24.543	7.4549	0.86263	0.9480
2023-12-15	2023-12-15	1.0946	155.15	1.9558	24.477	7.4556	0.85833	0.9488
2023-12-14	2023-12-14	1.0919	154.80	1.9558	24.408	7.4566	0.85955	0.9490
2023-12-12	2023-12-12	1.0804	156.84	1.9558	24.420	7.4569	0.85928	0.9443
2023-12-08	2023-12-08	1.0777	155.53	1.9558	24.354	7.4558	0.85690	0.9438
2023-12-07	2023-12-07	1.0771	156.18	1.9558	24.356	7.4551	0.85750	0.9446