Pandas
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引入:import pandas as pd
常也需import numpy as np
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create df:
df = pd.DataFrame(...)
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selection:
選列:df['A'] 選行:df[0:3] 多維:df.loc[:, ['A', 'B']]或df.iloc[:, 0:2] 選值:df.at[2,'A']或者df.iloc[2,0]
- 處理空值:df.dropna df.fillna
- apply funcs:df.apply(lambda)
- SQL-like join: pd.merge(A, B, on="...")
- 文件:df.to_csv("...") pd.read_csv("...")