定義DataFrame
1. 按df中某列對(duì)行數(shù)據(jù)分組
df['data1'].groupby(df['key1']).sum()
2.按列表對(duì)行數(shù)據(jù)分組
key=[1,2,1,1,2]
df['data1'].groupby(key).mean()
3.按多個(gè)列對(duì)行數(shù)據(jù)分組
4.按列索引分組
5.將有多重索引的Series轉(zhuǎn)行成DataFrame
df1.unstack()
6.按類(lèi)型對(duì)列數(shù)據(jù)分組
df.groupby(df.dtypes, axis=1).sum()
定義DataFrame
df = pd.DataFrame(np.random.randint(1,10,(5,5)), columns=list('abcde'), index=['Alice', 'Bob','Candy', 'Dark','Emily'])
1.對(duì)列分組
mapping = {'a': 'red', 'b':'red', 'c': 'blue', 'd':'orange', 'e': 'blue'}
grouped = df.groupby(mapping, axis=1)
2.按索引長(zhǎng)度分組
