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我无法合并dataframes和无法理解为什么:类型错误:不能在非类别项追加到CategoricalIndex
简单的数据帧
df1 = pd.DataFrame({'id': np.random.randint(1,5,100),
'c': np.random.random(100),
's': np.random.random(100)})
分组以3个groupes
grouped = pd.qcut(df1.c, 3)
df_grouped = df1.groupby([grouped, 'id'])
df_cross = df_grouped['s'].sum()
df_unstacked = df_cross.unstack(level=0)
df_unstacked
日期:
c [0.018, 0.372] (0.372, 0.771] (0.771, 0.995]
id
1 3.081537 6.329819 3.386422
2 4.270542 2.553301 3.778536
3 3.125476 2.525016 3.013912
4 5.762223 3.763183 7.953551
其次简单的数据框:
df2 = pd.DataFrame({'one': range(5),
'two': np.random.randint(1,5,5),
'three': ['a', 'a', 'a', 'b', 'b']})
one three two
0 0 a 4
1 1 a 2
2 2 a 1
3 3 b 2
4 4 b 2
试图合并这两个:
pd.merge(df_unstacked, df2, left_index=True, right_on='one')
我希望:
c [0.018, 0.372] (0.372, 0.771] (0.771, 0.995] one three two
id
1 3.081537 6.329819 3.386422 1 a 2
2 4.270542 2.553301 3.778536 2 a 1
3 3.125476 2.525016 3.013912 3 b 2
4 5.762223 3.763183 7.953551 4 b 2
但我得到的类型错误:
TypeError: cannot append a non-category item to a CategoricalIndex
而且,试图在df_unsta上重置reset_index() cked,给出TypeError:
TypeError: cannot insert an item into a CategoricalIndex that is not already an existing category
制作.copy()没有帮助:)该怎么办?
p.s.熊猫0.17.1
你的'df_unstacked'列是绝对的,你如何看待'concat'?这是出现错误的地方 – EdChum
Thanx EdChum,现在我明白了这个问题至少:) – arvyzu
我不确定你可以绕过这个说实话,除非你用str代表覆盖列,然后合并 – EdChum