Pandas：DataFrame 中的 DataFrame
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/17954520/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Pandas: DataFrame within DataFrame
提问by jorge.santos
I need to create a DataFramethat contains columns of DataFrames. The DataFramesthat go in the column have different sizes and I am getting a StopIterationexception. This doesn't happen, when the DataFramesare of the same size. I know a Panelis more suitable for this, but I need a DataFramein this case.
我需要创建一个DataFrame包含DataFrames. 在DataFrames那走在列有不同的大小，我得到一个StopIteration例外。当DataFrames大小相同时，这不会发生。我知道 aPanel更适合于此，但DataFrame在这种情况下我需要 a 。
a=pd.DataFrame({'cat1':['one','two','three'],'cat2':['four','five','six']})
b=pd.DataFrame({'cat1':['ten','eleven'],'cat2':['twelve','thirteen']})
pd.DataFrame({'col1':{'row1':a,'row2':b}})
If I remove the 'three' and 'six' items from 'cat1', 'cat2' respectively, then this works fine. Any idea how I can achieve this?
如果我分别从“cat1”、“cat2”中删除“三个”和“六个”项目，那么这可以正常工作。知道我如何实现这一目标吗？
采纳答案by Jeff
this is not a good idea, you lose all efficiency because things are treated as objectdtype and operations will be quite slow (as operations cannot be done via c-level base types, like float/int). Better is to use a multi-level index, which can easily encompass what I think you want
这不是一个好主意，您会失去所有效率，因为事情被视为objectdtype 并且操作将非常缓慢（因为操作不能通过 c 级基本类型完成，例如 float/int）。更好的是使用多级索引，它可以轻松包含我认为你想要的
In [20]: a
Out[20]:
cat1 cat2
0 one four
1 two five
2 three six
In [21]: b
Out[21]:
cat1 cat2
0 ten twelve
1 eleven thirteen
In [22]: pd.concat([ a, b ], keys={ 'row1' : a, 'row2' : b })
Out[22]:
cat1 cat2
row1 0 one four
1 two five
2 three six
row2 0 ten twelve
1 eleven thirteen
