Assertion Error in columns in DataFrame with hierarchical indexing
I pushed a fix for this yesterday. Here's the new behavior on github master:
In [1]: pastefrom pandas import DataFramef = DataFrame({'a': ['1','2','3'], 'b': ['2','3','4']})f.columns = [['level1 item1', 'level1 item2'],['', 'level2 item2'], ['level3 item1', 'level3 item2']]f## -- End pasted text --Out[1]: level1 item1 level1 item2 level2 item2 level3 item1 level3 item20 1 21 2 32 3 4In [2]: f['level1 item1']Out[2]: level3 item10 11 22 3