pydata/pandas — Issue #892: Weird None /nan behaviour
Author: arthurgerigk
Created: 2012-03-09 16:32:02+00:00
State: open

Somehow I can't set single NaN entries to be None, but I can set a whole column of NaN entries to a column of None entries. ( x[1].ix[3]=None doesnt work either)

>>> from pandas import *
>>> x = DataFrame(columns=[0,1], index=[3,4])
>>> x
0 1
3 NaN NaN
4 NaN NaN

>>> x[0]= [None,None] # this works fine
>>> x
0 1
3 None NaN
4 None NaN

>>> x[1][3]=None # this has no effect and is my issue
>>> x
0 1
3 None NaN
4 None NaN