I have a Pandas Dataframe as below: itm Date Amount 67 420 2012-09-30 00:00:00 65211 68 421 2012-09-09 00:00:00 29424 69 421 2012-09-16 00:00:00 29877 70 421 2012-09-23 00:00:00 30990 71 421 2012-09-30 00:00:00 61303 72 485 2012-09-09 00:00:00 71781 73 485 2012-09-16 00:00:00 NaN 74 485 2012-09-23 00:00:00 11072 75 485 2012-09-30 00:00:00 113702 76 489 2012-09-09 00:00:00 64731 77 489 2012-09-16 00:00:00 NaN When I try to apply a function to the Amount column, I get the following error: ValueError: cannot convert float NaN to integer I have tried applying a function using math.isnan, pandas' .replace method, .sparse data attribute from pandas 0.9, if NaN == NaN statement in a function; I have also looked at this Q/A; none of them works. How do I do it? Continue reading...