I\'ve created a Pandas DataFrame
df = DataFrame(index=[\'A\',\'B\',\'C\'], columns=[\'x\',\'y\'])
and got this
x y A NaN
In my example i just change it in selected cell
for index, row in result.iterrows(): if np.isnan(row['weight']): result.at[index, 'weight'] = 0.0
'result' is a dataField with column 'weight'