I have a pandas dataframe with a pair of columns where, on every row, one cell is a nan and the other is not. It looks like this: Var1 Var2 0 3 nan 1 8 nan 2 nan 6 3 4 nan 4 nan 2 5 nan 6 I would like to merge these two columns in one without the

Merging two non-overlapping pandas dataframe columns

I have a pandas dataframe with a pair of columns where, on every row, one cell is a nan and the other is not. It looks like this:

I would like to merge these two columns in one without the nans:

Any ideas?

Use fillna, setting values parameter to another Series.

df['Var1'].fillna(df['Var2'], inplace=True)
df['Var1']

#    Var1
# 0  3
# 1  8
# 2  6
# 3  4
# 4  2
# 5  6

JavaScript
​x
 
df['Var1'].fillna(df['Var2'], inplace=True)
df['Var1']
​
#    Var1
# 0  3
# 1  8
# 2  6
# 3  4
# 4  2
# 5  6
​