pandas Appending to DataFrame Append a DataFrame to another DataFrame
Example
Let us assume we have the following two DataFrames:
In [7]: df1
Out[7]:
A B
0 a1 b1
1 a2 b2
In [8]: df2
Out[8]:
B C
0 b1 c1
The two DataFrames are not required to have the same set of columns. The append method does not change either of the original DataFrames. Instead, it returns a new DataFrame by appending the original two. Appending a DataFrame to another one is quite simple:
In [9]: df1.append(df2)
Out[9]:
A B C
0 a1 b1 NaN
1 a2 b2 NaN
0 NaN b1 c1
As you can see, it is possible to have duplicate indices (0 in this example). To avoid this issue, you may ask Pandas to reindex the new DataFrame for you:
In [10]: df1.append(df2, ignore_index = True)
Out[10]:
A B C
0 a1 b1 NaN
1 a2 b2 NaN
2 NaN b1 c1
