如何將包含np數組的2列連接到數據框中的新列

Question

原始數據框

A                      B
np.array([1, 2, 3])    np.array([4, 5, 6])
np.array([7, 8, 9])    np.array([9, 10, 11])

希望它成為

A                      B                         C
np.array([1, 2, 3])    np.array([4, 5, 6])       np.array([1, 2, 3, 4, 5, 6])
np.array([7, 8, 9])    np.array([9, 10, 11])     np.array([7, 8, 9, 9, 10, 11])

如何實現呢？

Answer 1

選項1：

In [66]: df['C'] = [np.append(*x) for x in df[['A', 'B']].values]

In [67]: df
Out[67]:
           A            B                     C
0  [1, 2, 3]    [4, 5, 6]    [1, 2, 3, 4, 5, 6]
1  [7, 8, 9]  [9, 10, 11]  [7, 8, 9, 9, 10, 11]

選項2： df['C'] = [np.concatenate(x) for x in df[['A', 'B']].values]

選項3： df['C'] = map(np.concatenate, df[['A', 'B']].values)

測試

In [69]: df.loc[0, 'C']
Out[69]: array([1, 2, 3, 4, 5, 6])