import pandas as pd
# 建立兩個 DataFrame
df1 = pd.DataFrame({‘A’: [1, 2, 3], ‘B’: [4, 5, 6]})
df2 = pd.DataFrame({‘A’: [4, 5, 6], ‘B’: [7, 8, 9]})
# 將兩個 DataFrame 沿著行方向合併,並保留原始索引
concat1 = pd.concat([df1, df2])
print(“concat1(無額外參數):\n”,concat1)
# 將兩個 DataFrame 沿著行方向合併,並重新設置索引,且不保留原始索引
concat2 = pd.concat([df1, df2]).reset_index(drop=True)
print(“\nconcat2(reset_index):\n”,concat2)
# 將兩個 DataFrame 沿著行方向合併,並忽略原始索引,重新設置索引
concat3 = pd.concat([df1, df2], ignore_index=True)
print(“\nconcat3(ignore_index):\n”,concat3)
![Python:如何用pandas.concat() 合併兩個DataFrame並重置index? pd.concat([df1, df2]) .reset_index(drop=True) ; pd.concat([df1, df2], ignore_index=True) - 儲蓄保險王](https://savingking.com.tw/wp-content/uploads/2023/03/20230311123232_5.png)
輸出結果(注意左邊的index):
![Python:如何用pandas.concat() 合併兩個DataFrame並重置index? pd.concat([df1, df2]) .reset_index(drop=True) ; pd.concat([df1, df2], ignore_index=True) - 儲蓄保險王](https://savingking.com.tw/wp-content/uploads/2023/03/20230311123415_47.png)
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