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python - 标签合并数据框

问题描述

我已经将两个 DataFrame 合二为一，但不知道如何标记“state_x”和“state_y”tp“西海岸和“东海岸”。我稍后会绘制它们。

到目前为止我所拥有的：


    West_quakes = pd.DataFrame({'state':  ['California', 'Oregon', 'Washington', 'Alaska'], 
                    'Occurrences':  [18108, 376, 973, 12326]})
East_quakes = pd.DataFrame({'state': ['Maine', 'New Hampshire', 'Massachusetts',  
                        'Connecticut', 'New York', 'New Jersey', 'Pennsylvania',  'Maryland', 
                        'Virginia', 'North Carolina', 'South Carolina', 'Georgia', 'Florida'],
                        'Occurrences': [36, 13, 10, 5, 35, 10, 14, 2, 28, 17, 32, 14, 1]})

West_quakes.reset_index(drop=True).merge(East_quakes.reset_index(drop=True), left_index=True, right_index=True)

输出：


state_x Occurrences_x   state_y Occurrences_y
0   California  18108   Maine   36
1   Oregon  376 New Hampshire   13
2   Washington  973 Massachusetts   10
3   Alaska  12326   Connecticut 5

我尝试过的其他合并方法但会导致语法错误，例如：

West_quake.set_index('West Coast', inplace=True)
East_quake.set_index('East Coast', inplace=True)

在谷歌上搜索并在这里搜索后，我真的迷路了。

任何帮助将不胜感激。

谢谢你。

标签： pythonpandasmerge

解决方案

也许您正在寻找concat：

pd.concat((West_quakes, East_quakes))

给出：

             state  Occurrences
0       California        18108
1           Oregon          376
2       Washington          973
3           Alaska        12326
0            Maine           36
1    New Hampshire           13
2    Massachusetts           10
3      Connecticut            5
4         New York           35
5       New Jersey           10
6     Pennsylvania           14
7         Maryland            2
8         Virginia           28
9   North Carolina           17
10  South Carolina           32
11         Georgia           14
12         Florida            1

或者：

pd.concat((West_quakes, East_quakes), keys=('West','East'))

这使：

                  state  Occurrences
West 0       California        18108
     1           Oregon          376
     2       Washington          973
     3           Alaska        12326
East 0            Maine           36
     1    New Hampshire           13
     2    Massachusetts           10
     3      Connecticut            5
     4         New York           35
     5       New Jersey           10
     6     Pennsylvania           14
     7         Maryland            2
     8         Virginia           28
     9   North Carolina           17
     10  South Carolina           32
     11         Georgia           14
     12         Florida            1

或者：

pd.concat((West_quakes, East_quakes), axis=1, keys=('West','East'))

输出：

          West                        East            
         state Occurrences           state Occurrences
0   California     18108.0           Maine          36
1       Oregon       376.0   New Hampshire          13
2   Washington       973.0   Massachusetts          10
3       Alaska     12326.0     Connecticut           5
4          NaN         NaN        New York          35
5          NaN         NaN      New Jersey          10
6          NaN         NaN    Pennsylvania          14
7          NaN         NaN        Maryland           2
8          NaN         NaN        Virginia          28
9          NaN         NaN  North Carolina          17
10         NaN         NaN  South Carolina          32
11         NaN         NaN         Georgia          14
12         NaN         NaN         Florida           1

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