Assume I have 3 dataframes as follows:
2011:
| Bridge_No | Location | Area | 2011 |
|---|---|---|---|
| 1 | NY | 10 | 3 |
| 2 | FL | 20 | 4 |
| 3 | NJ | 15 | 6 |
2012:
| Bridge_No | Location | Area | 2012 |
|---|---|---|---|
| 2 | FL | 20 | 5 |
| 3 | NJ | 15 | 3 |
| 4 | CN | 45 | 9 |
2013:
| Bridge_No | Location | Area | 2013 |
|---|---|---|---|
| 2 | FL | 20 | 8 |
| 6 | MI | 30 | 8 |
| 4 | CN | 45 | 9 |
I need a final merged dataset as follows:
| Bridge_No | Location | Area | 2011 | 2012 | 2013 |
|---|---|---|---|---|---|
| 1 | NY | 10 | 3 | Nan | Nan |
| 2 | FL | 20 | 4 | 5 | 8 |
| 3 | NJ | 15 | 6 | 3 | NaN |
| 4 | CN | 45 | Nan | 9 | 9 |
| 6 | MI | 30 | Nan | NaN | 8 |
CodePudding user response：
We can iterate over each DataFrame and 