擅长:python、mysql、java
<p>基于<a href="https://stackoverflow.com/questions/44706485/how-to-remove-rows-in-a-pandas-dataframe-if-the-same-row-exists-in-another-dataf">this answer</a>中的技术,我们可以去掉任何作为(玩家,前一个团队)组合存在的(玩家,当前团队)组合</p>
<pre><code>>>> df
Player CurrentTeam PreviousTeam
0 James Team A Null
1 David Team B Null
2 George Team C Null
3 James Team B Team A
4 James Team C Team B
>>> old_teams = df[["Player", "PreviousTeam"]].rename(columns={"PreviousTeam": "Team"})
>>> all_teams = df[["Player", "CurrentTeam"]].rename(columns={"CurrentTeam": "Team"})
>>> current_teams = (pd.merge(all_teams, old_teams, indicator=True, how="outer")
.query("_merge == 'left_only'")
.drop("_merge", axis=1)
.reset_index(drop=True))
>>> current_teams
Player Team
0 David Team B
1 George Team C
2 James Team C
</code></pre>