擅长:python、mysql、java
<p>我觉得这应该行得通。在</p>
<pre><code>Prod_part = volumes.where(volumes.Date <= volumes.BeforeDate)\
.where(volumes.Before == "Prod")[["Water", "Oil"]].sum(
axis=1, min_count=1)
Inj_part = volumes.where(volumes.Date <= volumes.BeforeDate).where(volumes.Before == "Inj")["Inject"]
volumes["totals_before"] = Inj_part.combine_first(Prod_part)
volumes.totals_before.ffill(inplace=True)
0 20.0
1 30.0
2 30.0
3 700.0
4 720.0
5 720.0
6 1000.0
7 1500.0
8 1500.0
</code></pre>
<p>同样,使用<code>to_dict</code>函数给你的数据帧来拯救我们的生命。在</p>