擅长:python、mysql、java
<p>那么下面的方法呢:</p>
<pre><code>In [160]: df
Out[160]:
field1 field2 2014 2015 2016 2017
0 a 0.0 1.0 2.0 3.0 -10.0
1 b 5.0 6.0 7.0 NaN NaN
2 c 10.0 11.0 12.0 NaN NaN
3 d 15.0 16.0 17.0 NaN NaN
4 e 20.0 21.0 NaN NaN NaN
5 f 25.0 26.0 27.0 28.0 29.0
6 g 30.0 31.0 32.0 33.0 34.0
In [180]: df.groupby(lambda x: 'obs' if x.isdigit() else x, axis=1) \
...: .last() \
...: .assign(date=df.filter(regex='^\d{4}').loc[:, ::-1].notnull().idxmax(1))
Out[180]:
field1 field2 obs date
0 a 0.0 -10.0 2017
1 b 5.0 7.0 2015
2 c 10.0 12.0 2015
3 d 15.0 17.0 2015
4 e 20.0 21.0 2014
5 f 25.0 29.0 2017
6 g 30.0 34.0 2017
</code></pre>