<p>如果只想添加一列,可以使用<a href="http://pandas.pydata.org/pandas-docs/stable/generated/pandas.Series.map.html" rel="nofollow">map()</a>方法:</p>
<pre><code>In [290]: df1['TA2'] = df1.EQ_NR.map(df2.set_index('EQ_NR').TA)
In [291]: df1
Out[291]:
FAK_ART FAK_DAT LEIST_DAT KD_CRM MW_BW EQ_NR MATERIAL KW_WERT NETTO_EURO TA TA2
0 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.150 18.90 SDH AAA
1 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.145 18.27 SDH AAA
2 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.145 18.27 NaN AAA
3 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.150 18.90 SDH AAA
4 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.150 18.90 NaN AAA
5 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.145 18.27 SDH AAA
6 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380363 B60ETS 0.150 18.90 SDH AAA
7 ZPAF 2015-12-10 2015-12-31 T-HOME ICP E 1001380594 B60ETS 3.011 252.92 DSLAM/MSAN NaN
8 ZPAF 2015-12-10 2015-12-31 T-HOME ICP B 1001380594 B60ETS 3.412 429.91 DSLAM/MSAN NaN
</code></pre>
<p>其中df2:</p>
<pre><code>In [288]: df2
Out[288]:
EQ_NR TA
0 1001380363 AAA
</code></pre>
<p>注意:<code>df2.EQ_NR</code>必须是唯一的,否则会得到<code>InvalidIndexError: Reindexing only valid with uniquely valued Index objects</code>异常。<code>df1.EQ_NR</code>可能有重复项。。。你知道吗</p>