擅长:python、mysql、java
<p>我想帕金森病可能是一种实现目标的方法。在</p>
<pre><code>In [47]: import pandas as pd
In [48]: data = {
...: 'a': [1, 2, 3],
...: 'b': [5, 6, 7],
...: 'c': [8, 9, 10]
...: }
In [49]: x = pd.DataFrame(data)
In [50]: x
Out[50]:
a b c
0 1 5 8
1 2 6 9
2 3 7 10
In [51]: l = ["a", "b"]
In [52]: x[l]
Out[52]:
a b
0 1 5
1 2 6
2 3 7
In [53]: l = ["a", "b", "c", "d"]
In [55]: y = pd.DataFrame(columns=l)
In [56]: y
Out[56]:
Empty DataFrame
Columns: [a, b, c, d]
Index: []
In [57]: pd.concat((x, y))
Out[57]:
a b c d
0 1.0 5.0 8.0 NaN
1 2.0 6.0 9.0 NaN
2 3.0 7.0 10.0 NaN
In [58]: pd.concat((x, y)).fillna(0)
Out[58]:
a b c d
0 1.0 5.0 8.0 0
1 2.0 6.0 9.0 0
2 3.0 7.0 10.0 0
</code></pre>