Question

我是Python的新手，我正在尝试解决两组不同的数据问题。我已经使用pandas.read_csv

创建了两个数据框s和c

S

  Spread   per1   per2   per3          acc
0  4.50%  1.26%  0.35%  0.50%        0.60%
1  4.45%  1.29%  0.35%  0.50%        0.60%
2  4.40%  1.31%  0.35%  0.50%        0.60%
3  4.35%  1.34%  0.35%  0.50%        0.60%
4  4.30%  1.37%  0.35%  0.50%        0.60%

c

     Cer     OO
0  1.00%  0.65%
1  1.05%  0.68%
2  1.10%  0.71%
3  1.15%  0.73%
4  1.20%  0.76%

所以我想做的是，对于c中Cer和OO的每种组合，我想填充s中的所有记录。（不确定这是否是解释它的好方法）。请参见下面的示例

    Spread  per1    per2    per3    acc     Cer     OO
0   4.50%   1.26%   0.35%   0.50%   0.60%   1.00%   0.65%
1   4.45%   1.29%   0.35%   0.50%   0.60%   1.00%   0.65%
2   4.40%   1.31%   0.35%   0.50%   0.60%   1.00%   0.65%
3   4.35%   1.34%   0.35%   0.50%   0.60%   1.00%   0.65%
4   4.30%   1.37%   0.35%   0.50%   0.60%   1.00%   0.65%
5   4.50%   1.26%   0.35%   0.50%   0.60%   1.05%   0.68%
6   4.45%   1.29%   0.35%   0.50%   0.60%   1.05%   0.68%
7   4.40%   1.31%   0.35%   0.50%   0.60%   1.05%   0.68%
8   4.35%   1.34%   0.35%   0.50%   0.60%   1.05%   0.68%
9   4.30%   1.37%   0.35%   0.50%   0.60%   1.05%   0.68%

我读到熊猫和/或itertools可以帮助我进行这种分析？困惑是在尝试为数据帧 c 中两个字段的每个组合从 s 创建所有记录时。

同样，任何有关文档和/或见解的帮助都将非常有用。谢谢

Answer 1

使用带有merge和临时键的笛卡尔联接：

S.assign(key=1).merge(c.assign(key=1), on='key').drop('key', axis=1)

输出：

   Spread   per1   per2   per3    acc    Cer     OO
0   4.50%  1.26%  0.35%  0.50%  0.60%  1.00%  0.65%
1   4.50%  1.26%  0.35%  0.50%  0.60%  1.05%  0.68%
2   4.50%  1.26%  0.35%  0.50%  0.60%  1.10%  0.71%
3   4.50%  1.26%  0.35%  0.50%  0.60%  1.15%  0.73%
4   4.50%  1.26%  0.35%  0.50%  0.60%  1.20%  0.76%
5   4.45%  1.29%  0.35%  0.50%  0.60%  1.00%  0.65%
6   4.45%  1.29%  0.35%  0.50%  0.60%  1.05%  0.68%
7   4.45%  1.29%  0.35%  0.50%  0.60%  1.10%  0.71%
8   4.45%  1.29%  0.35%  0.50%  0.60%  1.15%  0.73%
9   4.45%  1.29%  0.35%  0.50%  0.60%  1.20%  0.76%
10  4.40%  1.31%  0.35%  0.50%  0.60%  1.00%  0.65%
11  4.40%  1.31%  0.35%  0.50%  0.60%  1.05%  0.68%
12  4.40%  1.31%  0.35%  0.50%  0.60%  1.10%  0.71%
13  4.40%  1.31%  0.35%  0.50%  0.60%  1.15%  0.73%
14  4.40%  1.31%  0.35%  0.50%  0.60%  1.20%  0.76%
15  4.35%  1.34%  0.35%  0.50%  0.60%  1.00%  0.65%
16  4.35%  1.34%  0.35%  0.50%  0.60%  1.05%  0.68%
17  4.35%  1.34%  0.35%  0.50%  0.60%  1.10%  0.71%
18  4.35%  1.34%  0.35%  0.50%  0.60%  1.15%  0.73%
19  4.35%  1.34%  0.35%  0.50%  0.60%  1.20%  0.76%
20  4.30%  1.37%  0.35%  0.50%  0.60%  1.00%  0.65%
21  4.30%  1.37%  0.35%  0.50%  0.60%  1.05%  0.68%
22  4.30%  1.37%  0.35%  0.50%  0.60%  1.10%  0.71%
23  4.30%  1.37%  0.35%  0.50%  0.60%  1.15%  0.73%
24  4.30%  1.37%  0.35%  0.50%  0.60%  1.20%  0.76%

使用Python的组合方法

1 个答案: