如何组合两列（Python）中具有相同值的行？

Question

我目前有一个 csv 文件，如下所示。第一部分只显示列名称。

"f","p","g"
"foo","in","void"
"foo","out","void"
"foo","length","void"
...

每个 f 值的 g 列值都相同。唯一独特的部分是 p。 使用 python，我如何将其组合如下：

"foo","in","out","length","void"

需要注意的一点是 csv 文件要大得多，并且某些 f 值可能具有更多 p 值。例如，它可能是这样的：

"goo","a","int"
"goo","b","int"
"goo","c","int"
"goo","d","int"
"goo","e","int"
"goo","f","int"
...

Answer 1

我希望我已经正确理解了您的问题。您可以按“f”、“g”列分组，然后聚合行：

x = df.groupby(["f", "g"], as_index=False)["p"].agg(list)
for vals in x.apply(lambda x: [x["f"], *x["p"], x["g"]], axis=1):
    print(vals)

打印：

['foo', 'in', 'out', 'length', 'void']
['goo', 'a', 'b', 'c', 'd', 'e', 'f', 'int']