python dataframe如何填充以减少行数

Use DataFrame.reindex in list comprehension:

dfs = [df1, df2, df3]
dfs = [x.reindex(range(10), fill_value=0) for x in dfs]

如果需要通过最大索引值重新索引，则动态创建最大长度：

m = len(max(dfs, key=len))
dfs = [x.reindex(range(m), fill_value=0) for x in dfs]