Pandas 数据框合并但创建 NaN 值

Question

I have two pandas dataframes with one column in each which looks like:

df1                        df2
Price                     volume
 20                        200
 12                        50
 43                        10
 45                        5

When I try to merge the two dataframes using: new_df = pd.concat([Volume, Price], axis=1) i get

    Volume      Price
3   20           NaN
4   NaN          200
5   12           NaN
6   NaN          50
7   43           NaN

I've tried using pd.concat / pd.merege / pd.join but can't seem to get a clean merge. whats the best way to go about fixing this?

Answer 1

df1 = pd.DataFrame({'Price': [20, 12, 43, 45]})
df2 = pd.DataFrame({'volume': [200, 50, 10, 5]})

new_df = pd.concat([df1, df2], axis=1)

It works for me and I do not get any NaN values. Use dataframe names in pd.concat, not column names.