Create two dataframe from a given dataframe

Question

Assume that I have the following dataframe

id  item_name      item_date   item_quantity
0   computer hp    01/10/2018   50
1   computer hp    02/10/2018  201
2   computer dell  01/10/2018  45
3   computer dell  02/10/2018  59

I would like a way to create two dataframe from this one :

new_df1

id  item_name      item_date   item_quantity
0   computer hp    01/10/2018   50
1   computer hp    02/10/2018  201

new_df2

id  item_name      item_date   item_quantity
2   computer dell  01/10/2018  45
3   computer dell  02/10/2018  59

Can you explain me how to do this with a minimum (?) time ? Thank you. If you don't understand, just let me know. I will rephrase it ;)

It_is_Chris · Accepted Answer · 2018-11-03 22:50:21Z

you can groupby and use transform(min) to find the min date in each group then use np.split() to split on the index and create new dataframes on each groups min date

# group df on name and the find the min date of each group
group = df.groupby('item_name')['item_date'].transform('min')

# filter find the matches of min date in the original df
x = df.loc[df['item_date'] == group]

# get the indices
idx = list(x.index.values)

# split the df into dfs
dfs = np.split(df, idx)

dfs[1]

    id  item_name   item_date   item_quantity
0   0   computer hp 1/10/2018   50
1   1   computer hp 2/10/2018   201

dfs[2]

    id  item_name   item_date   item_quantity
2   2   computer dell   1/10/2018   45
3   3   computer dell   2/10/2018   59

2Obe · Accepted Answer · 2018-11-04 09:46:38Z

1

IF you just want to split the dataframe on a given index, use the following:

import pandas as pd 



df = pd.DataFrame({'Date': [1, 2, 3, 4], 'B': [1, 2, 3, 2], 'C': ['A','B','C','D']})

n = 2

df1 = df[:n]
df2 = df[n:]




   Date  B  C
0     1  1  A
1     2  2  B
   Date  B  C
2     3  3  C
3     4  2  D

answered Nov 4, 2018 at 9:46

2Obe

3,7706 gold badges36 silver badges57 bronze badges

Collectives™ on Stack Overflow

Create two dataframe from a given dataframe

new_df1

new_df2

2 Answers 2

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

new_df1

new_df2

2 Answers 2

Comments

Comments

Related