python熊猫多列总和

Question

Need some advise: I am trying to SUM the SERIAL COUNT field with the total of SERIAL NUMBERS in a GROUP of the same ITEM NUMBER? Any suggestions welcome?

 fincon_serials = pd.read_csv('Raw Data/LISTSNO Calvinia.TXT',skiprows = 1)

 fincon_codes = pd.read_excel('Raw Data/STKCOUNT Calvinia.xls', index=None)

 fincon_codes = fincon_codes.drop(columns=['GROUP','BIN','Unnamed: 5'])

 fincon_codes = pd.merge(fincon_codes, fincon_serials[['ITEM NUMBER', 'SERIAL NUMBER']], on = ['ITEM NUMBER'])

 fincon_codes['SERIAL COUNT'] = 1

 fincon_codes = fincon_codes.groupby(['ITEM NUMBER','CAT','DESCRIPTION','NORMAL','FAULTY','SUPPLR','SWP-OUT','TOTAL','COST','VALUE','SERIAL NUMBER'])[['SERIAL COUNT']].sum()

 fincon_codes.head()

This is my first question, so please accept my apologies if it is not in the correct format.

I have searched for solution on the PANDAS documentation, but cannot find a solution and suits that which I want to do as the SERIAL COUNT column should count the SERIALS in THE SERIAL NUMBER column and add that to the SERIAL COUNT.

Current output:

What is needed is that the SERIAL COUNT should have a total for each item number group.

Thank you

Answer 1

I have created some data for example:

item_number = pd.Series([1,2,2,1,1,3])
serial_number = pd.Series([112, 111, 111, 134, 155, 111])
another_column = pd.Series([1,2,3,4,5,6])
df = pd.concat([item_number, serial_number, another_column], 1)
df.columns = ['item_number', 'serial_number', 'another_column']

In your data, "another column" is any another column like "CAT", "DESCROPTION", etc. If you need to calculate count of unique values "serial number" in "item number" I think you can just use groupby(['item_number', 'serial_number']) .

result = df.groupby(['item_number', 'serial_number']).another_column.count()

And you will have output like this:

item_number  serial_number
1            112              1
             134              1
             155              1
2            111              2
3            111              1

Do you need concatenate this with other columns? If you can present a peace of your data, then I can write full example.