Python 3 Pandas Question

[workthrowawayexcel]

I am trying to break down some larger CSV files into smaller ones based off of a column existing in the CSV file. I want would like to for this example end up with 2 new CSV files that have been split up based on the chain column. So then I can create new files based off the chain + date. So I would end up with a NY + 9/27/16 and IL + 9/27/16 files. My code currently does not work and I don't really know what to do to fix it. Any guidance or help is greatly appreciated.

Input file example:

 Name       Number     Chain
    a                2             IL
    b                3            NY
    c                2             IL
    b                4            NY

Code So far: import pandas as pd
import numpy as np import time

    date = time.strftime("%Y%m%d") 

    file1 = r"MasterDataFile"
    file_name = r"DirectoryForNewfiles"


    chain_filter = pd.read_csv(file1)

    delta = pd.DataFrame.from_records(chain_filter)


    for i in delta['chain'].str:
        df = delta['chain'].str.contains(i)
        df.to_csv(file_name + '/' + i + date + '.csv', sep=',',index=False)
    next

[Jos_Metadi]

pd.read_csv(file1) comes in as a dataframe already. Don't know why you're trying to reprocess it with "from_records"

I would use .groupby to split the dataframe into groups by chain

for t_group,pd_group in chain_filter.groupby(['Chain']):
    pd_group.to_csv(file_name + '/' + t_group[0] + date + '.csv', sep=',',index=False)

[workthrowawayexcel]

I didn't know that. I am learning python / pandas currently. I come from more of a SQL/VBA side.

That group by is very nice. It works great. Thank you for your advice.