Append 基于键值的列表列表

Question

I'm converting 2 Dataframes (I will have more dfs) in 2 lists, to group them by a key column "CNPF_UF_MES".

So I'll have list of lists, each list based on a key value.

But I'm having trouble to append the final result.

import pandas as pd

df1 = pd.DataFrame({
    'CNPJ_UF_MES': ['1-MG', '1-MG', '2-MG'],
    'CLIENTE_PAR_COMEX': ['1_2_3', '2_3_4', '3_4_5'],
    'REG': ['1110', '1110', '1110'],
    'COD_IP_PAR': ['200', '200', '200'],
    'COD_CLIENTE': ['xxr', 'xxv', 'xxw'],
    'IND_COMEX': ['wer', 'cad', 'sder'],
    'IND_EXTEMP': ['key_1', 'key_2', 'key_3'],
    'DT_INI': ['01032021', '01032021', '01032021'],
    'DT_FIN': ['31032021', '31032021', '31032021'],
    'VALOR': ['wer', 'cad', 'sder'],
    'PIPE_FIN': ['', '', '']
})


df2 = pd.DataFrame({
    'CNPJ_UF_MES': ['1-MG', '1-MG', '1-MG', '1-MG', '2-MG', '2-MG'],
    'CLIENTE_PAR_COMEX': ['1_2_3', '2_3_4', '3_4_5','1_2_3', '2_3_4', '3_4_5'],
    'REG': ['1110', '1110', '1110', '1110', '1110', '1110'],
    'COD_MCAPT': ['C-200', 'C-200', 'C-200', 'C-200', 'C-200', 'C-200'],
    'DT_OP': ['07032021', '07032021', '07032021', '08032021', '08032021', '08032021'],
    'VALOR': ['1', '2', '3', '1', '2', '3'],
    'QTD': ['2', '2', '2', '2', '2', '2'],
    'CNPJ_ADQUI': ['123', '123', '123', '123', '123', '123'],
    'PIPE_FIN': ['', '', '', '', '', '']

})



list1 = df1.values.tolist()
#print(list1)

values = set(map(lambda x:x[0], list1))
newlist1 = [[y for y in list1 if y[0]==x] for x in values]

print(newlist1)

list2 = df2.values.tolist()
#print(list2)


values = set(map(lambda x:x[0], list2))
newlist2 = [[y for y in list2 if y[0]==x] for x in values]

print(newlist2)

##here is my problem:
list3 = newlist1.append(newlist2)
print(list3)

I wish to have lists of lists appended by this key column.

Any ideas?

This is expected output:

[[
  ['2-MG', '3_4_5', '1110', '200', 'xxw', 'sder', 'key_3', '01032021', '31032021', 'sder', ''],
  ['2-MG', '2_3_4', '1110', 'C-200', '08032021', '2', '2', '123', ''],
  ['2-MG', '2_3_4', '1110', 'C-200', '08032021', '2', '2', '123', '']
  ],
 [
  ['1-MG', '1_2_3', '1110', '200', 'xxr', 'wer', 'key_1', '01032021', '31032021', 'wer', ''],
  ['1-MG', '2_3_4', '1110', '200', 'xxv', 'cad', 'key_2', '01032021', '31032021', 'cad', ''],
  ['1-MG', '1_2_3', '1110', 'C-200', '07032021', '1', '2', '123', ''],
  ['1-MG', '2_3_4', '1110', 'C-200', '07032021', '2', '2', '123', ''],
  ['1-MG', '3_4_5', '1110', 'C-200', '07032021', '3', '2', '123', ''],
  ['1-MG', '1_2_3', '1110', 'C-200', '08032021', '1', '2', '123', '']
  ]]

I'll manipulate this lists later and write them in csv, each CSV file would be grouped by "CNPF_UF_MES".

Regards,

Tanai

Answer 1

The situation where append returns 'None' value was discussed here .

You can improve your code in this way:

list3 = newlist1 + newlist2