Separate List data with Python

Question

I have a list of multiple strings ) and I want to separate them by :

MainList :

[
    GENERAL NOTES & MISCELLANEOUS DETAILS_None_None_None, 
    STR_XX_XX_0001, 
    STR_XX_XX_0002, 
    STR_XX_XX_0003, 
    GENERAL ARRANGEMENT_None_None_None, 
    STR_XX_XX_10001.0, 
    STR_XX_XX_10002.0, 
    STR_XX_XX_10003.0, 
    STR_XX_XX_10004.0, 
    STR_XX_XX_10005.0, 
    STR_XX_XX_10006.0

]

if string "_None_None_None" found in main list, it can add this data in new empty list and and remaining STR_XX_XX_0001 value to another list and it goes until it found another string with "_None_None_None" and do the same.

I have tried myself, But I think I won't be able to break my loop when it will find next string with "_None_None_None". Just figuring out the way, not sure logic is right.

    empty1 = []
    empty2 = []

    for i in MainList:
            if "_None_None_None" in i:
               empty1.append(i)
            # Need help on hear onwards
            else:
                while "_None" not in i:
                    empty2.append(i)
                break

I am expecting the Output result in two list. Something like this:

List1:

[
    GENERAL NOTES & MISCELLANEOUS DETAILS_None_None_None, 
    GENERAL ARRANGEMENT_None_None_None
]

List2:

[
[STR_XX_XX_0001,STR_XX_XX_0002,STR_XX_XX_0003],[STR_XX_XX_10001.0,STR_XX_XX_10002.0,STR_XX_XX_10003.0,STR_XX_XX_10004.0,STR_XX_XX_10005.0,STR_XX_XX_10006.0]
]

List2 is the list with sublists

user_3874623 · Answer

You are making it a little too complicated, you can let the list run the whole way through without the internal while loop. Just make the decision for each element as it shows up in the loop:

empty1 = []
empty2 = []

for i in MainList:
    if "_None_None_None" in i:
        empty1.append(i)
    else:
        empty2.append(i)

This will give you two lists:

> empty1
> ['GENERAL NOTES & MISCELLANEOUS DETAILS_None_None_None',
 'GENERAL ARRANGEMENT_None_None_None']

> empty2
> ['STR_XX_XX_0001',
 'STR_XX_XX_0002',
 'STR_XX_XX_0003',
 'STR_XX_XX_10001.0',
 'STR_XX_XX_10002.0',
 'STR_XX_XX_10003.0',
 'STR_XX_XX_10004.0',
 'STR_XX_XX_10005.0',
 'STR_XX_XX_10006.0']

EDIT Based on comment

If the commenter is correct and you want to group the non-NONE values into separate lists, this is a good use case for itertools.groupby. It will make the groups for you in a convenient, efficient way and your loop will look almost the same:

from itertools import groupby

empty1 = []
empty2 = []

for k, i in groupby(MainList, key = lambda x: "_None_None_None" in x):
    if k:
        empty1.extend(i)
    else:
        empty2.append(list(i))

This will give you the same empty1 but empty2 will not be a list of lists:

[['STR_XX_XX_0001', 'STR_XX_XX_0002', 'STR_XX_XX_0003'],
 ['STR_XX_XX_10001.0',
  'STR_XX_XX_10002.0',
  'STR_XX_XX_10003.0',
  'STR_XX_XX_10004.0',
  'STR_XX_XX_10005.0',
  'STR_XX_XX_10006.0']]

user_5742662 · Answer

You can try the following code snippet:

dlist = ["GENERAL NOTES & MISCELLANEOUS DETAILS_None_None_None","STR_XX_XX_0001","STR_XX_XX_0002","STR_XX_XX_0003", "GENERAL ARRANGEMENT_None_None_None","STR_XX_XX_10001.0","STR_XX_XX_10002.0", "STR_XX_XX_10003.0", "STR_XX_XX_10004.0", "STR_XX_XX_10005.0", "STR_XX_XX_10006.0"]

with_None = [elem for elem in dlist if elem.endswith("_None")]
without_None = [elem for elem in dlist if not elem.endswith("_None")]

You can also write a generic function for the process:

def cust_sept(src_list, value_to_find,f):
    with_value, without_value = [elem for elem in dlist if f(elem,value_to_find)],[elem for elem in dlist if not f(elem,value_to_find)]
    return with_value,without_value

list_one,list_two = cust_sept(dlist,"_None",str.endswith)

Separate List data with Python

2 Answers