How to split a list into sublists that begin with the delimiting character? [closed]

Question

• I would like to split a list into sublists that begin with the delimiting character
  • The delimiting character must be kept
  • The delimiting character must be the first character of each sublist

Example:

delimiter = "x" 
input = ["x","a","x","x",1,2,3,"a","a","x","e"]
output = [["x","a"], ["x"], ["x",1,2,3,"a","a"], ["x","e"]]

• In addition to the solutions below, see Python splitting a list based on a delimiter word
  • The question is similar, but the expected output is slightly different. For instance, the top solution there, returns and empty list at index 0.

Answer 1

Step 1: Find the indices where the variable occurs in your list:

idx = [ix for ix, val in enumerate(input) if val==variable]

Step 2: Generate sub-lists using list slicing:

res = [input[i:j] for i,j in zip(idx, idx[1:]+[len(input)])]

Output

print(res)
# [['x', 'a'], ['x'], ['x', 1, 2, 3, 'a', 'a'], ['x', 'e']]

Answer 2

You can use the below function to get desired output.

Try this :

def splitList(inputList, delim):
    finalList = []
    chunk = []
    for val in inputList:
        if val == delim:
            finalList.append(chunk)
            chunk = [delim]
        else:
            chunk.append(val)
    finalList.append(chunk)        
    return finalList[1:]


my_input_list = ["x","a","x","x",1,2,3,"a","a","x","e"]
my_output = splitList(my_input_list, "x")    #just call the function with input_list and delimiter to split onto.


print(my_output)

>>> [["x","a"],["x"],["x",1,2,3,"a","a"],["x","e"]]