i'm a beginner on Python and what i'm trying to do is adding an element in a specific index in a list of values associated to my key in Python 3, using defaultdict.
My default_dict structure is the following:
default_dict = ['label_1':[list of doubles], 'label_2':[list of doubles], etc..]
suppose i have a double d = 6.5 and i want to insert it as a value of the list with key: label_1 in a specific index.
if my list is:[12.3, 11.8, 8.6, 5.8, 3.1]
i would like to insert my d = 6.5 between 8.6 and 5.8
i know a call like default_dict[label_1].append(d) would result in a list like that:
[12.3, 11.8, 8.6, 5.8, 3.1, 6.5]
is there a function i can use like:
default_dict[label_1].add(d, index_to_insert) ?
i thought i could fetch the entire list, modify it by myself and switch the new one with the old i had but i think this is a onerous call (i need to call that a lot of time) and i need a more efficient way!
Thanks in advance!
Use list.insert(index,object) for adding into specific index of List.
Please note you have to do this for inside list you have in default_dict as you are referring.
ex:
>>li1 = [1,2,3,4,5]
>>li1.insert(5,8)
>>li1
[1, 2, 3, 4, 5, 8]
>>li1.insert(1,99)
>>li1
[1, 99, 2, 3, 4, 5, 8]
More efficient way is slicing too, if you are inserting single or multiple elements at specific index without replacing existing values.
>>li1 = [1,2,3,9,6,4,9,0]
>>li1[3:3] = [7]
>>li1
[1, 2, 3, 7, 9, 6, 4, 9, 0]
Please note time complexity for insert is O(n) and slicing is O(k)