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- Python list vs. array – when to use? - Stack Overflow
The list is the part of python's syntax so it doesn't need to be declared whereas you have to declare the array before using it You can store values of different data-types in a list (heterogeneous), whereas in Array you can only store values of only the same data-type (homogeneous)
- c++ - vector vs. list in STL - Stack Overflow
List is Doubly Linked List so it is easy to insert and delete an element We have to just change the few pointers, whereas in vector if we want to insert an element in the middle then each element after it has to shift by one index Also if the size of the vector is full then it has to first increase its size So it is an expensive operation
- Array versus List lt;T gt;: When to use which? - Stack Overflow
Using e g List<Point> list, it would be necessary to instead say Point temp=list[3]; temp x+=q; list[3]=temp; It would be helpful if List<T> had a method Update<TP>(int index, ActionByRefRef<T,TP> proc, ref TP params) and compilers could turn list[3] x+=q; into {list Update(3, (ref int value, ref int param)=>value+=param, ref q); but no
- python - Access item in a list of lists - Stack Overflow
You can access the elements in a list-of-lists by first specifying which list you're interested in and then specifying which element of that list you want For example, 17 is element 2 in list 0, which is list1[0][2]: >>> list1 = [[10,13,17],[3,5,1],[13,11,12]] >>> list1[0][2] 17 So, your example would be 50 - list1[0][0] + list1[0][1] - list1
- Identify duplicate values in a list in Python - Stack Overflow
list count() is a O(N) job (all elements in the list are compared to count) and you are doing this in a loop over N elements, giving you quadratic performance, O(N^2) So for a 10-element list 100 steps are executed, for a 1000 element list 1 million, etc –
- python - What does list [x::y] do? - Stack Overflow
If you skip the end index, like in your question, it would take elements from the start index (x), pick every yth element until it reaches the end of the list if y is positive and beginning of the list if y is negative E g l[1::-1] = [2,1] l[1::2] = [2,4,6] The default step size is 1
- Lambda function in list comprehensions - Stack Overflow
This question touches a very stinking part of the "famous" and "obvious" Python syntax - what takes precedence, the lambda, or the for of list comprehension I don't think the purpose of the OP was to generate a list of squares from 0 to 9 If that was the case, we could give even more solutions: squares = [] for x in range(10): squares append(x*x)
- writing a list to a txt file in python - Stack Overflow
writelines() needs a list of strings with line separators appended to them but your code is only giving it a list of integers To make it work you'd need to use something like this: To make it work you'd need to use something like this:
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