The first, [:], is creating a slice (normally often used for getting just part of a list), which happens to contain the entire list, and thus is effectively a copy of the list. The second, list(), is using the …

I have a piece of code here that is supposed to return the least common element in a list of elements, ordered by commonality: def getSingle(arr): from collections import Counter c = …

The first way works for a list or a string; the second way only works for a list, because slice assignment isn't allowed for strings. Other than that I think the only difference is speed: it looks …

2009年1月12日 · A List uses an internal array to handle its data, and automatically resizes the array when adding more elements to the List than its current capacity, which makes it more …

2016年11月29日 · (List<Customer>)(Object)list; you must be sure that at runtime the list contains nothing but Customer objects. Critics say that such casting indicates something wrong with …

2017年10月5日 · @Sandy Chapman: List.of does return some ImmutableList type, its actual name is just a non-public implementation detail. If it was public and someone cast it to List again, …

Learn how to properly create nested HTML lists with examples and best practices, as discussed on Stack Overflow.

Don't use quotes on the command line 1 Don't use type=list, as it will return a list of lists This happens because under the hood argparse uses the value of type to coerce each individual …

Given a dataframe, I want to groupby the first column and get second column as lists in rows, so that a dataframe like: a b A 1 A 2 B 5 B 5 B 4 C 6 becomes A [1,2] B [5,5,4] C [6] How do I do this?

2015年2月25日 · A list of lists would essentially represent a tree structure, where each branch would constitute the same type as its parent, and its leaf nodes would represent values.