Meaning of list[-1] in Python - Stack Overflow
2018年9月19日 · All your return c.most_common()[-1] statement does is call c.most_common and return the last value in the resulting list, which would give you the least common item in that list. Essentially, this line is equivalent to:
How to list all installed packages and their versions in Python?
2018年7月8日 · For Windows 10, I think this is what you are looking for a list of available installed Pythons. This is different from a list of packages as you can see below. Also, on Ubuntu 20.04, I think the command is Python3 -0 list. Yes, this works similar to node version manager. c:\Users\user\AppData\Local\Programs\Python>py -0 list Python 0 not found!
slice - How slicing in Python works - Stack Overflow
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 like it's a little faster the first way. Try it yourself with timeit.timeit() or preferably timeit.repeat().
python - if/else in a list comprehension - Stack Overflow
Since a list comprehension creates a list, it shouldn't be used if creating a list is not the goal; it shouldn't be used simply to write a one-line for-loop; so refrain from writing [print(x) for x in range(5)] for example.
What are the options to clone or copy a list in Python? - Stack …
@loved.by.Jesus: Yeah, they added optimizations for Python level method calls in 3.7 that were extended to C extension method calls in 3.8 by PEP 590 that remove the overhead of creating a bound method each time you call a method, so the cost to call alist.copy() is now a dict lookup on the list type, then a relatively cheap no-arg function call that ultimately invokes the same thing …
Best way to remove elements from a list - Stack Overflow
2014年2月2日 · This makes indexing a list a[i] an operation whose cost is independent of the size of the list or the value of the index. When items are appended or inserted, the array of references is resized. Some algorithm is applied to improve the performance of appending items repeatedly; when the array must be grown, some extra space is allocated so the ...
How to initialize List<String> object in Java? - Stack Overflow
2012年11月15日 · Just in case, any one still lingering around this question. Because, i see one or two new users again asking the same question and everyone telling then , No you can't do that, Dear Prudence, Apart from all the answers given here, I would like to provide additional Information - Yes you can actually do, List list = new List(); But at the cost of writing …
What is the syntax to insert one list into another list in python?
2010年9月20日 · List slicing is quite flexible as it allows to replace a range of entries in a list with a range of ...
Get a list of numbers as input from the user [duplicate]
Get a list of number as input from the user. This can be done by using list in python. L=list(map(int,input(),split())) Here L indicates list, map is used to map input with the position, int specifies the datatype of the user input which is in integer datatype, and split() is used to split the number based on space..
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 ...