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, [:], 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 …

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 …

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, …

2010年7月9日 · How can I list all files of a directory in Python and add them to a list?

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?

If your list of lists comes from a nested list comprehension, the problem can be solved more simply/directly by fixing the comprehension; please see How can I get a flat result from a list …

C 7/1/2014 22000 18000 N C 8/1/2014 30000 28960 N C 9/1/2014 53000 51200 N I want to be able to return the contents of column 1 df['cluster'] as a list, so I can run a for-loop over it, and …

2013年4月17日 · In C# if I have a List of type bool. What is the fastest way to determine if the list contains a true value? I don’t need to know how many or where the true value is. I just need to …