Python has a built-in datatype for an unordered collection of (hashable) things, called a set. If you convert both lists to sets, the comparison will be unordered. set(x) == set(y) Documentation on set EDIT: @mdwhatcott points out that you want to check for duplicates. set ignores these, so you need a similar data structure that … Read more
A list keeps order, dict and set don’t: when you care about order, therefore, you must use list (if your choice of containers is limited to these three, of course 😉 ). dict associates each key with a value, while list and set just contain values: very different use cases, obviously. set requires items to … Read more
Use a list comprehension: [item for item in x if item not in y] If you want to use the – infix syntax, you can just do: class MyList(list): def __init__(self, *args): super(MyList, self).__init__(args) def __sub__(self, other): return self.__class__(*[item for item in self if item not in other]) you can then use it like: x … Read more
List list = new ArrayList(coll); Collections.sort(list); As Erel Segal Halevi says below, if coll is already a list, you can skip step one. But that would depend on the internals of TreeBidiMap. List list; if (coll instanceof List) list = (List)coll; else list = new ArrayList(coll);
You can do this very simply using LINQ. Make sure this using is at the top of your C# file: using System.Linq; Then use the ToList extension method. Example: IEnumerable<int> enumerable = Enumerable.Range(1, 300); List<int> asList = enumerable.ToList();
Python 3: # short circuits at shortest nested list if table is jagged: list(map(list, zip(*l))) # discards no data if jagged and fills short nested lists with None list(map(list, itertools.zip_longest(*l, fillvalue=None))) Python 2: map(list, zip(*l)) [[1, 4, 7], [2, 5, 8], [3, 6, 9]] Explanation: There are two things we need to know to understand … Read more
1) Almost-English style: Test for presence using the in operator, then apply the remove method. if thing in some_list: some_list.remove(thing) The removemethod will remove only the first occurrence of thing, in order to remove all occurrences you can use while instead of if. while thing in some_list: some_list.remove(thing) Simple enough, probably my choice.for small lists … Read more
Just to address the last part of your question, since that really points out the difference between a list and vector in R: Why do these two expressions not return the same result? x = list(1, 2, 3, 4); x2 = list(1:4) A list can contain any other class as each element. So you can … Read more
If you don’t want to modify the list in-place (e.g. for passing the list with an element removed to a function), you can use indexing: negative indices mean “don’t include this element”. x <- list(“a”, “b”, “c”, “d”, “e”); # example list x[-2]; # without 2nd element x[-c(2, 3)]; # without 2nd and 3rd Also, … Read more
Use .rsplit() or .rpartition() instead: s.rsplit(‘,’, 1) s.rpartition(‘,’) str.rsplit() lets you specify how many times to split, while str.rpartition() only splits once but always returns a fixed number of elements (prefix, delimiter & postfix) and is faster for the single split case. Demo: >>> s = “a,b,c,d” >>> s.rsplit(‘,’, 1) [‘a,b,c’, ‘d’] >>> s.rsplit(‘,’, 2) … Read more