set

问题 I have a relative straightforward thing I want to do: Given a query number Q, a query distance d, and a set of numbers S, determine whether or not S contains any numbers with Hamming distance less than or equal to d. The simplest solution is to just make S a list and iterate over it, computing distances. If a distance less than or equal d is computed, bail out an return TRUE. But considering that all I want to do is check for an existence, something faster than a linear time solution should

问题 The Issue I have tried several approaches, but haven't been able to find out how to add numbers to a NS set. This is all running inside a lambda function. What I'm trying to accomplish I am creating a dynamodb table where different colors in hex align to a set of ids. I am optimizing the table for fast reads and to avoid duplicates which is why I would like to maintain a set of ids for each hex. How I'm adding items to the table: let doc = require('dynamodb-doc'); let dynamo = new doc

问题 Which one of these is faster? Is one "better"? Basically I'll have two sets and I want to eventually get one match from between the two lists. So really I suppose the for loop is more like: for object in set: if object in other_set: return object Like I said - I only need one match, but I'm not sure how intersection() is handled, so I don't know if its any better. Also, if it helps, the other_set is a list near 100,000 components and the set is maybe a few hundred, max few thousand. 回答1: from

问题 I have a dataset of ca. 9K lists of variable length (1 to 100K elements). I need to calculate the length of the intersection of all possible 2-list combinations in this dataset. Note that elements in each list are unique so they can be stored as sets in python. What is the most efficient way to perform this in python? Edit I forgot to specify that I need to have the ability to match the intersection values to the corresponding pair of lists. Thanks everybody for the prompt response and

问题 I have two maps: Map<String, Object> map1; Map<String, Object> map2; I need to receive difference between these maps. Does exist may be apache utils how to receive this difference? For now seems need take entry set of each map and found diff1 = set1 - set2 and diff2 = set2- set1. After create summary map =diff1 + diff2 It looks very awkwardly. Does exist another way? Thanks. 回答1: How about google guava?: Maps.difference(map1,map2) 回答2: Here is a simple snippet you can use instead of massive

问题 Python 2 Sets are collections of unordered values. If I construct a set via a set literal, e.g. s = {'a', 'b', 'c'} and then print it, I get the elements in some scrambled order. However, it seems that in Python 2.7, the above example always results in the same ordering: print(s) # set(['a', 'c', 'b']) in Python 2.7 How does Python 2.7 decide on this ordering? Even the hashes of 'a' , 'b' and 'c' are not in the order produced. Python 3 In Python 3.x (including 3.6 where dict keys are ordered)

问题 I have some sets I would like to take the Cartesian product of, which is working well. However, I want to remove all elements of this new set which are identical under a permutation of the elements. For example, take the following code: import itertools as ittools x = 2 y = 3 z = 5 flist = list(ittools.product([x,y,z],repeat=3)) for f in flist: print reduce(lambda a,b: a*b, f) This code find the Cartesian product of the set {2,3,5} and returns the product of all three components of each

问题 I'm writing this code and I'm getting this error: [Error] passing 'const std::vector' as 'this' argument of 'void std::vector<_Tp, _Alloc>::push_back(const value_type&) [with _Tp = metastock7, _Alloc = std::allocator, std::vector<_Tp, _Alloc>::value_type = metastock7]' discards qualifiers [-fpermissive] struct A{ string name; vector<B> rows; }; set<A, classcomp> set; vector<B> data; //I filled the vector in my code std::set<A, classcomp>::iterator it; std::pair<std::set<A, classcomp>:

问题 I've been learning Python for about over a month, and I ran into a discussion about views and sets. The book I'm using, Learning Python, says that views are iterables and have their objects in the same order that the dictionary does, but views also supports set operations. It seems to me that they can do everything sets do. It looks like a duck, quacks like a duck, and allow set operations like a duck. Why are sets and views then separate types of objects? Also, I searched 'Set View Python

问题 I am using this script from The little schemer, to get intersection of two sets. But I am getting unbound identifier error at 'member?', can anyone please tell what's wrong with it: (define intersect (lambda (set1 set2) (cond ((null? set1) (quote ())) ((member? (car set1) set2) (cons (car setl) (intersect (cdr set1) set2))) (else (intersect (cdr setl) set2))))) I was missing this function above: (define member? (lambda (a lat) (cond ((null? lat) #f) (else (or (eq? (car lat) a) (member? a (cdr