set

问题 In Scala, both concurrent and non-concurrent Sets have exactly the same type: // A regular Set in Scala, not concurrent. val regularSet: mutable.Set[Int] = mutable.Set[Int]() // A concurrent set. It has the same type as a regular set, but underneath, it is actually concurrent. In my opinion, this is a flaw in the type system for Scala collections val concurrentSet: mutable.Set[Int] = java.util.concurrent.ConcurrentHashMap.newKeySet[Int]().asScala I'd like a way to actually test whether a set

问题 If there is the following code in a class, are get and set methods associated to the variable? How can I access get and set with an instance of the class? public string Something { get; set; } 回答1: This syntax comes with .Net Framework 3.5 (automatic-property) It's like : private string something; public string Something { get { return something; } set { something = value; } } To access to this variable (supposed to be in a MyClass class) : // GET MyClass myObj = new MyClass(); string test =

问题 I've a pandas series whose elements constitute frozensets: data = {0: frozenset({'apple', 'banana'}), 1: frozenset({'apple', 'orange'}), 2: frozenset({'banana'}), 3: frozenset({'kumquat', 'orange'}), 4: frozenset({'orange'}), 5: frozenset({'orange', 'pear'}), 6: frozenset({'orange', 'pear'}), 7: frozenset({'apple', 'banana', 'pear'}), 8: frozenset({'banana', 'persimmon'}), 9: frozenset({'apple'}), 10: frozenset({'banana'}), 11: frozenset({'apple'})} tokens = pd.Series(data); tokens 0 (apple,

问题 I've the variable varCurrentYear varCurrentYear = Year(Today()) And I wrote this set analysis expression The result it’s not correct. By the way If the variable is declared in this way varCurrentYear = 2014 The result is correct. Why? Thank's 回答1: I'd use Sum({$<Year={'$(varCurrentYear)'}>}Orders) resp without quotes if varCurrentYear is numeric Sum({$<Year={$(varCurrentYear)}>}Orders) See http://tools.qlikblog.at/SetAnalysisWizard/?sa=MCKA Regards Stefan 回答2: I know it looks strange, but you

问题 I try to load the following yaml sequence : - Person(paul): firstName: Paul lastName: Lumbergh children : - Person(bill) - Person(jane) which i tried to load in the following bean : public class Person { private long id; private String firstName; private String lastName; private Person father; private Set<Person> children; } I got this error which is due to the fact that snakeYaml load my sequence in a java.util.List instead of java.util.Set. Is it a way to force snakeYAML to load a sequence

问题 I'm trying to write a program in R that when, given a vector, will return all possible tuples of elements from that vector. For example: tuples(c('a','b','c')) = c('a','b','c'); c('a','b'); c('a','c'), c('b','c'); c('a'); c('b'); c('c') I think it should return a list of vectors. For reference, here is a program that does a similar function in Stata. 回答1: You can use combn : x <- 1:3 unlist(lapply(x, function(n) combn(x, n, simplify=FALSE)), recursive=FALSE) 来源： https://stackoverflow.com

问题 I am trying to figure out a way in R to take the difference of two string vectors, but only based on the first 3 columns that are tab delimited in each string. For Example this is list1 and list2 list1: "1\t1113200\t1118399\t1\t1101465\t1120176\tENSRNOG00000040300\tRaet1l\t0\n" "1\t1180200\t1187599\t1\t1177682\t1221416\tENSRNOG00000061316\tAABR07000121.1\t0\n" "1\t1180200\t1187599\t1\t1177632\t1221416\tENSRNOG00000061316\tAABR07000121.1\t0\n" list2: "1\t1113200\t1118399\t1\t1101465\t1120176

问题 I am using multiprocessing in Python 2.7 to process a very large set of data. As each process runs, it adds integers to a shared mp.Manager.Queue(), but only if some other process hasn't already added the same integer. Since you can't do an "in"-style membership test for Queues, the way I'm doing it is to check each int for membership in a shared mp.Manager.list(). The list will eventually have ~30 million entries, and so membership tests will be extremely slow, nullifying the advantage of

问题 My app uses mutable sets of custom elements. Once I had a crash with error „Duplicate element found in Set. Elements may have been mutated after insertion.“ Searching for an explanation, I found this post, which I don’t fully understand. My impression is that one should not modify an element of a set, since this would modify also the hash value of the set, so that further accesses might fail. My questions: Is it allowed to modify an element of a mutable set, or which modification are allowed,

问题 This question already has answers here : Bidirectional multi-valued map in Java (6 answers) Closed 6 years ago . Is there an implementation of the following data-structure already implemented in Java: Say I want the set for '2' ('A', 'C', 'D') but I also want the set for 'A' ('1', '2') 回答1: You have no such data structure in the Java Collections Framework. I suggest you the guava library you may find something useful there. Note that what you have here is essentially a undirected graph so