Search Results

Search found 20883 results on 836 pages for 'wont say'.

Page 661/836 | < Previous Page | 657 658 659 660 661 662 663 664 665 666 667 668  | Next Page >

• Are endless loops in bad form?

  - by rlbond

  So I have some C++ code for back-tracking nodes in a BFS algorithm. It looks a little like this: typedef std::map<int> MapType; bool IsValuePresent(const MapType& myMap, int beginVal, int searchVal) { int current_val = beginVal; while (true) { if (current_val == searchVal) return true; MapType::iterator it = myMap.find(current_val); assert(current_val != myMap.end()); if (current_val == it->second) // end of the line return false; current_val = it->second; } } However, the while (true) seems... suspicious to me. I know this code works, and logically I know it should work. However, I can't shake the feeling that there should be some condition in the while, but really the only possible one is to use a bool variable just to say if it's done. Should I stop worrying? Or is this really bad form. EDIT: Thanks to all for noticing that there is a way to get around this. However, I would still like to know if there are other valid cases.

  Read the article

• LINQ(2 SQL) Insert Multiple Tables Question

  - by Refracted Paladin

  I have 3 tables. A primary EmploymentPlan table with PK GUID EmploymentPlanID and 2 FK's GUID PrevocServicesID & GUID JobDevelopmentServicesID. There are of course other fields, almost exclusively varchar(). Then the 2 secondary tables with the corresponding PK to the primary's FK's. I am trying to write the LINQ INSERT Method and am struggling with the creation of the keys. Say I have a method like below. Is that correct? Will that even work? Should I have seperate methods for each? Also, when INSERTING I didn't think I needed to provide the PK for a table. It is auto-generated, no? Thanks, public static void InsertEmploymentPlan(int planID, Guid employmentQuestionnaireID, string user, bool communityJob, bool jobDevelopmentServices, bool prevocServices, bool transitionedPrevocIntegrated, bool empServiceMatchPref) { using (var context = MatrixDataContext.Create()) { var empPrevocID = Guid.NewGuid(); var prevocPlan = new tblEmploymentPrevocService { EmploymentPrevocID = empPrevocID }; context.tblEmploymentPrevocServices.InsertOnSubmit(prevocPlan); var empJobDevID = Guid.NewGuid(); var jobDevPlan = new tblEmploymentJobDevelopmetService() { JobDevelopmentServicesID = empJobDevID }; context.tblEmploymentJobDevelopmetServices.InsertOnSubmit(jobDevPlan); var empPlan = new tblEmploymentQuestionnaire { CommunityJob = communityJob, EmploymentQuestionnaireID = Guid.NewGuid(), InsertDate = DateTime.Now, InsertUser = user, JobDevelopmentServices = jobDevelopmentServices, JobDevelopmentServicesID =empJobDevID, PrevocServices = prevocServices, PrevocServicesID =empPrevocID, TransitionedPrevocToIntegrated =transitionedPrevocIntegrated, EmploymentServiceMatchPref = empServiceMatchPref }; context.tblEmploymentQuestionnaires.InsertOnSubmit(empPlan); context.SubmitChanges(); } } I understand I can use more then 1 InsertOnSubmit, See SO ? HERE, I just don't understand how that would apply to my situation and the PK/FK creation.

  Read the article

• Remove/squash entries in a vertical hash

  - by Forkrul Assail

  I have a grid that represents an X, Y matrix, stored as a hash here. Some points on the X Y matrix may have values (as type string), and some may not. A typical grid could look like this: {[9, 5]=>"Alaina", [10, 3]=>"Courtney", [11, 1]=>"Gladys", [8, 7]=>"Alford", [14, 11]=>"Lesley", [17, 2]=>"Lawson", [0, 5]=>"Katrine", [2, 1]=>"Tyra", [3, 3]=>"Fredy", [1, 7]=>"Magnus", [6, 9]=>"Nels", [7, 11]=>"Kylie", [11, 0]=>"Kellen", [10, 2]=>"Johan", [14, 10]=>"Justice", [0, 4]=>"Barton", [2, 0]=>"Charley", [3, 2]=>"Magnolia", [1, 6]=>"Maximo", [7, 10]=>"Olga", [19, 5]=>"Isadore", [16, 3]=>"Delfina", [17, 1]=>"Noe", [20, 11]=>"Francis", [10, 5]=>"Creola", [9, 3]=>"Bulah", [8, 1]=>"Lempi", [11, 7]=>"Raquel", [13, 11]=>"Jace", [1, 5]=>"Garth", [3, 1]=>"Ernest", [2, 3]=>"Malcolm", [0, 7]=>"Alejandrin", [7, 9]=>"Marina", [6, 11]=>"Otilia", [16, 2]=>"Hailey", [20, 10]=>"Brandt", [8, 0]=>"Madeline", [9, 2]=>"Leanne", [13, 10]=>"Jenifer", [1, 4]=>"Humberto", [3, 0]=>"Nicholaus", [2, 2]=>"Nadia", [0, 6]=>"Abigail", [6, 10]=>"Zola", [20, 5]=>"Clementina", [23, 3]=>"Alvah", [19, 11]=>"Wallace", [11, 5]=>"Tracey", [8, 3]=>"Hulda", [9, 1]=>"Jedidiah", [10, 7]=>"Annetta", [12, 11]=>"Nicole", [2, 5]=>"Alison", [0, 1]=>"Wilma", [1, 3]=>"Shana", [3, 7]=>"Judd", [4, 9]=>"Lucio", [5, 11]=>"Hardy", [19, 10]=>"Immanuel", [9, 0]=>"Uriel", [8, 2]=>"Milton", [12, 10]=>"Elody", [5, 10]=>"Alexanne", [1, 2]=>"Lauretta", [0, 0]=>"Louvenia", [2, 4]=>"Adelia", [21, 5]=>"Erling", [18, 11]=>"Corene", [22, 3]=>"Haskell", [11, 11]=>"Leta", [10, 9]=>"Terrence", [14, 1]=>"Giuseppe", [15, 3]=>"Silas", [12, 5]=>"Johnnie", [4, 11]=>"Aurelie", [5, 9]=>"Meggie", [2, 7]=>"Phoebe", [0, 3]=>"Sister", [1, 1]=>"Violet", [3, 5]=>"Lilian", [18, 10]=>"Eusebio", [11, 10]=>"Emma", [15, 2]=>"Theodore", [14, 0]=>"Cassidy", [4, 10]=>"Edmund", [2, 6]=>"Claire", [0, 2]=>"Madisen", [1, 0]=>"Kasey", [3, 4]=>"Elijah", [17, 11]=>"Susana", [20, 1]=>"Nicklaus", [21, 3]=>"Kelsie", [10, 11]=>"Garnett", [11, 9]=>"Emanuel", [15, 1]=>"Louvenia", [14, 3]=>"Otho", [13, 5]=>"Vincenza", [3, 11]=>"Tate", [2, 9]=>"Beau", [5, 7]=>"Jason", [6, 1]=>"Jayde", [7, 3]=>"Lamont", [4, 5]=>"Curt", [17, 10]=>"Mack", [21, 2]=>"Lilyan", [10, 10]=>"Ruthe", [14, 2]=>"Georgianna", [4, 4]=>"Nyasia", [6, 0]=>"Sadie", [16, 11]=>"Emil", [21, 1]=>"Melba", [20, 3]=>"Delia", [3, 10]=>"Rosalee", [2, 8]=>"Myrtle", [7, 2]=>"Rigoberto", [14, 5]=>"Jedidiah", [13, 3]=>"Flavie", [12, 1]=>"Evie", [8, 9]=>"Olaf", [9, 11]=>"Stan", [20, 2]=>"Judge", [5, 5]=>"Cassie", [7, 1]=>"Gracie", [6, 3]=>"Armando", [4, 7]=>"Delia", [3, 9]=>"Marley", [16, 10]=>"Robyn", [2, 11]=>"Richie", [12, 0]=>"Gilberto", [13, 2]=>"Dedrick", [9, 10]=>"Liam", [5, 4]=>"Jabari", [7, 0]=>"Enola", [6, 2]=>"Lela", [3, 8]=>"Jade", [2, 10]=>"Johnson", [15, 5]=>"Willow", [12, 3]=>"Fredrick", [13, 1]=>"Beau", [9, 9]=>"Carlie", [8, 11]=>"Daisha", [6, 5]=>"Declan", [4, 1]=>"Carolina", [5, 3]=>"Cruz", [7, 7]=>"Jaime", [0, 9]=>"Anthony", [1, 11]=>"Esta", [13, 0]=>"Shaina", [12, 2]=>"Alec", [8, 10]=>"Lora", [6, 4]=>"Emely", [4, 0]=>"Rodger", [5, 2]=>"Cedrick", [0, 8]=>"Collin", [1, 10]=>"Armani", [16, 5]=>"Brooks", [19, 3]=>"Eleanora", [18, 1]=>"Alva", [7, 5]=>"Melissa", [5, 1]=>"Tabitha", [4, 3]=>"Aniya", [6, 7]=>"Marc", [1, 9]=>"Marjorie", [0, 11]=>"Arvilla", [19, 2]=>"Adela", [7, 4]=>"Zakary", [5, 0]=>"Emely", [4, 2]=>"Alison", [1, 8]=>"Lorenz", [0, 10]=>"Lisandro", [17, 5]=>"Aylin", [18, 3]=>"Giles", [19, 1]=>"Kyleigh", [8, 5]=>"Mary", [11, 3]=>"Claire", [10, 1]=>"Avis", [9, 7]=>"Manuela", [15, 11]=>"Chesley", [18, 2]=>"Kristopher", [24, 3]=>"Zola", [8, 4]=>"Pietro", [10, 0]=>"Delores", [11, 2]=>"Timmy", [15, 10]=>"Khalil", [18, 5]=>"Trudie", [17, 3]=>"Rafael", [16, 1]=>"Anthony"} What I need to do though, is basically remove all the empty entries. Let's say [17,3] = Raphael does not have an element in front of if (let's say - no [16,3] exists) then [17,3] should become [16,3] etc. So basically all empty items will be popped off the vertical (row) structure of the hash. Are there functions I should have a look at or is there an easy squash-like method that would just remove blanks and adjust and move other items? Thanks in advance for your help.

  Read the article

• NHibernate save / update event listeners: listening for child object saves

  - by James Allen

  I have an Area object which has many SubArea children: public class Area { ... public virtual IList<SubArea> SubAreas { get; set; } } he children are mapped as a uni-directional non-inverse relationship: public class AreaMapping : ClassMap<Area> { public AreaMapping() { HasMany(x => x. SubAreas).Not.Inverse().Cascade.AllDeleteOrphan(); } } The Area is my aggregate root. When I save an area (e.g. Session.Save(area) ), the area gets saved and the child SubAreas automatically cascaded. I want to add a save or update event listener to catch whenever my areas and/or subareas are persisted. Say for example I have an area, which has 5 SubAreas. If I hook into SaveEventListeners: Configuration.EventListeners.SaveEventListeners = new ISaveOrUpdateEventListener[] { mylistener }; When I save the area, Mylistener is only fired once only for area (SubAreas are ignored). I want the 5 SubAreas to be caught aswell in the event listener. If I hook into SaveOrUpdateEventListeners instead: Configuration.EventListeners.SaveOrUpdateEventListeners = new ISaveOrUpdateEventListener[] { mylistener }; When I save the area, Mylistener is not fired at all. Strangely, if I hook into SaveEventListeners and SaveOrUpdateEventListeners: Configuration.EventListeners.SaveEventListeners = new ISaveOrUpdateEventListener[] { mylistener }; Configuration.EventListeners.SaveOrUpdateEventListeners = new ISaveOrUpdateEventListener[] { mylistener }; When I save the area, Mylistener is fired 11 times: once for the area, and twice for each SubArea! (I think because NHIbernate is INSERTing the SubArea and then UPDATING with the area foreign key). Does anyone know what I'm doing wrong here, and how I can get the listener to fire once for each area and subarea?

  Read the article

• Why are floating point values so prolific?

  - by Kibbee

  So, title says it all. Why are floating point values so prolific in computer programming. Due to problems like rounding errors, and not being able to even accurately represent numbers such as 0.1, I really can't see how they got as far as they did. I understand that the computation is faster with floating point numbers, however, I can think of only a few cases that they actually the right data type would be using. If you sat back and think about every time you used a floating point value, how many times did you say, well, some error would be ok, as long as the result was a few microseconds faster. It really makes me think because Jeff was talking about NP completeness, and how heuristics give an answer that is kind of right. And well, computers shouldn't do that. They should give you the answer that is correct. Yet we see floating point values used in many applications where they are completely not valid. What really bugs me, isn't that floating point exists, but that in many languages, there isn't even a viable alternative, non-floating point, decimal value. A lot of programmers when doing financial applications have to fall back to storing the number of cents in an integer field. Which brings with it all kinds of other problems. Why do floats continue to be so prolific, even though they can't represent the real answer, and we expect computers to be accurate? [EDIT] Just to clarify, I was talking about Base 2 floating points, and not base 10 floating points. .Net offers the Decimal data type, which is a base 10 floating point value which offers a much better representation of the numbers we deal with on a daily basis in most computer programs. I find it hard to believe that even modern languages like Java don't support base 10 floating point values, unless you want to move into the realm of things like BigDecimal, which isn't really the right answer either in a lot of situations.

  Read the article

• what's the alternative to readonlycollection when using lazy="extra"?

  - by Kunjan

  I am trying to use lazy="extra" for the child collection of Trades I have on my Client object. The trades is an Iset<Trade Trades, exposed as ReadOnlyCollection<Trade because I do not want anyone to modify the collection directly. As a result, I have added AddTrade and RemoveTrade methods. Now I have a Client Search page where I need to show the Trade Count. and on the Client details page I have a tab where I need to show all the trades for the Client in paged gridview. What I want to achieve is, for the search when I say on the client object as client.Trades.Count, nHibernate should only fire a select count(*) query. Hence I am using lazy="extra". But because I am using a ReadOnlyCollection, nHibernate fires a count query & a separate query to load the child collection trades completely. Also, I cannot include the Trades in my initial search request as this would disturb the paging because a counterparty can have n trades which would result in n rows, when I am searching clients only. So the child collections have to be loaded lazily. The second problem is that on the client details page -- Trades grid view, I have enabled paging for performance reasons. But by nature nHibernate loads the entire collection of trades as the user goes from one page to another. Ideally I want to control this by getting only trades specific to the page the user is on. How can I achieve this? I came across this very good article. http://stackoverflow.com/questions/876976/implementing-ipagedlistt-on-my-models-using-nhibernate But I am not sure if this will work for me, as lazy=extra currently doesnt work as expected with the ReadOnlyCollection. So, if I went ahead and implemented the solution this way and further enhanced it by making the List/Set Immutable, will lazy=extra give me the same problem as with ReadOnlyCollections?

  Read the article

• LINQ to SQL: filter nested objects with soft deletes

  - by Alex

  Hello everyone, I'm using soft deleting in my database (IsDeleted field). I'm actively using LoadWith and AssociateWith methods to retrieve and filter nested records. The thing is AssociateWith only works with properties that represents a one-to-many relationship. DataLoadOptions loadOptions = new DataLoadOptions(); loadOption.LoadWith<User>(u = > u.Roles); loadOption.AssociateWith<User>(u = > u.Roles.Where(r = > !r.IsDeleted)); In the example above I just say: I want to retrieve users with related (undeleted) roles. But when I have one-to-one relationship, e.g. Document - File (the only one file is related to the document) I'm unable to filter soft deleted object: DataLoadOptions loadOptions = new DataLoadOptions(); loadOption.LoadWith<Document>(d = > d.File); // the next certainly won't work loadOption.AssociateWith<File>(f = > !f.IsDeleted); So, is there any idea how to filter records within the one-to-one relationship? Thanks!

  Read the article

• Using an existing IQueryable to create a new dynamic IQueryable

  - by dnoxs

  I have a query as follows: var query = from x in context.Employees where (x.Salary > 0 && x.DeptId == 5) || x.DeptId == 2 order by x.Surname select x; The above is the original query and returns let's say 1000 employee entities. I would now like to use the first query to deconstruct it and recreate a new query that would look like this: var query = from x in context.Employees where ((x.Salary > 0 && x.DeptId == 5) || x.DeptId == 2) && (x,i) i % 10 == 0 order by x.Surname select x.Surname; This query would return 100 surnames. The syntax is probably incorrect, but what I need to do is attach an additional where clause and modify the select to a single field. I've been looking into the ExpressionVisitor but I'm not entirely sure how to create a new query based on an existing query. Any guidance would be appreciated. Thanks you.

  Read the article

• Scheme homework Black jack help....

  - by octavio

  So I need to do a game of blackjack simulator, butt can't seem to figure out whats wrong with the shuffle it's suppose to take a card randomly from the pack the put it on top of the pack. The delete it from the rest. so : (ace)(2)(3)(4)(5)...(k) if random card is let say 5 (5)(ace)(2)(3)(4)(5)...(k) then it deletes the 2nd 5 (5)(ace)(2)(3)(4)(6)...(k) here is the code: (define deck '((A . C) (2 . C) (3 . C) (4 . C) (5 . C) (6 . C) (7 . C) (8 . C) (9 . C) (10 . C) (V . C) (Q . C) (K . C))) ;auxilliary function for shuffle let you randomly select a card. (define shuffAux (lambda (t) (define cardR (lambda (t) (list-ref t (random 13)))) (cardR t))) ;auxilliary function used to remove the card after the car to prevent you from removing the randomly selected from the car(begining of the deck). (define (removeDupC card deck) (delete card (cdr deck)) ) (define shuffle2ndtry (lambda (deck seed) (define do-shuffle (lambda (deck seed) (if (> seed 0)( (cons (shuffAux deck) deck) (removeDupC (car deck) deck) (- 1 seed)) (write deck) ) ) ) (do-shuffle deck seed))) (define (shuffle deck seed) (define cards (cons (shuffAux deck) deck)) (write cards) (case (> seed 0) [(#t) (removeDupC (car cards) (cdr cards)) (shuffle cards (- seed 1))] [(#f) (write cards)])) (define random (let ((seed 0) (a 3141592653) (c 2718281829) (m (expt 2 35))) (lambda (limit) (cond ((and (integer? limit)) (set! seed (modulo (+ (* seed a) c) m)) (quotient (* seed limit) m)) (else (/ (* limit (random 34359738368)) 34359738368)))))) ;function in which you can delete an element from the list. (define delete (lambda (item list) (cond ((equal? item (car list)) (cdr list)) (else (cons (car list) (delete item (cdr list))))))) (

  Read the article

• Debugging a working program on Mathematica 5 with Mathematica 7

  - by Neuschwanstein

  Hi everybody, I'm currently reading the Mathematica Guidebooks for Programming and I was trying to work out one of the very first program of the book. Basically, when I run the following program: Plot3D[{Re[Exp[1/(x + I y)]]}, {x, -0.02, 0.022}, {y, -0.04, 0.042}, PlotRange -> {-1, 8}, PlotPoints -> 120, Mesh -> False, ColorFunction -> Function[{x1, x2, x3}, Hue[Arg[Exp[1/(x1 + I x2)]]]]] either I get a 1/0 error and e^\infinity error or, if I lower the PlotPoints options to, say, 60, an overflow error. I have a working output though, but it's not what it's supposed to be. The hue seems to be diffusing off the left corner whereas it should be diffusing of the origin (as can be seen on the original output) Here is the original program which apparently runs on Mathematica 5 (Trott, Mathematica Guidebook for Programming): Off[Plot3D::gval]; Plot3D[{Re[Exp[1/(x + I y)]], Hue[Arg[Exp[1/(x + I y)]]]}, {x, -0.02, 0.022}, {y, -0.04, 0.042}, PlotRange -> {-1, 8}, PlotPoints -> 120, Mesh -> False] Off[Plot3D::gval]; However, ColorFunction used this way (first Plot3D argument) doesn't work and so I tried to simply adapt to its new way of using it. Well, thanks I guess!

  Read the article

• help in the Donalds B. Johnson's algorithm, i cannot understand the pseudo code (PART II)

  - by Pitelk

  Hi all , i cannot understand a certain part of the paper published by Donald Johnson about finding cycles (Circuits) in a graph. More specific i cannot understand what is the matrix Ak which is mentioned in the following line of the pseudo code : Ak:=adjacency structure of strong component K with least vertex in subgraph of G induced by {s,s+1,....n}; to make things worse some lines after is mentins " for i in Vk do " without declaring what the Vk is... As far i have understand we have the following: 1) in general, a strong component is a sub-graph of a graph, in which for every node of this sub-graph there is a path to any node of the sub-graph (in other words you can access any node of the sub-graph from any other node of the sub-graph) 2) a sub-graph induced by a list of nodes is a graph containing all these nodes plus all the edges connecting these nodes. in paper the mathematical definition is " F is a subgraph of G induced by W if W is subset of V and F = (W,{u,y)|u,y in W and (u,y) in E)}) where u,y are edges , E is the set of all the edges in the graph, W is a set of nodes. 3)in the code implementation the nodes are named by integer numbers 1 ... n. 4) I suspect that the Vk is the set of nodes of the strong component K. now to the question. Lets say we have a graph G= (V,E) with V = {1,2,3,4,5,6,7,8,9} which it can be divided into 3 strong components the SC1 = {1,4,7,8} SC2= {2,3,9} SC3 = {5,6} (and their edges) Can anybody give me an example for s =1, s= 2, s= 5 what if going to be the Vk and Ak according to the code? The pseudo code is in my previous question in http://stackoverflow.com/questions/2908575/help-in-the-donalds-b-johnsons-algorithm-i-cannot-understand-the-pseudo-code and the paper can be found at http://stackoverflow.com/questions/2908575/help-in-the-donalds-b-johnsons-algorithm-i-cannot-understand-the-pseudo-code thank you in advance

  Read the article

• Qt: Force QWebView to click on a web element, even one not visible on the window

  - by Pirate for Profit

  So let's say I'm trying to click a link in the QWebView, here is what I have: // extending QWebView void MyWebView::click(const QString &selectorQuery) { QWebElement el = this->page()->mainFrame()->findFirstElement(selectorQuery); if (!el) return; el.setFocus(); QMouseEvent pressEvent(QMouseEvent::MouseButtonPress, el.geometry().center(), Qt::MouseButton::LeftButton, Qt::LeftButton, Qt::NoModifier); QCoreApplication::sendEvent(this, &pressEvent); QMouseEvent releaseEvent(QMouseEvent::MouseButtonRelease, el.geometry().center(), Qt::MouseButton::LeftButton, Qt::LeftButton, Qt::NoModifier); QCoreApplication::sendEvent(this, &releaseEvent); } And you call it as so: myWebView->click("a[href]"); // will click first link on page myWebView->click("input[type=submit]"); // submits a form THE ONLY PROBLEM IS: if the element is not visible in the window, it is impossible to click. What I mean is if you have to scroll down to see it, you can't click it. I imagine this has to do with the geometry, since the element doesn't show up on the screen it can't do the math to click it right. Any ideas to get around this? Maybe some way to make the window behave like a billion x billion pixels but still look 200x200?

  Read the article

• Facebook with RestFB (Java)

  - by Trick

  I just began to use this and I already stumbled on some from-my-side-strange errors. I am using RestFB jar. My problem is, that I can not get my session key (this is the start of everything :)). FacebookClient facebookClient = new DefaultFacebookClient(API_KEY, SECRET_KEY); try { String token = facebookClient.execute("auth.createToken", String.class, Parameter.with("null", "null")); System.out.println(token); String session = facebookClient.execute("auth.getSession", String.class, Parameter.with("auth_token", token)); System.out.println(session); } catch (FacebookException e) { e.printStackTrace(); } I get the token correctly. Parameter.with("null,"null") is there because it demands at least one, but method for creating token doesn't expect any. When trying to get the session key, I get the following error: com.restfb.FacebookResponseStatusException: Received Facebook error response (code 100): Invalid parameter at com.restfb.DefaultFacebookClient.throwFacebookResponseStatusExceptionIfNecessary(DefaultFacebookClient.java:357) at com.restfb.DefaultFacebookClient.makeRequest(DefaultFacebookClient.java:320) at com.restfb.DefaultFacebookClient.execute(DefaultFacebookClient.java:188) at com.restfb.DefaultFacebookClient.execute(DefaultFacebookClient.java:178) Documentation for getting session doesn't say any more parameters are required! Did anybody already try this JAR or do you have any other solution for Java? EDIT: Does the application needs to be "published" in searchers to be able to do this??

  Read the article

• Good grammar for date data type for recursive descent parser LL(1)

  - by Totophil

  I'm building a custom expression parser and evaluator for production enviroment to provide a limited DSL to the users. The parser itself as the DSL, need to be simple. The parser is going to be built in an exotic language that doesn't support dynamic expression parsing nor has any parser generator tools available. My decision is to go for recursive descent approach with LL(1) grammar, so that even programmers with no previous experience in evaluating expression could quickly learn how the code works. It has to handle mixed expressions made up of several data types: decimals, percentages, strings and dates. And dates in the format of dd/mm/yyyy are easy to confuse with a string of devision ops. Is where a good solution to this problem? My own solution that is aimed at keeping the parser simple involves prefixing dates with a special symbol, let's say apostrophe: <date> ::= <apostr><digit><digit>/<digit><digit>/<digit><digit><digit><digit> <apostr> ::= ' <digit> ::= '0'..'9'

  Read the article

• Django: Complex filter parameters or...?

  - by minder

  This question is connected to my other question but I changed the logic a bit. I have models like this: from django.contrib.auth.models import Group class Category(models.Model): (...) editors = ForeignKey(Group) class Entry(models.Model): (...) category = ForeignKey(Category) Now let's say User logs into admin panel and wants to change an Entry. How do I limit the list of Entries only to those, he has the right to edit? I mean: How can I list only those Entries which are assigned to a Category that in its "editors" field has one of the groups the User belongs to? What if User belongs to several groups? I still need to show all relevant Entries. I tried experimenting with changelist_view() and queryset() methods but this problem is a bit too complex for me. I'm also wondering if granular-permissions could help me with the task, but for now I have no clue. I came up only with this: First I get the list of all Groups the User belongs to. Then for each Group I get all connected Categories and then for each Category I get all Entries that belong to these Categories. Unfortunately I have no idea how to stitch everything together as filter() parameters to produce a nice single QuerySet.

  Read the article

• gnuplot: display only the roots.

  Hi, Gnuplot, a great package ... I'm in love with it. But we can have our tiffs as well, as any couple :-) This time, I wanted to simply plot the roots of an equation: say a quadratic to keep things simple. However, I only want two nice round dots appearing on the x-axis representing the point where the quadratic crosses the x-axis or y=0 axis. In other words the roots (when they are real that is). I don't want to do this with datafile ... I want gnuplot to calculate the roots and plot them. First off, my attempts: single points aren't really what gnuplot would have you plot, it likes a good wide range of values. Preferably filling up the whole width of your canvas. It's possible to locate a rectangle at a certain coordinate on your plot, but I wanted a round point. Currently I'm chasing up how to do a tiny filled polygon at that point. I have tried the "samples" option bu it doesn't seem useful. Also though about defining a dirac-delta function so that only one point would be highlighted (though two would be needed). ANy suggestions welcome, thanks.

  Read the article

• How to pass a reference to a JS function as an argument to an ExternalInterface call?

  - by Ryan Wilson

  Summary I want to be able to call a JavaScript function from a Flex app using ExternalInterface and pass a reference to a different JavaScript function as an argument. Base Example Given the following JavaScript: function foo(callback) { // ... do some stuff callback(); } function bar() { // do some stuff that should happen after a call to foo } I want to call foo from my flex app using ExternalInterface and pass a reference to bar as the callback. Why Really,foo is not my function (but, rather, FB.Connect.showBookmarkDialog), which due to restrictions on Facebook iframe apps can only be called on a button click. My button, for design reasons, is in the Flex app. Fortunately, it's possible to call ExternalInterface.call("FB.Connect.showBookmarkDialog", callback) to display the bookmark dialog. But, FB.Connect.showBookmarkDialog requires a JS callback so, should I want to receive a callback (which I do), I need to pass a reference to a JS function as the single argument. Real Example MXML: <mx:Button click="showBookmarkDialog();" /> ActionScript: function showBookmarkDialog() : void { ExternalInterface.registerCallback( "onBookmarkDialogClosed", onBookmarkDialogClosed ); ExternalInterface.call( "FB.Connect.showBookmarkDialog", /* ref to JS function onBookmarkDialogClosed ? */ ); } function onBookmarkDialogClosed(success:Boolean) : void { // sweet, we made it back } JavaScript: function onBookmarkDialogClosed() { var success; // determine value of success getSWF().onBookmarkDialogClosed(success); } Failed Experiments I have tried... ExternalInterface.call( "FB.Connect.showBookmarkDialog", "onBookmarkDialogClosed" ); ExternalInterface.call( "FB.Connect.showBookmarkDialog", onBookmarkDialogClosed ); ExternalInterface.call( "FB.Connect.showBookmarkDialog", function() : void { ExternalInterface.call("onBookmarkDialogClosed"); } ); ExternalInterface.call( "FB.Connect.showBookmarkDialog", function() { this["onBookmarkDialogClosed"](); } ); Of note: Passing a string as the argument to an ExternalInterface call results in FB's JS basically trying to do `"onBookmarkDialogClosed"()` which, needless to say, will not work. Passing a function as the argument results in a function object on the other side (confirmable with `typeof`), but it seems to be an empty function; namely, `function Function() {}`

  Read the article

• Progress Bar design patterns?

  - by shoosh

  The application I'm writing performs a length algorithm which usually takes a few minutes to finish. During this time I'd like to show the user a progress bar which indicates how much of the algorithm is done as precisely as possible. The algorithm is divided into several steps, each with its own typical timing. For instance- initialization (500 milli-sec) reading inputs (5 sec) step 1 (30 sec) step 2 (3 minutes) writing outputs (7 sec) shutting down (10 milli-sec) Each step can report its progress quite easily by setting the range its working on, say [0 to 150] and then reporting the value it completed in its main loop. What I currently have set up is a scheme of nested progress monitors which form a sort of implicit tree of progress reporting. All progress monitors inherit from an interface IProgressMonitor: class IProgressMonitor { public: void setRange(int from, int to) = 0; void setValue(int v) = 0; }; The root of the tree is the ProgressMonitor which is connected to the actual GUI interface: class GUIBarProgressMonitor : public IProgressMonitor { GUIBarProgressMonitor(ProgressBarWidget *); }; Any other node in the tree are monitors which take control of a piece of the parent progress: class SubProgressMonitor : public IProgressMonitor { SubProgressMonitor(IProgressMonitor *parent, int parentFrom, int parentLength) ... }; A SubProgressMonitor takes control of the range [parentFrom, parentFrom+parentLength] of its parent. With this scheme I am able to statically divide the top level progress according to the expected relative portion of each step in the global timing. Each step can then be further subdivided into pieces etc' The main disadvantage of this is that the division is static and it gets painful to make changes according to variables which are discovered at run time. So the question: are there any known design patterns for progress monitoring which solve this issue?

  Read the article

• Language+IDE for teaching high school students?

  - by daveagp

  I'm investigating languages and IDEs for a project involving teaching high-school students (around grade 11). It will teach basics of programming as an introduction to computer science (e.g., including how numbers/strings/characters are represented, using procedures and arrays, control flow, a little bit of algorithms, only very basic I/O). The non-negotiable requirements for this project are: a free up-to-date cross-platform IDE (Win & Mac incl. 64-bit) with debug a compiler where it's easy to learn from your mistakes together with the IDE, a gentle installation+learning curve So far, the best options I see are the following. Are there others I should know about? I am giving a short explanation with each one to generally show what I am looking for. In order from most to least promising: Pascal + FreePascal IDE (it seems a little buggy but actively developed?) Python + Eclipse + PyDev (good but features are overwhelming/hard to navigate) Groovy + Eclipse ('') Python + IDLE (looks unnatural to do debugging, to me) Pascal + Lazarus (IDE overwhelming, e.g. not obvious how to "start from scratch") Preferably, as a rule of thumb, the language should be direct enough that you don't need to wrap every program in a class, don't need to reference a System object to println, etc. I tried a little bit to see if there is something in JavaScript or (non-Visual) Basic along the lines of what I want, but found nothing so far. I would say that C/C++/C#, Java, Ruby, Lisp, VB do not fit my criteria for languages for this project. To reiterate my questions: are any of those 5 options really awesome or un-awesome? Are there other options which are even MORE awesome? Anything for Basic or JavaScript which meets all of the criteria? Thanks!

  Read the article

• VS Solution and Mercurial repository layout for a c# project with plugins and external libraries.

  - by Joviee

  I'm developing a project in .NET (using C# to be more specific). Using Visual Studio as an IDE. Using Mercurial for version control. I'll be using some third-party libraries: ThirdParty.Foo.dll ThirdParty.Bar.dll ThirdParty.Baz.dll And some in-house libraries: Company.A Company.B Company.C Company.D (References third party libraries) Company.E (References Company.A) The project itself will have the following components: Project.Core Project.DataModel (references in-house/third-party libraries) Project.GUI (references Core, DataModel, and in-house/third-party libraries) Project.PluginOne (references Core, DataModel, and in-house/third-party libraries) Project.PluginTwo (references Core, DataModel, and in-house/third-party libraries) * can be an arbitrary number of plugins * I'm quite new to Mercurial, so I don't really know the best way to structure my repositories for a project like this, with a lot of interconnected components. The in-house libraries are fairly distinct, so I would say that each one of them should have its own repository. However, some of them use functionality provided by others. How should these dependencies be managed? The project plug-ins should be distinct from eachother, so I'd imagine that each would have its own repository. How should the dependencies on the in-house/third-party libraries and the rest of the project (Project.DataModel and Project.Core) be managed, with regards to the solution layout and the repository layout? So basically, for a project like this, what are the best way of structuring: (a) my visual studio solutions (b) my source control repository/repositories

  Read the article

• NSXMLParser: how do I wait until loading has finished?

  - by Archagon

  Let's say I'm using NSXMLParser to load a level (stored as an XML document, obviously) into my iPhone game. NSXMLParser works by assigning a delegate and sending it messages at key moments. How do I ensure that my entire level is loaded before doing anything else? I know I can make my main class the delegate and implement parserDidEndDocument, but this feels very hacky. My main class shouldn't have to know anything about the way the parsing is done! On the other hand, if I make a separate class/delegate for parsing my level, my main class has no way of knowing when the parsing is finished, unless it queries the parsing class continuously or the parsing class sends it a message. Either way, the main class would be tied to the implementation of the parsing class. Can I hide all this event-driven business from the main class and simply make the parser return the level object when it's done? (i.e., newLevel = [[GameLevel alloc] initFromXML:xmlfile], which would in turn use NSXMLParser to load the level and then somehow return when finished.) At the moment, I'm using an external DOM parser, but I'm curious how this would be done with NSXMLParser. Sorry if this is a stupid question -- I'm a bit new to this!

  Read the article

• Large number of simultaneous long-running operations in Qt

  - by Hostile Fork

  I have some long-running operations that number in the hundreds. At the moment they are each on their own thread. My main goal in using threads is not to speed these operations up. The more important thing in this case is that they appear to run simultaneously. I'm aware of cooperative multitasking and fibers. However, I'm trying to avoid anything that would require touching the code in the operations, e.g. peppering them with things like yieldToScheduler(). I also don't want to prescribe that these routines be stylized to be coded to emit queues of bite-sized task items...I want to treat them as black boxes. For the moment I can live with these downsides: Maximum # of threads tend to be O(1000) Cost per thread is O(1MB) To address the bad cache performance due to context-switches, I did have the idea of a timer which would juggle the priorities such that only idealThreadCount() threads were ever at Normal priority, with all the rest set to Idle. This would let me widen the timeslices, which would mean fewer context switches and still be okay for my purposes. Question #1: Is that a good idea at all? One certain downside is it won't work on Linux (docs say no QThread::setPriority() there). Question #2: Any other ideas or approaches? Is QtConcurrent thinking about this scenario? (Some related reading: how-many-threads-does-it-take-to-make-them-a-bad-choice, many-threads-or-as-few-threads-as-possible, maximum-number-of-threads-per-process-in-linux)

  Read the article

• SQL Server 2005 and 'General network error'

  - by Mariusz

  I know there is a lot of information in the Internet about solving this problem, but it didn't help me. My Delphi application uses dbExpress controls to access the database and execute SQL queries. Once every couple of days, however, it stops working because the database connection fails. This happens on several different computers with different versions of Windows. MSSQL Server 2005 (version 9.0.4035) is installed on each of them. The above mentioned application executes queries every couple of seconds, and they are mainly insert commands. Every couple of days I get a series of exceptions like the following one: [DBNETLIB][ConnectionOpen (PreLoginHandshake()).]General network error. Check your network documentation. And then the SQL server becomes inaccessible until I restart it manually. The information I found in the Internet say that I should install some service packs, change some registry entries etc., but believe me, none of these helps and I don't know what else to do now. Could you please help me solve this problem? Any clues or ideas? I can give you some more information about the server or the application if necessary. Thank you very much in advance.

  Read the article

• Regression Testing and Deployment Strategy

  - by user279516

  I'd like some advice on a deployment strategy. If a development team creates an extensive framework, and many (20-30) applications consume it, and the business would like application updates at least every 30 days, what is the best deployment strategy? The reason I ask is that there seems to be a lot of waste (and risk) in using an agile approach of deploying changes monthly, if 90% of the applications don't change. What I mean by this is that the framework can change during the month, and so can a few applications. Because the framework changed, all applications should be regression-tested. If, say, 10 of the applications don't change at all during the year, then those 10 applications are regression-tested EVERY MONTH, when they didn't have any feature changes or hot fixes. They had to be tested simply because the business is rolling updates every month. And the risk that is involved... if a mission-critical application is deployed, that takes a few weeks, and multiple departments, to test, is it realistic to expect to have to constantly regression-test this application? One option is to make any framework updates backward-compatible. While this would mean that applications don't need to change their code, they would still need to be tested because the underlying framework changed. And the risk involved is great; a constantly changing framework (and deploying this framework) means the mission-critical app can never just enjoy the same code base for a long time. These applications share the same database, hence the need for the constant testing. I'm aware of TDD and automated tests, but that doesn't exist at the moment. Any advice?

  Read the article

• Reachability sometimes fails, even when we do have an internet connection

  - by stoutyhk

  Hi I've searched but can't see a similar question. I've added a method to check for an internet connection per the Reachability example. It works most of the time, but when installed on the iPhone, it quite often fails even when I do have internet connectivity (only when on 3G/EDGE - WiFi is OK). Basically the code below returns NO. If I switch to another app, say Mail or Safari, and connect, then switch back to the app, then the code says the internet is reachable. Kinda seems like it needs a 'nudge'. Anyone seen this before? Any ideas? Many thanks James + (BOOL) doWeHaveInternetConnection{ BOOL success; // google should always be up right?! const char *host_name = [@"google.com" cStringUsingEncoding:NSASCIIStringEncoding]; SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithName(NULL, host_name); SCNetworkReachabilityFlags flags; success = SCNetworkReachabilityGetFlags(reachability, &flags); BOOL isAvailable = success && (flags & kSCNetworkFlagsReachable) && !(flags & kSCNetworkFlagsConnectionRequired); if (isAvailable) { NSLog(@"Google is reachable: %d", flags); }else{ NSLog(@"Google is unreachable"); } return isAvailable; }

  Read the article

< Previous Page | 657 658 659 660 661 662 663 664 665 666 667 668  | Next Page >