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  • Problem with logicalOR ( regex ) not greedy

    - by Marin Doric
    This is the part of a string "21xy5". I want to insert " * " surrounded with whitespace between: digit and letter, letter and digit, letter and letter. I use this regex pattern "\d[a-z]|[a-z]\d|[a-z][a-z]" to find indexs where I gona insert string " * ". Problem is that when regex OR(|) in string 21xy5 trays to match 21-x|x-y|y-5, when first condition 21-x success, second x-y is not checked, and third success. So I have 21 * xy * 5 instead 21 * x * y * 5. If input string is like this xy21, then x-y success and then I have x * y21. Problem is that logical OR is not greedy. Regex reg = new Regex(@"\d[a-z]|[a-z]\d|[a-z][a-z]" ); MatchCollection matchC; matchC = reg.Matches(input); int ii = 1; foreach (Match element in matchC) { input = input.Insert(element.Index + ii, " * "); ii += 3; } return input;

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  • python - tkinter - update label from variable

    - by Tom
    I wrote a python script that does some stuff to generate and then keep changing some text stored as a string variable. This works, and I can print the string each time it gets changed. Problems have arisen while trying to display that output in a GUI (just as a basic label) using tkinter. I can get the label to display the string for the first time... but it never updates. This is really the first time I have tried to use tkinter, so it's likely I'm making a foolish error. What I've got looks logical to me, but I'm evidently going wrong somewhere! from tkinter import * outputText = 'Ready' counter = int(0) root = Tk() root.maxsize(400, 400) var = StringVar() l = Label(root, textvariable=var, anchor=NW, justify=LEFT, wraplength=398) l.pack() var.set(outputText) while True: counter = counter + 1 #do some stuff that generates string as variable 'result' outputText = result #do some more stuff that generates new string as variable 'result' outputText = result #do some more stuff that generates new string as variable 'result' outputText = result if counter == 5: break root.mainloop() I also tried: from tkinter import * outputText = 'Ready' counter = int(0) root = Tk() root.maxsize(400, 400) var = StringVar() l = Label(root, textvariable=var, anchor=NW, justify=LEFT, wraplength=398) l.pack() var.set(outputText) while True: counter = counter + 1 #do some stuff that generates string as variable 'result' outputText = result var.set(outputText) #do some more stuff that generates new string as variable 'result' outputText = result var.set(outputText) #do some more stuff that generates new string as variable 'result' outputText = result var.set(outputText) if counter == 5: break root.mainloop() In both cases, the label will show 'Ready' but won't update to change that to the strings as they're generated later. After a fair bit of googling and looking through answers on this site, I thought the solution might be to use update_idletasks - I tried putting that in after each time the variable was changed, but it didn't help. It also seems possible I am meant to be using trace and callback somehow to make all this work...but I can't get my head around how that works (I tried, but didn't manage to make anything that even looked like it would do something, let alone actually worked). I'm still very new to both python and especially tkinter, so, any help much appreciated but please spell it out for me if you can :)

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  • Always can't separate these guys: ascending and descending! Are there good examples?

    - by mystify
    As a non-english dude, I have trouble differentiating this. When I try to translate this into my language, I get something weird like "go up" for ascending. So lets say I want to sort the names of all my pets alphabetically. I want that A comes first, then B, then C... and so on. So since the alphabet is not a number for me, my brain refuses to grok what's "going up". A = 0? B = 1? C = 2? If yes, then ascending would be what I'm most of the time looking for. Table would start showing A, then B, then C... Or is that the other way around? Must I look from the bottom of the table, up? And with numbers: If it's an ascending order, the smallest comes first? (would seem logical...) Can someone post a short but good example for what is an ascending sort order, and what is an descending sort order? And does that apply to whatever platform, programming language, API, etc.?

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  • One Model to Rule Them All - VS2010 UML, ADO.NET Entity Data Model, and T4

    - by Eric J.
    I worked on a fairly large project a while back where we modeled the classes in Enterprise Architect and generated the (partial) POCO classes (complete with model-driven business rule validations), persistence (NHibernate mapping file) and DDL. Based on certain model attributes we could flag alternate generation strategies or indicate that a particular portion would be entirely hand-coded. There was a good deal of initial investment, but it paid large dividends over the lifetime of a 15 developer, 3 year project. I'm investigating doing something similar with the current Microsoft technology stack. The place I'm stuck is that class modeling is done with the VS 2010 UML tools, but logical data modeling is done with Entity Data Modeler. Is it a reasonable path to use VS 2010 UML as the "single source of truth" and code generate the edmx files based on the class model? That's the inverse of the common path to create the entity model and use a POCO generator to generate classes. However, a good class model can be used to generate much more than just the properties so I tend to view it as a better choice than the entity model.

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  • Nested multithread operations tracing

    - by Sinix
    I've a code alike void ExecuteTraced(Action a, string message) { TraceOpStart(message); a(); TraceOpEnd(message); } The callback (a) could call ExecuteTraced again, and, in some cases, asynchronously (via ThreadPool, BeginInvoke, PLINQ etc, so I've no ability to explicitly mark operation scope). I want to trace all operation nested (even if they perform asynchronously). So, I need the ability to get last traced operation inside logical call context (there may be a lot of concurrent threads, so it's impossible to use lastTraced static field). There're CallContext.LogicalGetData and CallContext.LogicalSetData, but unfortunately, LogicalCallContext propagates changes back to the parent context as EndInvoke() called. Even worse, this may occure at any moment if EndInvoke() was called async. http://stackoverflow.com/questions/883486/endinvoke-changes-current-callcontext-why Also, there is Trace.CorrelationManager, but it based on CallContext and have all the same troubles. There's a workaround: use the CallContext.HostContext property which does not propagates back as async operation ended. Also, it does'nt clone, so the value should be immutable - not a problem. Though, it's used by HttpContext and so, workaround is not usable in Asp.Net apps. The only way I see is to wrap HostContext (if not mine) or entire LogicalCallContext into dynamic and dispatch all calls beside last traced operation. Help, please!

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  • What is your best-practice advice on implementing SQL stored procedures (in a C# winforms applicatio

    - by JYelton
    I have read these very good questions on SO about SQL stored procedures: When should you use stored procedures? and Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS’s? I am a beginner on integrating .NET/SQL though I have used basic SQL functionality for more than a decade in other environments. It's time to advance with regards to organization and deployment. I am using .NET C# 3.5, Visual Studio 2008 and SQL Server 2008; though this question can be regarded as language- and database- agnostic, meaning that it could easily apply to other environments that use stored procedures and a relational database. Given that I have an application with inline SQL queries, and I am interested in converting to stored procedures for organizational and performance purposes, what are your recommendations for doing so? Here are some additional questions in my mind related to this subject that may help shape the answers: Should I create the stored procedures in SQL using SQL Management Studio and simply re-create the database when it is installed for a client? Am I better off creating all of the stored procedures in my application, inside of a database initialization method? It seems logical to assume that creating stored procedures must follow the creation of tables in a new installation. My database initialization method creates new tables and inserts some default data. My plan is to create stored procedures following that step, but I am beginning to think there might be a better way to set up a database from scratch (such as in the installer of the program). Thoughts on this are appreciated. I have a variety of queries throughout the application. Some queries are incredibly simple (SELECT id FROM table) and others are extremely long and complex, performing several joins and accepting approximately 80 parameters. Should I replace all queries with stored procedures, or only those that might benefit from doing so? Finally, as this topic obviously requires some research and education, can you recommend an article, book, or tutorial that covers the nuances of using stored procedures instead of direct statements?

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  • Refactoring Bloated ViewModel

    - by Holy Christ
    Hi, I am writing a PRISM/MVVM/WPF application. It's a LOB application, so there are a lot of complicated rules. I've noticed the View Model is starting to get bloated. There are two main issues. One is that to maintain MVVM, I'm doing a lot of things that feel hacky like adding a bunch of properties to my VM. The view binds to those properties to keep track of what feels like view specific information. For example, a boolean keeping track of the status of a long running process in the VM, so the view can disable some of its controls while the long running process is working. I've read that this issue could be solved with Attached Behaviors. I'll look more into that. In the example MVVM apps you see online, this isn't a big deal because they are over-simplified. The other issue is the number of commands in my VM. Right now there are four commands. I'm defining the commands in the VM using Josh Smith's RelayCommand (basically the DelegateCommand in PRISM) so all the business logic lives in the VM. I considered moving each command into separate unit of works. I'm not sure the best way to do this. Which patterns are you guys using to keep your VMs clean? I can already feel someone responding with "your view and VM is too complicated, you should break them into many view/VMs". It is certainly not too complicated from a Ux perspective - there are 2 buttons, a combobox, and a listbox. Also, from a logical perspective, it is one cohesive domain. Having said that, I'm very interested in hearing how others are dealing with this type of issue. Thanks for your input.

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  • Cannot delete an image file that is shown in a listview

    - by Enrico
    Hello all, In my listview I show thumbnails of small images in a certain folder. I setup the listview as follows: var imageList = new ImageList(); foreach (var fileInfo in dir.GetFiles()) { try { var image = Image.FromFile(fileInfo.FullName); imageList.Images.Add(image); } catch { Console.WriteLine("error"); } } listView.View = View.LargeIcon; imageList.ImageSize = new Size(64, 64); listView.LargeImageList = imageList; for (int j = 0; j < imageList.Images.Count; j++) { var item = new ListViewItem {ImageIndex = j, Text = "blabla"}; listView.Items.Add(item); } The user can rightclick on an image in the listview to remove it. I remove it from the listview and then I want to delete this image from the folder. Now I get the error that the file is in use. Of course this is logical since the imagelist is using the file. I tried to first remove the image from the imagelist, but I keep on having the file lock. Can somebody tell me what I am doing wrong? Thanks!

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  • Project ideas for automated deduction/automated theorem proving?

    - by wsh
    Dear Stack Overflow brethren, I'm a second-semester junior who will embark upon my thesis soon, and I have an interest in automated deduction and automated theorem provers. As in, I'd like to advance the art in some way (I don't mean that pretentiously, but I do want to do something productive). I've Googled pretty far and wide and so far few promising ideas have emerged. There are a few student project idea pages, but most seem either horribly outdated or too advanced (I was originally going to attempt to synthesize postmodernist thought (hahaha) and abstract its logical content, build a complete and consistent model (if possible, of course), and attempt to automate it, grounding said model as possible in a nonstandard logic a la these. My advisor thought that gave postmodernist thought too much credit (a while ago I reimplemented the Postmodernism Generator in Haskell with Parsec, so that is in part where the idea came from); I am tempted to concur.) So, yeah. Does anyone have ideas? I apologize if there is some obvious gap in my approach here/if I haven't appropriately done my homework (and if there is one, please tell me!), but in large part I don't even know where to start, and thank you for reading all that.

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  • stock management of assemblys and its sub parts

    - by The Disintegrator
    I have to track the stock of individual parts and kits (assembly) and can't find a satisfactory way of doing this. Sample bogus and hyper simplified database: Table prod: prodID 1 prodName Flux capacitor prodCost 900 prodPrice 1350 (900*1.5) prodStock 3 - prodID 2 prodName Mr Fusion prodCost 300 prodPrice 600 (300*2) prodStock 2 - prodID 3 prodName Time travel kit prodCost 1650 (1350+300) prodPrice 2145 (1650*1.3) prodStock 2 Table rels relID 1 relSrc 1 (Flux capacitor) relType 4 (is a subpart of) relDst 3 (Time travel kit) - relID 2 relSrc 2 (Mr Fusion) relType 4 (is a subpart of) relDst 3 (Time travel kit) prodPrice: it's calculated based on the cost but not in a linear way. In this example for costs of 500 or less, the markup is a 200%. For costs of 500-1000 the markup is 150%. For costs of 1000+ the markup is 130% That's why the time travel kit is much cheaper than the individual parts prodStock: here is my problem. I can sell kits or the individual parts, So the stock of the kits is virtual. The problem when I buy: Some providers sell me the Time Travel kit as a whole (with one barcode) and some sells me the individual parts (with a different barcode) So when I load the stock I don't know how to impute it. The problem when I sell: If I only sell kits, calculate the stock would be easy: "I have 3 Flux capacitors and 2 Mr Fusions, so I have 2 Time travel kits and a Flux Capacitor" But I can sell Kits or individual parts. I have to track the stock of the individual parts and the possible kits at the same time (and I have to compensate for the sell price) Probably this is really simple, but I can't see a simple solution. Resuming: I have to find a way of tracking the stock and the database/program is the one who has to do it (I cant ask the clerk to correct the stock) I'm using php+MySql. But this is more a logical problem than a programing one

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  • Boost Python : How to only expose the constructor of a class with virtual (pure & impure) methods

    - by fallino
    Hello, I'm a newbie with Boost::Python but I tried to search on the web to do so I want to expose a 3rd party library to Python. One of the class of the library (.hpp) is composed of a public constructor with arguments a protected constructor and functions various regular functions various pure virtual functions various non pure virtual functions First, I did not succeed in building it without having errors about this protected constructor. I finally commented it. A first question would be : Is there a way to exclude these protected functions since I don't want to expose them ? (I know it's possible and easy with Py++, but I started without using it) Then I tried to expose all of my functions, beginning with the pure virtual ones (commenting them all except one), which wasn't a success too So I finally decided not to expose these virtual functions (which in fact seems logical...), but, here again, I didn't manage building it with a simple constructor with arguments (without no_init). So my second question is : Is there a way to exclude these virtual functions since I don't want to expose them ? Sorry if it seems trivial but I didn't find anything explicit on the web and I need something rather explicit :). Thanks in advance

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  • Having trouble setting up API call using array of parameters

    - by Josh
    I am building a class to send API calls to Rapidshare and return the results of said call. Here's how I want the call to be done: $rs = new rs(); $params = array( 'sub' => 'listfiles_v1', 'type' => 'prem', 'login' => '10347455', 'password' => 'not_real_pass', 'realfolder' => '0', 'fields' => 'filename,downloads,size', ); print_r($rs->apiCall($params)); And here's the class so far: class RS { var $baseUrl = 'http://api.rapidshare.com/cgi-bin/rsapi.cgi?sub='; function apiCall($params) { $newUrl = $baseUrl; $keys = array_keys($params); $count = count($params); for($i = 0; $i < $count; $i++) { $newUrl .= $keys[$i]; $newUrl .= '&'; $newUrl .= $params[$keys[$i]]; } return $newUrl; } } Obviously i'm returning $newUrl and using print_r() to test the query string, and this is what it comes out as with the code shown above: sub&listfiles_v1type&premlogin&10347455password&_not_real_passrealfolder&0fields&filename,downloads,size When it should be: http://api.rapidshare.com/cgi-bin/rsapi.cgi?sub=listfiles_v1&type=prem&login=10347455&password=not_real_pass&realfolder=0&fields=filename,downloads,size Hopefully you can see what I'm trying to do here :P It's probably a silly mistake that I'm failing to find or a logical error. Thanks in advance.

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  • Data sharing amongst JPA Entities

    - by Nick
    Setup: I have a simple web app that has a handfull of forms, each on a separate page. These forms represent patient data. There is a one-to-one relationship between patient and all these forms/entities. Each form maps directly to a db table and a JPA entity, maybe not the best architecture but it works and is simple. Question: If form/entity A and form/entity B share a common chunk of data (one of more fields), what is the best way to handle that in JPA. I.E. - If the data gets inserted via form A, I need it to show up in form B as existing data and vice versa. In other words its logical for both entities to contain that data. I believe I will have to move the common data into its own entity and define the relationships that way, but I have tried many different ways and none gets me all the way, at least with basic JPA. Can this be done through pure JPA relationships or will I have to write a bunch of code to make this happen manually. Not looking for code specifically, just the correct way to model this data. Thanks.

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  • Submit information to url, but also open PDF

    - by Mad Ducky Digital Branding
    I have a client whose desire is to have her Wordpress blog show a MailChimp form on her home page as a gateway to a .pdf. I need the following behavior to occur when the user clicks "Submit": execute the included MailChimp's javascript file; this ensures the form was properly filled, and then performs the sign-up to the newsletter list (don't need help with this part) then show the user an informational PDF for download or viewing EDIT: The logical order was flipped from when I originally posted this. The script should execute, and only if the script gets executed properly should the PDF show to the user Note: My experience level with HTML and PHP is 3/4, and with JS I am 2/4 EDIT: (seems more like 1/4 at this point lol). If my research is correct, PHP (server-side language) would be used to do that which the client wants. Additional validation is not necessary beyond what MailChimp's script provides (it ensures that user has submitted a completed form) is not necessary in this case (the client says it's ok if the e-mail isn't valid at all). EDIT: Reworded this sentence from original post to be more clear The .pdf URL and content is static, and simply needs to be shown, not generated. ----RESEARCH---- I know that the Mailchimp form uses the following line to actually submit the information, but I want to do the action mentioned below, as well as open the aforementioned .pdf: <form action="http://*BLAH*.us2.list-manage.com/subscribe/post?u=*BLAHBLAH*&amp;id=*BLAHBLAHBLAH*" method="post" id="mc-embedded-subscribe-form" name="mc-embedded-subscribe-form" class="validate" target="_blank"> I am reading on other sites that I can conceivably point "action" to a .php file, but if there is a way to do this with javascript - since its using the .js file that I created for that already anyways, then I would be most happy. Barring that, I'll take what I can get.. ----SOLUTION?---- ...

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  • Surprising results with .NET multi-theading algorithm

    - by Myles J
    Hi, I've recently wrote a C# console time tabling algorithm that is based on a combination of a genetic algorithm with a few brute force routines thrown in. The initial results were promising but I figured I could improve the performance by splitting the brute force routines up to run in parallel on multi processor architectures. To do this I used the well documented Producer/Consumer model (as documented in this fantastic article http://www.albahari.com/threading/part2.aspx#_ProducerConsumerQWaitHandle). I changed my code to create one thread per logical processor during the brute force routines. The performance gains on my work station were very pleasing. I am running Windows XP on the following hardware: Intel Core 2 Quad CPU 2.33 GHz 3.49 GB RAM Initial tests indicated average performance gains of approx 40% when using 4 threads. The next step was to deploy the new multi-threading version of the algorithm to our higher spec UAT server. Here is the spec of our UAT server: Windows 2003 Server R2 Enterprise x64 8 cpu (Quad-Core) AMD Opteron 2.70 GHz 255 GB RAM After running the first round of tests we were all extremely surprised to find that the algorithm actually runs slower on the high spec W2003 server than on my local XP work station! In fact the tests seem to indicate that it doesn't matter how many threads are generated (tests were ran with the app spawning between 2 to 32 threads). The algorithm always runs significantly slower on the UAT W2003 server? How could this be? Surely the app should run faster on a 8 cpu (Quad-Core) than my 2 Quad work station? Why are we seeing no performance gains with the multi-threading on the W2003 server whilst the XP workstation tests show gains of up to 40%? Any help or pointers would be appreciated. Regards Myles

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  • Stock management of assemblies and its sub parts

    - by The Disintegrator
    I have to track the stock of individual parts and kits (assemblies) and can't find a satisfactory way of doing this. Sample bogus and hyper simplified database: Table prod: prodID 1 prodName Flux capacitor prodCost 900 prodPrice 1350 (900*1.5) prodStock 3 - prodID 2 prodName Mr Fusion prodCost 300 prodPrice 600 (300*2) prodStock 2 - prodID 3 prodName Time travel kit prodCost 1650 (1350+300) prodPrice 2145 (1650*1.3) prodStock 2 Table rels relID 1 relSrc 1 (Flux capacitor) relType 4 (is a subpart of) relDst 3 (Time travel kit) - relID 2 relSrc 2 (Mr Fusion) relType 4 (is a subpart of) relDst 3 (Time travel kit) prodPrice: it's calculated based on the cost but not in a linear way. In this example for costs of 500 or less, the markup is a 200%. For costs of 500-1000 the markup is 150%. For costs of 1000+ the markup is 130% That's why the time travel kit is much cheaper than the individual parts prodStock: here is my problem. I can sell kits or the individual parts, So the stock of the kits is virtual. The problem when I buy: Some providers sell me the Time Travel kit as a whole (with one barcode) and some sells me the individual parts (with a different barcode) So when I load the stock I don't know how to impute it. The problem when I sell: If I only sell kits, calculate the stock would be easy: "I have 3 Flux capacitors and 2 Mr Fusions, so I have 2 Time travel kits and a Flux Capacitor" But I can sell Kits or individual parts. So, I have to track the stock of the individual parts and the possible kits at the same time (and I have to compensate for the sell price) Probably this is really simple, but I can't see a simple solution. Resuming: I have to find a way of tracking the stock and the database/program is the one who has to do it (I cant ask the clerk to correct the stock) I'm using php+MySql. But this is more a logical problem than a programing one

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  • Class/Model Level Validation (as opposed to Property Level)? (ASP.NET MVC 2.0)

    - by Erx_VB.NExT.Coder
    Basically, what the title says. I have several properties that combine together to really make one logical answer, and i would like to run a server-side validation code (that i write) which take these multiple fields into account and hook up to only one validation output/error message that users see on the webpage. I looked at scott guthries method of extending an attribute and using it in yoru dataannotations declarations, but, as i can see, there is no way to declare a dataannotations-style attribute on multiple properties, and you can only place the declarations (such as [Email], [Range], [Required]) over one property :(. i have looked at the PropertiesMustMatchAttribute in the default mvc 2.0 project that appears when you start a new project, this example is as useful as using a pair of pins to check your motor oil - useless! i have tried this method, however, creating a class level attribute, and have no idea how to display the error from this in my aspx page. i have tried html.ValidationMessage("ClassNameWhereAttributeIsAdded") and a variety of other thing, and it has not worked. and i should mention, there is NOT ONE blog post on doing validation at this level - despite this being a common need in any project or business logic scenario! can anyone help me in having my message displayed in my aspx page, and also if possible a proper document or reference explaining validation at this level?

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  • python: how to design a container with elements that must reference their container

    - by Luke404
    (the title is admittedly not that great. Please forgive my English, this is the best I could think of) I'm writing a python script that will manage email domains and their accounts, and I'm also a newby at OOP design. My two (related?) issues are: the Domain class must do special work to add and remove accounts, like adding/removing them to the underlying implementation how to manage operations on accounts that must go through their container To solve the former issue I'd add a factory method to the Domain class that'll build an Account instance in that domain, and a 'remove' (anti-factory?) method to handle deletions. For the latter this seems to me "anti-oop" since what would logically be an operation on an Account (eg, change password) must always reference the containing Domain. Seems to me that I must add to the Account a reference back to the Domain and use that to get data (like the domain name) or call methods on the Domain class. Code example (element uses data from the container) that manages an underlying Vpopmail system: class Account: def __init__(self, name, password, domain): self.name = name self.password = password self.domain = domain def set_password(self, password): os.system('vpasswd %s@%s %s' % (self.name, self.domain.name, password) self.password = password class Domain: def __init__(self, domain_name): self.name = domain_name self.accounts = {} def create_account(self, name, password): os.system('vadduser %s@%s %s' % (name, self.name, password)) account = Account(name, password, self) self.accounts[name] = account def delete_account(self, name): os.system('vdeluser %s@%s' % (name, self.name)) del self.accounts[name] another option would be for Account.set_password to call a Domain method that would do the actual work - sounds equally ugly to me. Also note the duplication of data (account name also as dict key), it sounds logical (account names are "primary key" inside a domain) but accounts need to know their own name.

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  • CLR Stored Procedures

    - by Paul Hatcherian
    In an ASP.NET application, I have a small number of fairly complex, frequently used operations to execute against a database. In these operations, one or more of several tables needs updates or inserts based a logical evaluation of both input parameters and values of certain tables. I've maintained a separation of logic and data access, so the operation currently looks like this: Request received from client Business layer invokes data layer to retrieve data from database Business layer processes result and determines which operation to execute Business layer invokes appropriate data operation Response sent to client As you can see, the client is kept waiting while two separate requests are made to the database. In searching for a solution to this, I've found CLR Stored Procedures, but I'm not sure if I have the right idea about what they are useful for. I have written a replacement for the code above which especially places steps 2-4 in a CLR SP. My understanding is that the SP will be executed locally by SQL Server and result in only one call being made to the server. My initial benchmark tests show this is actually orders of magnitude slower than my original code, but I attribute that recompilation of the code I have not worked out yet and/or some flaw in my environment. My question is basically, is this the intended use of CLR SPs or am I missing something? I realize this is a bit of a compromise structurally, so if there's a better way to do it I'd love to hear it.

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  • What are the most interesting equivalences arising from the Curry-Howard Isomorphism?

    - by Tom
    I came upon the Curry-Howard Isomorphism relatively late in my programming life, and perhaps this contributes to my being utterly fascinated by it. It implies that for every programming concept there exists a precise analogue in formal logic, and vice versa. Here's an "obvious" list of such analogies, off the top of my head: program/definition | proof type/declaration | proposition inhabited type | theorem function | implication function argument | hypothesis/antecedent function result | conclusion/consequent function application | modus ponens recursion | induction identity function | tautology non-terminating function | absurdity tuple | conjunction (and) disjoint union | exclusive disjunction (xor) parametric polymorphism | universal quantification So, to my question: what are some of the more interesting/obscure implications of this isomorphism? I'm no logician so I'm sure I've only scratched the surface with this list. For example, here are some programming notions for which I'm unaware of pithy names in logic: currying | "((a & b) => c) iff (a => (b => c))" scope | "known theory + hypotheses" And here are some logical concepts which I haven't quite pinned down in programming terms: primitive type? | axiom set of valid programs? | theory ? | disjunction (or)

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  • Stock management of assemblies and its sub parts (relations)

    - by The Disintegrator
    I have to track the stock of individual parts and kits (assemblies) and can't find a satisfactory way of doing this. Sample bogus and hyper simplified database: Table prod: prodID 1 prodName Flux capacitor prodCost 900 prodPrice 1350 (900*1.5) prodStock 3 - prodID 2 prodName Mr Fusion prodCost 300 prodPrice 600 (300*2) prodStock 2 - prodID 3 prodName Time travel kit prodCost 1650 (1350+300) prodPrice 2145 (1650*1.3) prodStock 2 Table rels relID 1 relSrc 1 (Flux capacitor) relType 4 (is a subpart of) relDst 3 (Time travel kit) - relID 2 relSrc 2 (Mr Fusion) relType 4 (is a subpart of) relDst 3 (Time travel kit) prodPrice: it's calculated based on the cost but not in a linear way. In this example for costs of 500 or less, the markup is a 200%. For costs of 500-1000 the markup is 150%. For costs of 1000+ the markup is 130% That's why the time travel kit is much cheaper than the individual parts prodStock: here is my problem. I can sell kits or the individual parts, So the stock of the kits is virtual. The problem when I buy: Some providers sell me the Time Travel kit as a whole (with one barcode) and some sells me the individual parts (with a different barcode) So when I load the stock I don't know how to impute it. The problem when I sell: If I only sell kits, calculate the stock would be easy: "I have 3 Flux capacitors and 2 Mr Fusions, so I have 2 Time travel kits and a Flux Capacitor" But I can sell Kits or individual parts. So, I have to track the stock of the individual parts and the possible kits at the same time (and I have to compensate for the sell price) Probably this is really simple, but I can't see a simple solution. Resuming: I have to find a way of tracking the stock and the database/program is the one who has to do it (I cant ask the clerk to correct the stock) I'm using php+MySql. But this is more a logical problem than a programing one

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  • PHP site keeps opening to blank page, no errors.

    - by gene
    First, the premises: PHP loaded on IIS6 on Win2003 STD R2 SP2, PHP_5213 using FastCGI, MySQL_5145. Customer sent me the site files, which I unzipped to C:\InetPub\wwwroot\<site root>, then I created a new site in IIS, pointed to <site root>, added test.php to the site files for testing and it works, but visiting index.php produces a blank page with no errors. The readme.txt file present makes reference to application.php and explains root folder var and sets it to a non-existent file. I don't know PHP syntax, but I tried several logical changes with zero results. At this point I'm not even sure if that is the problem anymore. With PHP, MySQL & site debugging have put in over 20 hours. Still confused, I have resorted to heavy drug use and purchased a small firearm, loaded with a single round (even this seemed to take an inordinate amount of time). I've given up all hope. Someone please help save a new server and/or old administrator.

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  • Counting the number of words in a text area

    - by user1320483
    Hello everyone my first question on stack overflow import javax.swing.*; import java.util.*; import java.awt.event.*; public class TI extends JFrame implements ActionListener { static int count=0; String ct; JTextField word; JTextArea tohide; public static void main(String arg[]) { TI ti=new TI(); } public TI() { JPanel j=new JPanel(); JLabel def=new JLabel("Enter the text to be encrypted"); word=new JTextField("",20); tohide=new JTextArea("",5,20); JButton jb=new JButton("COUNT"); tohide.setBorder(BorderFactory.createLoweredBevelBorder()); j.add(def); j.add(tohide); j.add(word); j.add(jb); add(j); setSize(500,500); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setLocationRelativeTo(null); jb.addActionListener(this); } public void actionPerformed(ActionEvent ae) { String txt=tohide.getText(); StringTokenizer stk=new StringTokenizer(txt," "); while(stk.hasMoreTokens()) { String token=stk.nextToken(); count++; } ct=Integer.toString(count);; word.setText(ct); } } I want to count the number of words that are being typed in the textarea.There is a logical error.As I keep clicking the count button the word count increases.

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  • Error while splitting application context file in spring

    - by Krupal
    I am trying to split the ApplicationContext file in Spring. For ex. the file is testproject-servlet.xml having all the entries. Now I want to split this single file into multiple files according to logical groups like : group1-services.xml, group2-services.xml I have created following entries in web.xml : <servlet> <servlet-name>testproject</servlet-name> <servlet-class> org.springframework.web.servlet.DispatcherServlet </servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value> /WEB-INF/group1-services.xml, /WEB-INF/group2-services.xml </param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> I am using SimpleUrlHandlerMapping as: RegisterController PayrollServicesController I also have the controller defined as : .. .. The problem is that I have splitted the ApplicationContext file "testproject-servlet.xml" into two different files and I have kept the above entries in "group1-services.xml". Is it fine? I want to group things logically based on their use in seperate .xml files. But I am getting the following error when I try to access a page inside the application : org.springframework.web.servlet.DispatcherServlet noHandlerFound WARNING: No mapping for [/TestProject/payroll_services.htm] in DispatcherServlet with name 'testproject' Please tell me how to resolve it. Thanks in Advance !

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  • My Website was hacked using Statcounter! Does Statcounter keep a record of cookies?

    - by Cyril Gupta
    I had a rather interesting case of hacking on my ASP.Net MVC website. For this website I had implemented a rather uncomplicated authentication system for my admin area -- an encrypted cookie which had an identifying signature for the member. Whenever the admin visits the website the cookie would be decrypted and signature verified. If matching he wouldn't have to sign in. Couple of days ago a visitor on my site told me that he was able to sign into my website simply by clicking no a referral link on his Statcounter console which pointed to my admin area (I had visited his site from a link inside my admin view). He just clicked on a link in statcounter and he was signed in as the admin! The only way this could have happened was if statcounter somehow recorded my cookies and used those when he clicked on the link pointing to my admin! Is that logical or fathomable? I don't understand what's going on. Do you have any suggestions as to how I can protect my website against things like this?

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