Search Results

Search found 4835 results on 194 pages for 'practice'.

Page 157/194 | < Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >

• how to create and track multiple pairs "View-ViewModel"?

  - by Gianluca Colucci

  Hi! I am building an application that is based on MVVM-Light. I am in the need of creating multiple instances of the same View, and each one should bind to its own ViewModel. The default ViewModelLocator implements ViewModels as singletons, therefore different instances of the same View will bind to the same ViewModel. I could create the ViewModel in the VMLocator as a non-static object (as simple as returning new VM()...), but that would only partially help me. In fact, I still need to keep track of the opened windows. Nevertheless, each window might open several other windows (of a different kind, though). In this situation I might need to execute some operation on the parent View and all its children. For example before closing the View P, I might want to close all its children (view C1, view C2, etc.). Hence, is there any simple and easy way to achieve this? Or is there any best practice you would advice me to follow? Thanks in advance for your precious help. Cheers, Gianluca.

  Read the article

• Best practices to develop and maintaing code for complex JQuery/JQueryUI based applications

  - by dafi

  I'm working on my first very complex JQuery based application. A single web page can contain hundreds of JQuery related code for example to JQueryUI dialogs. Now I want to organize code in separated files. For example I'm moving all initialization dialogs code $("#dialog-xxx").dialog({...}) in separated files and due to reuse I wrap them on single function call like dialogs.js function initDialog_1() { $("#dialog-1").dialog({}); } function initDialog_2() { $("#dialog-2").dialog({}); } This simplifies function code and make caller page clear $(function() { // do some init stuff initDialog_1(); initTooltip_2(); }); Is this the correct pattern? Are you using more efficient techniques? I know that splitting code in many js files introduces an ugly band-bandwidth usage so. Does exist some good practice or tool to 'join' files for production environments? I imagine some tool that does more work than simply minimize and/or compress JS code.

  Read the article

• ASP.NET Ajax - Asynch request has separate session???

  - by Marcus King

  We are writing a search application that saves the search criteria to session state and executes the search inside of an asp.net updatepanel. Sometimes when we execute multiple searches successively the 2nd or 3rd search will sometimes return results from the first set of search criteria. Example: our first search we do a look up on "John Smith" - John Smith results are displayed. The second search we do a look up on "Bob Jones" - John Smith results are displayed. We save all of the search criteria in session state as I said, and read it from session state inside of the ajax request to format the DB query. When we put break points in VS everything behaves as normal, but without them we get the original search criteria and results. My guess is because they are saved in session, that the ajax request somehow gets its own session and saves the criteria to that, and then retrieves the criteria from that session every time, but the non-async stuff is able to see when the criteria is modified and saves the changes to state accordingly, but because they are from two different sessions there is a disparity in what is saved and read. EDIT::: To elaborate more, there was a suggestion of appending the search criteria to the query string which normally is good practice and I agree thats how it should be but following our requirements I don't see it as being viable. They want it so the user fills out the input controls hits search and there is no page reload, the only thing they see is a progress indicator on the page, and they still have the ability to navigate and use other features on the current page. If I were to add criteria to the query string I would have to do another request causing the whole page to load, which depending on the search criteria can take a really long time. This is why we are using an ajax call to perform the search and why we aren't causing another full page request..... I hope this clarifies the situation.

  Read the article

• How should I define a composite foreign key for domain constraints in the presence of surrogate keys

  - by Samuel Danielson

  I am writing a new app with Rails so I have an id column on every table. What is the best practice for enforcing domain constraints using foreign keys? I'll outline my thoughts and frustration. Here's what I would imagine as "The Rails Way". It's what I started with. Companies: id: integer, serial company_code: char, unique, not null Invoices: id: integer, serial company_id: integer, not null Products: id: integer, serial sku: char, unique, not null company_id: integer, not null LineItems: id: integer, serial invoice_id: integer, not null, references Invoices (id) product_id: integer, not null, references Products (id) The problem with this is that a product from one company might appear on an invoice for a different company. I added a (company_id: integer, not null) to LineItems, sort of like I'd do if only using natural keys and serials, then added a composite foreign key. LineItems (product_id, company_id) references Products (id, company_id) LineItems (invoice_id, company_id) references Invoices (id, company_id) This properly constrains LineItems to a single company but it seems over-engineered and wrong. company_id in LineItems is extraneous because the surrogate foreign keys are already unique in the foreign table. Postgres requires that I add a unique index for the referenced attributes so I am creating a unique index on (id, company_id) in Products and Invoices, even though id is simply unique. The following table with natural keys and a serial invoice number would not have these issues. LineItems: company_code: char, not null sku: char, not null invoice_id: integer, not null I can ignore the surrogate keys in the LineItems table but this also seems wrong. Why make the database join on char when it has an integer already there to use? Also, doing it exactly like the above would require me to add company_code, a natural foreign key, to Products and Invoices. The compromise... LineItems: company_id: integer, not null sku: integer, not null invoice_id: integer, not null does not require natural foreign keys in other tables but it is still joining on char when there is a integer available. Is there a clean way to enforce domain constraints with foreign keys like God intended, but in the presence of surrogates, without turning the schema and indexes into a complicated mess?

  Read the article

• Should all public methods of an API be documented?

  - by cynicalman

  When writing "library" type classes, is it better practice to always write markup documentation (i.e. javadoc) in java or assume that the code can be "self-documenting"? For example, given the following method stub: /** * Copies all readable bytes from the provided input stream to the provided output * stream. The output stream will be flushed, but neither stream will be closed. * * @param inStream an InputStream from which to read bytes. * @param outStream an OutputStream to which to copy the read bytes. * @throws IOException if there are any errors reading or writing. */ public void copyStream(InputStream inStream, OutputStream outStream) throws IOException { // copy the stream } The javadoc seems to be self-evident, and noise that just needs to be updated if the funcion is changed at all. But the sentence about flushing and not closing the stream could be valuable. So, when writing a library, is it best to: a) always document b) document anything that isn't obvious c) never document (code should speak for itself!) I usually use b), myself (since the code can be self-documenting otherwise)...

  Read the article

• Unit Testing using InternalsVisibleToAttribute requires compiling with /out:filename.ext?

  - by Will Marcouiller

  In my most recent question: Unit Testing Best Practice? / C# InternalsVisibleTo() attribute for VBNET 2.0 while testing?, I was asking about InternalsVisibleToAttribute. I have read the documentation on how to use it, and everything is fine and understood. However, I can't instantiate my class Groupe from my Testing project. I want to be able to instantiate my internal class in my wrapper assembly, from my testing assembly. Any help is appreciated! EDIT #1 Here's the compile-time error I get when I do try to instantiate my type: Erreur 2 'Carra.Exemples.Blocs.ActiveDirectory.Groupe' n'est pas accessible dans ce contexte, car il est 'Private'. C:\Open\Projects\Exemples\Src\Carra.Exemples.Blocs.ActiveDirectory\Carra.Exemples.Blocs.ActiveDirectory.Tests\GroupeTests.vb 9 18 Carra.Exemples.Blocs.ActiveDirectory.Tests (This says that my type is not accessible in this context, because it is private.) But it's Friend (internal)! EDIT #2 Here's a piece of code as suggested for the Groupe class implementing the Public interface IGroupe: #Region "Importations" Imports System.DirectoryServices Imports System.Runtime.CompilerServices #End Region <Assembly: InternalsVisibleTo("Carra.Exemples.Blocs.ActiveDirectory.Tests")> Friend Class Groupe Implements IGroupe #Region "Membres privés" Private _classe As String = "group" Private _domaine As String Private _membres As CustomSet(Of IUtilisateur) Private _groupeNatif As DirectoryEntry #End Region #Region "Constructeurs" Friend Sub New() _membres = New CustomSet(Of IUtilisateur)() _groupeNatif = New DirectoryEntry() End Sub Friend Sub New(ByVal domaine As String) If (String.IsNullOrEmpty(domaine)) Then Throw New ArgumentNullException() _domaine = domaine _membres = New CustomSet(Of IUtilisateur)() _groupeNatif = New DirectoryEntry(domaine) End Sub Friend Sub New(ByVal groupeNatif As DirectoryEntry) _groupeNatif = groupeNatif _domaine = _groupeNatif.Path _membres = New CustomSet(Of IUtilisateur)() End Sub #End Region And the code trying to use it: #Region "Importations" Imports NUnit.Framework Imports Carra.Exemples.Blocs.ActiveDirectory.Tests #End Region <TestFixture()> _ Public Class GroupeTests <Test()> _ Public Sub CreerDefaut() Dim g As Groupe = New Groupe() Assert.IsNotNull(g) Assert.IsInstanceOf(Groupe, g) End Sub End Class EDIT #3 Damn! I have just noticed that I wasn't importing the assembly in my importation region. Nope, didn't solve anything =( Thanks!

  Read the article

• iPhone offline reading

  - by Andy

  Hi, first of all - I am quite new to iPhone App development (3 months). I am working for a software company that offers a content management system. Our customers are for the main part publishing houses for magazines. They use our software to write articles to their homepages. Now we want to offer iPhone Applications to go with our cms. What I have accomplished so far is an RSS reader that shows newly published articles in a list view. The user selects one article and is redirected to a specially formatted detail view of this article. The next step is to add offline reading capabilities. I have searched the internet up and down but couldn't find anything like a best practice for that. I get it that there are two possibilities in general: Store the contents of the uiwebview locally on the iPhone/iPad (including css, images, js and so on). There would be the need to rework the basic html to use the downloaded css, images and js. Also I would have to somehow edit hyperlinks to following pages in multipage articles - Sounds like a lot of work ;) Create a PDF on the server side and download that to the mobile device. Rework the RSS Source to point to the locally saved pdf instead of the website on the server. My question is - what is the better way to go? Are there any downsides for either of the possibilities? Are there other (simple ;)) ways to implement offline reading features? Are there possibly any howto's that I could've missed? Thanks y'all!

  Read the article

• .NET EventHandlers - Generic or no?

  - by Chris Marasti-Georg

  Every time I start in deep in a C# project, I end up with lots of events that really just need to pass a single item. I stick with the EventHandler/EventArgs practice, but what I like to do is have something like: public delegate void EventHandler<T>(object src, EventArgs<T> args); public class EventArgs<T>: EventArgs { private T item; public EventArgs(T item) { this.item = item; } public T Item { get { return item; } } } Later, I can have my public event EventHandler<Foo> FooChanged; public event EventHandler<Bar> BarChanged; However, it seems that the standard for .NET is to create a new delegate and EventArgs subclass for each type of event. Is there something wrong with my generic approach? EDIT: The reason for this post is that I just re-created this in a new project, and wanted to make sure it was ok. Actually, I was re-creating it as I posted. I found that there is a generic EventHandler<TEventArgs, so you don't need to create the generic delegate, but you still need the generic EventArgs<T class, because TEventArgs: EventArgs. Another EDIT: One downside (to me) of the built-in solution is the extra verbosity: public event EventHandler<EventArgs<Foo>> FooChanged; vs. public event EventHandler<Foo> FooChanged; It can be a pain for clients to register for your events though, because the System namespace is imported by default, so they have to manually seek out your namespace, even with a fancy tool like Resharper... Anyone have any ideas pertaining to that?

  Read the article

• Why doesn't every class in the .Net framework have a corresponding interface?

  - by Thorsten Lorenz

  Since I started to develop in a test/behavior driven style, I appreciated the ability to mock out every dependency. Since mocking frameworks like Moq work best when told to mock an interface, I now implement an interface for almost every class I create b/c most likely I will have to mock it out in a test eventually. Well, and programming to an interface is good practice, anyways. At times, my classes take dependencies on .Net classes (e.g. FileSystemWatcher, DispatcherTimer). It would be great in that case to have an interface, so I could depend on an IDispatcherTimer instead, to be able to pass it a mock and simulate its behavior to see if my system under test reacts correctly. Unfortunately both of above mentioned classes do not implement such interfaces, so I have to resort to creating adapters, that do nothing else but inherit from the original class and conform to an interface, that I then can use. Here is such an adapter for the DispatcherTimer and the corresponding interface: using System; using System.Windows.Threading; public interface IDispatcherTimer { #region Events event EventHandler Tick; #endregion #region Properties Dispatcher Dispatcher { get; } TimeSpan Interval { get; set; } bool IsEnabled { get; set; } object Tag { get; set; } #endregion #region Public Methods void Start(); void Stop(); #endregion } /// <summary> /// Adapts the DispatcherTimer class to implement the <see cref="IDispatcherTimer"/> interface. /// </summary> public class DispatcherTimerAdapter : DispatcherTimer, IDispatcherTimer { } Although this is not the end of the world, I wonder, why the .Net developers didn't take the minute to make their classes implement these interfaces from the get go. It puzzles me especially since now there is a big push for good practices from inside Microsoft. Does anyone have any (maybe inside) information why this contradiction exists?

  Read the article

• Are PyArg_ParseTuple() "s" format specifiers useful in Python 3.x C API?

  - by Craig McQueen

  I'm trying to write a Python C extension that processes byte strings, and I have something basically working for Python 2.x and Python 3.x. For the Python 2.x code, near the start of my function, I currently have a line: if (!PyArg_ParseTuple(args, "s#:in_bytes", &src_ptr, &src_len)) ... I notice that the s# format specifier accepts both Unicode strings and byte strings. I really just want it to accept byte strings and reject Unicode. For Python 2.x, this might be "good enough"--the standard hashlib seems to do the same, accepting Unicode as well as byte strings. However, Python 3.x is meant to clean up the Unicode/byte string mess and not let the two be interchangeable. So, I'm surprised to find that in Python 3.x, the s format specifiers for PyArg_ParseTuple() still seem to accept Unicode and provide a "default encoded string version" of the Unicode. This seems to go against the principles of Python 3.x, making the s format specifiers unusable in practice. Is my analysis correct, or am I missing something? Looking at the implementation for hashlib for Python 3.x (e.g. see md5module.c, function MD5_update() and its use of GET_BUFFER_VIEW_OR_ERROUT() macro) I see that it avoids the s format specifiers, and just takes a generic object (O specifier) and then does various explicit type checks using the GET_BUFFER_VIEW_OR_ERROUT() macro. Is this what we have to do?

  Read the article

• Using maven-release-plugin to tag and commit to non-origin

  - by Ali G

  When I do a release of my project, I want to share the source with a wider group of people than I normally do during development. The code is shared via a Git repository. To do this, I have used the following: remote public repository - released code is pushed here, every week or so (http://example.com/public) remote private repository - non-release code is pushed here, more than daily (http://example.com/private) In my local git repository, I have the following remotes defined: origin http://example.com/private public http://example.com/public I am currently trying to configure the maven-release-plugin to manage versioning of the builds, and to manage tagging and pushing of code to the public repository. In my pom.xml, I have listed the <scm/ as follows: <scm><connection>scm:git:http://example.com/public</connection></scm> (Removing this line will cause mvn release:prepare to fail) However, when calling mvn release:clean release:prepare release:perform Maven calls git push origin tagname rather than pushing to the URL specified in the POM. So the questions are: Best practice: Should I just be tagging and committing in my private repo (origin), and pushing to public manually? Can I make Maven push to the repository that I choose, rather than defaulting to origin? I felt this was implied by the requirement of the <connection/ element in <scm/.

  Read the article

• theoretical and practical matrix multiplication FLOP

  - by mjr

  I wrote traditional matrix multiplication in c++ and tried to measure and compare its theoretical and practical FLOP. As I know inner loop of MM has 2 operation therefore simple MM theoretical Flops is 2*n*n*n (2n^3) but in practice I get something like 4n^3 + number of operation which is 2 i.e. 6n^3 also if I just try to add up only one array a[i][j]++ practical flops then calculate like 3n^3 and not n^3 as you see again it is 2n^3 +1 operation and not 1 operation * n^3 . This is in case if I use 1D array in three nested loops as Matrix multiplication and compare flop, practical flop is the same (near) the theoretical flop and depend exactly as the number of operation in inner loop.I could not find the reason for this behaviour. what is the reason in both case? I know that theoretical flop is not the same as practical one because of some operations like load etc. system specification: Intel core2duo E4500 3700g memory L2 cache 2M x64 fedora 17 sample results: Matrix matrix multiplication 512*512 Real_time: 1.718368 Proc_time: 1.227672 Total flpops: 807,107,072 MFLOPS: 657.429016 Real_time: 3.608078 Proc_time: 3.042272 Total flpops: 807,024,448 MFLOPS: 265.270355 theoretical flop: 2*512*512*512=268,435,456 Practical flops= 6*512^3 =807,107,072 Using 1 dimensional array float d[size][size]:512 or any size for (int j = 0; j < size; ++j) { for (int k = 0; k < size; ++k) { d[k]=d[k]+e[k]+f[k]+g[k]+r; } } Real_time: 0.002288 Proc_time: 0.002260 Total flpops: 1,048,578 MFLOPS: 464.027161 theroretical flop: *4n^2=4*512^2=1,048,576* practical flop : 4n^2+overhead (other operation?)=1,048,578 3 loop version: Real_time: 1.282257 Proc_time: 1.155990 Total flpops: 536,872,000 MFLOPS: 464.426117 theoretical flop:4n^3 = 536,870,912 practical flop: *4n^3=4*512^3+overheads(other operation?)=536,872,000* thank you

  Read the article

• The woes of (sometimes) storing "date only" in datetimes

  - by Heinzi

  We have two fields from and to (of type datetime), where the user can store the begin time and the end time of a business trip, e.g.: From: 2010-04-14 09:00 To: 2010-04-16 16:30 So, the duration of the trip is 2 days and 7.5 hours. Often, the exact times are not known in advance, so the user enters the dates without a time: From: 2010-04-14 To: 2010-04-16 Internally, this is stored as 2010-04-14 00:00 and 2010-04-16 00:00, since that's what most modern class libraries (e.g. .net) and databases (e.g. SQL Server) do when you store a "date only" in a datetime structure. Usually, this makes perfect sense. However, when entering 2010-04-16 as the to date, the user clearly did not mean 2010-04-16 00:00. Instead, the user meant 2010-04-16 24:00, i.e., calculating the duration of the trip should output 3 days, not 2 days. I can think of a few (more or less ugly) workarounds for this problem (add "23:59" in the UI layer of the to field if the user did not enter a time component; add a special "dates are full days" Boolean field; store "2010-04-17 00:00" in the DB but display "2010-04-16 24:00" to the user if the time component is "00:00"; ...), all having advantages and disadvantages. Since I assume that this is a fairly common problem, I was wondering: Is there a "standard" best-practice way of solving it? If there isn't, have you experienced a similar requirement, how did you solve it and what were the pros/cons of that solution?

  Read the article

• H.264 / FLV best practices for HTML

  - by Steve Murch

  I run a website with about 700 videos (And no, it's not porn -- get your mind out of the gutter :-) ). The videos are currently in FLV format. We use the JWPlayer to render those videos. IIS6 hosted. Everything works just fine. As I understand it, H.264 (not FLV and likely not OGG) is the emerging preferred HTML5 video standard. Today, the iPad really only respects H.264 or YouTube. Presumably, soon many more important browsers will follow Apple's lead and respect only the HTML5 tag. OK, so I think I can figure out how to convert my existing videos into the proper H.264 format. There are various tools available, including ffmpeg.exe. I haven't tried it yet, but I don't think that's going to be a problem after fiddling with the codec settings. My question is more about the container itself -- that is, planning graceful transition for all users. What's the best-practice recommendation for rendering these videos? If I just use the HTML5 tag, then presumably any browser that doesn't yet support HTML5 won't see the videos. And if I render them in Flash format via the JWPlayer or some other player, then they won't be playable on the iPad. Do I have to do ugly UserAgent detection here to figure out what to render? I know the JWPlayer supports H.264 media, but isn't the player itself a Flash component and therefore not playable on the iPad? Sorry if I'm not being clear, but I'm scratching my head on a graceful transition plan that will work for current browsers, the iPad and the upcoming HTML5 wave. I'm not a video expert, so any advice would be most welcome, thanks.

  Read the article

• General Drools Question

  - by El Guapo

  For the last few months my company has been using a product from a company called Informatica (previously AgentLogic) called RulePoint. This product has proven itself very easy to use with a well-developed and easy-to-use SDK for customization. The way we use the product for CEP is fairly trivial, we have 2 sources which we monitor for our rule data, the first being a JMS Queue, the second being a Jabber IM account. The product runs on any java-based application server (WebLogic, Tomcat, etc) and runs just about flawlessly. Last week my boss says, "Hey, I've heard that we may be able to do the same thing we are doing with RulePoint with an open-source product called Drools. Check it out and let me know what you think." I've heard of people using Drools for flow-based operations (validation, etc), however, I've never heard of anyone using their CEP product (Fusion) in practice. So, being the diligent worker, I have undertaken this task. I've downloaded all the files (version 5.0) and accompanying documentation and have started to read. I've read through just about all the docs and run most of the examples, but I still don't really see HOW drools works for CEP. While there are examples for using Data (or Facts, I guess) from JMS, I don't see how this thing stays "running", continuously monitoring a queue until the application is actually stopped. RulePoint pretty must just sits and listens, however, Drools seems to not. I could probably write a full-blown command-line application for our needs, however, I was hoping to leverage some of the benefits of using a application server provides. I guess I'm looking for some good tutorials or an example of how someone is using Drools and CEP in production. Thanks in advanced for any information, advice you may be able to provide.

  Read the article

• Populating JavaScript Array from JSP List

  - by tkeE2036

  Ok so perhaps someone can help me with a problem I'm trying to solve. Essentially I have a JSP page which gets a list of Country objects (from the method referenceData() from a Spring Portlet SimpleFormController, not entirely relevant but just mentioning in case it is). Each Country object has a Set of province objects and each province and country have a name field: public class Country { private String name; private Set<Province> provinces; //Getters and setters } public class Province { private String name; //Getters and setters } Now I have two drop down menus in my JSP for countries and provinces and I want to filter the provinces by country. I've been following this tutorial/guide to make a chain select in JavaScript. Now I need a dynamic way to create the JavaScript array from my content. And before anyone mentions AJAX this is out of the question since our project uses portlets and we'd like to stay away from using frameworks like DWR or creating a servlet. Here is the JavaScript/JSP I have so far but it is not populating the Array with anything: var countries = new Array(); <c:forEach items="${countryList}" var="country" varStatus="status"> countries[status.index] = new Array(); countries[status.index]['country'] = ${country.name}; countries[status.index]['provinces'] = [ <c:forEach items="${country.provinces}" var="province" varStatus="provinceStatus"> '${province.name}' <c:if test="${!provinceStatus.last}"> , </c:if> </c:forEach> ]; </c:forEach> Does anyone know how to create an JavaScript array in JSP in the case above or what the 'best-practice' would be considered in this case? Thanks in advance!

  Read the article

• Linq Query Performance , comparing Compiled query vs Non-Compiled.

  - by AG.

  Hello Guys, I was wondering if i extract the common where clause query into a common expression would it make my query much faster, if i have say something like 10 linq queries on a collection with exact same 1st part of the where clause. I have done a small example to explain a bit more . public class Person { public string First { get; set; } public string Last { get; set; } public int Age { get; set; } public String Born { get; set; } public string Living { get; set; } } public sealed class PersonDetails : List<Person> { } PersonDetails d = new PersonDetails(); d.Add(new Person() {Age = 29, Born = "Timbuk Tu", First = "Joe", Last = "Bloggs", Living = "London"}); d.Add(new Person() { Age = 29, Born = "Timbuk Tu", First = "Foo", Last = "Bar", Living = "NewYork" }); Expression<Func<Person, bool>> exp = (a) => a.Age == 29; Func<Person, bool> commonQuery = exp.Compile(); var lx = from y in d where commonQuery.Invoke(y) && y.Living == "London" select y; var bx = from y in d where y.Age == 29 && y.Living == "NewYork" select y; Console.WriteLine("All Details {0}, {1}, {2}, {3}, {4}", lx.Single().Age, lx.Single().First , lx.Single().Last, lx.Single().Living, lx.Single().Born ); Console.WriteLine("All Details {0}, {1}, {2}, {3}, {4}", bx.Single().Age, bx.Single().First, bx.Single().Last, bx.Single().Living, bx.Single().Born); So can some of the guru's here give me some advice if it would be a good practice to write query like var lx = "Linq Expression " or var bx = "Linq Expression" ? Any inputs would be highly appreciated. Thanks, AG

  Read the article

• What Is The Proper Location For One-Offs In VCS Repos?

  - by Joe Clark

  I have recently started using Mercurial as our VCS. Over the years, I have used RCS, CVS, and - for the last 5 years - SVN. Back 13 years ago, when I primarily used CVS and RCS, large projects went into CVS and one-offs were edited in place on the specific server and stored in RCS. This worked well as the one-offs were usually specific to the server and the servers were backed up nightly. Jump forward a decade and a lot of the one-off scripts became less centralized - they might be needed on any server at some random time. This was also OK, because now I was a begrudging SVN user. Everything (except for docs) got dumped into one repo. Jump to 2010. Now I am using Mercurial and am putting large projects in their own repo again. But what to do with the one-offs? The options as I see them: A repo for each script. It seems a bit cluttered to create a repo for every one page script that might get ran once a year. RCS Not an option. There are many possible servers that might need a specific script. Continuing to use SVN just for one-offs. No. There no advantage I see over the next option. Create a repo in Mercurial named "one-offs". This seems the most workable. The last option seems the best to me - however; is there a best practice regarding this? You also might be wondering if these scripts are truly one-offs if they will be reused. Some of them may be reused 6 months or a year from now - some, never. However, nearly all of them involve several man-hours of work due to either complex logic or extensive error checking. Simply discarding them is not efficient.

  Read the article

• Product Catalog Schema design

  - by FlySwat

  I'm building a proof of concept schema for a product catalog to possibly replace a very aging and crufty one we use. In our business, we sell both physical materials and services (one time and reoccurring charges). The current catalog schema has each distinct category broken out into individual tables, while this is nicely normalized and performs well, it is fairly difficult to extend. Adding a new attribute to a particular product involves changing the table schema and backpopulating old data. An idea I've been toying with has been something along the line of a base set of entity tables in 3rd normal form, these will contain the facts that are common among ALL products. Then, I'd like to build an Attribute-Entity-Value schema that allows each entity type to be extended in a flexible way using just data and no schema changes. Finally, I'd like to denormalize this data model into materialized views for each individual entity type. This views are what the application would access. We also have many tables that contain business rules and compatibility rules. These would join against the base entity tables instead of the views. My big concerns here are: Performance - Attribute-Entity-Value schemas are flexible, but typically perform poorly, should I be concerned? More Performance - Denormalizing using materialized views may have some risks, I'm not positive on this yet. Complexity - While this schema is flexible and maintainable using just data, I worry that the complexity of the design might make future schema changes difficult. For those who have designed product catalogs for large scale enterprises, am I going down the totally wrong path? Is there any good best practice schema design reading available for product catalogs?

  Read the article

• operator<< overload,

  - by mr.low

  //using namespace std; using std::ifstream; using std::ofstream; using std::cout; class Dog { friend ostream& operator<< (ostream&, const Dog&); public: char* name; char* breed; char* gender; Dog(); ~Dog(); }; im trying to overload the << operator. I'm also trying to practice good coding. But my code wont compile unless i uncomment the using namespace std. i keep getting this error and i dont know. im using g++ compiler. Dog.h:20: error: ISO C++ forbids declaration of ‘ostream’ with no type Dog.h:20: error: ‘ostream’ is neither function nor member function; cannot be declared friend. if i add line using std::cout; then i get this error. Dog.h:21: error: ISO C++ forbids declaration of ‘ostream’ with no type. Can somebody tell me the correct way to overload the << operator with out using namespace std;

  Read the article

• how to better (inambiguaously) use the terms CAPTCHA and various types of interactions?

  - by vgv8

  I am working on survey of state-of-the-art and trends of spam prevention techniques. I observe that non-intrusive, transparent to visitor spam prevention techniques (like context-based filtering or honey traps) are frequently called non-captcha. Is it correct understanding of term CAPTCHA which is "type of challenge-response [ 2 ]test used in computing to ensure that the response is not generated by a compute" [ 1 ] and challenge-response does not seem to imply obligatory human involvement. So, which understanding (definition) of term and classification I'd better to stick with? How would I better call CAPTCHA without direct human interaction in order to avoid ambiguity and confusion of terms understnding? How would I better (succinctly and unambiguously) coin the term for captchas requiring human interaction but without typing into textbox? How would I better (succinctly and unambiguously) coin the terms to mark the difference between human interaction with images (playing, drag&dropping, rearranging, clicking with images) vs. just recognizing them (and then typing into a textbox the answer without interaction with images)? PS. The problem is that recognition of a wiggled word in an image or typing the answer to question is also interaction and when I start to use the terms "interaction", "interactive", "captcha", "protection", "non-captcha", "non-interactive", "static", "dynamic", "visible", "hidden" the terms overlap ambiguously with which another (especailly because the definitions or their actual practice of usage are vague or contradictive). [ 1 ] http://en.wikipedia.org/wiki/CAPTCHA

  Read the article

• How to draw line inside a scatter plot

  - by ruffy

  I can't believe that this is so complicated but I tried and googled for a while now. I just want to analyse my scatter plot with a few graphical features. For starters, I want to add simply a line. So, I have a few (4) points and like in this plot [1] I want to add a line to it. http://en.wikipedia.org/wiki/File:ROC_space-2.png [1] Now, this won't work. And frankly, the documentation-examples-gallery combo and content of matplotlib is a bad source for information. My code is based upon a simple scatter plot from the gallery: # definitions for the axes left, width = 0.1, 0.85 #0.65 bottom, height = 0.1, 0.85 #0.65 bottom_h = left_h = left+width+0.02 rect_scatter = [left, bottom, width, height] # start with a rectangular Figure fig = plt.figure(1, figsize=(8,8)) axScatter = plt.axes(rect_scatter) # the scatter plot: p1 = axScatter.scatter(x[0], y[0], c='blue', s = 70) p2 = axScatter.scatter(x[1], y[1], c='green', s = 70) p3 = axScatter.scatter(x[2], y[2], c='red', s = 70) p4 = axScatter.scatter(x[3], y[3], c='yellow', s = 70) p5 = axScatter.plot([1,2,3], "r--") plt.legend([p1, p2, p3, p4, p5], [names[0], names[1], names[2], names[3], "Random guess"], loc = 2) # now determine nice limits by hand: binwidth = 0.25 xymax = np.max( [np.max(np.fabs(x)), np.max(np.fabs(y))] ) lim = ( int(xymax/binwidth) + 1) * binwidth axScatter.set_xlim( (-lim, lim) ) axScatter.set_ylim( (-lim, lim) ) xText = axScatter.set_xlabel('FPR / Specificity') yText = axScatter.set_ylabel('TPR / Sensitivity') bins = np.arange(-lim, lim + binwidth, binwidth) plt.show() Everything works, except the p5 which is a line. Now how is this supposed to work? What's good practice here?

  Read the article

• Pros and cons of making database IDs consistent and "readable"

  - by gmale

  Question Is it a good rule of thumb for database IDs to be "meaningless?" Conversely, are there significant benefits from having IDs structured in a way where they can be recognized at a glance? What are the pros and cons? Background I just had a debate with my coworkers about the consistency of the IDs in our database. We have a data-driven application that leverages spring so that we rarely ever have to change code. That means, if there's a problem, a data change is usually the solution. My argument was that by making IDs consistent and readable, we save ourselves significant time and headaches, long term. Once the IDs are set, they don't have to change often and if done right, future changes won't be difficult. My coworkers position was that IDs should never matter. Encoding information into the ID violates DB design policies and keeping them orderly requires extra work that, "we don't have time for." I can't find anything online to support either position. So I'm turning to all the gurus here at SA! Example Imagine this simplified list of database records representing food in a grocery store, the first set represents data that has meaning encoded in the IDs, while the second does not: ID's with meaning: Type 1 Fruit 2 Veggie Product 101 Apple 102 Banana 103 Orange 201 Lettuce 202 Onion 203 Carrot Location 41 Aisle four top shelf 42 Aisle four bottom shelf 51 Aisle five top shelf 52 Aisle five bottom shelf ProductLocation 10141 Apple on aisle four top shelf 10241 Banana on aisle four top shelf //just by reading the ids, it's easy to recongnize that these are both Fruit on Aisle 4 ID's without meaning: Type 1 Fruit 2 Veggie Product 1 Apple 2 Banana 3 Orange 4 Lettuce 5 Onion 6 Carrot Location 1 Aisle four top shelf 2 Aisle four bottom shelf 3 Aisle five top shelf 4 Aisle five bottom shelf ProductLocation 1 Apple on aisle four top shelf 2 Banana on aisle four top shelf //given the IDs, it's harder to see that these are both fruit on aisle 4 Summary What are the pros and cons of keeping IDs readable and consistent? Which approach do you generally prefer and why? Is there an accepted industry best-practice?

  Read the article

• Ways std::stringstream can set fail/bad bit?

  - by Evan Teran

  A common piece of code I use for simple string splitting looks like this: inline std::vector<std::string> split(const std::string &s, char delim) { std::vector<std::string> elems; std::stringstream ss(s); std::string item; while(std::getline(ss, item, delim)) { elems.push_back(item); } return elems; } Someone mentioned that this will silently "swallow" errors occurring in std::getline. And of course I agree that's the case. But it occurred to me, what could possibly go wrong here in practice that I would need to worry about. basically it all boils down to this: inline std::vector<std::string> split(const std::string &s, char delim) { std::vector<std::string> elems; std::stringstream ss(s); std::string item; while(std::getline(ss, item, delim)) { elems.push_back(item); } if(ss.fail()) { // *** How did we get here!? *** } return elems; } A stringstream is backed by a string, so we don't have to worry about any of the issues associated with reading from a file. There is no type conversion going on here since getline simply reads until it sees a newline or EOF. So we can't get any of the errors that something like boost::lexical_cast has to worry about. I simply can't think of something besides failing to allocate enough memory that could go wrong, but that'll just throw a std::bad_alloc well before the std::getline even takes place. What am I missing?

  Read the article

• iPhone Objective-C service handlers

  - by Xavi Colomer

  Hello community! I am a as3 developer, I am used to use handlers everytime I launch an event and I am wondering which is the best way / practice to do that in Objective C. Let's say I want to call a diferent services from my backend. In as3 would be something like this to listent to the finish event: service.addEventListener( Event.COMPLETE, handler_serviceDidFinished ) service2.addEventListener( Event.COMPLETE, handler_serviceDidFinished2 ) But how can I do the same in Objective C? The problem is I already created the protocols and delegates, but how can I separate each response from the server? For example: -(void)callService:( NSString * )methodName withParameters:(NSMutableDictionary *) parameters { ... if (self.delegate != NULL && [self.delegate respondsToSelector:@selector(serviceDidFinishSuccessfully:)]) { [delegate serviceDidFinishSuccessfully:data]; } } Well I'm trying to create a generic delegate here, so how can I separate each response for every service? My first idea is that maybe I should return the name of the service method in the delegate call to identify each service. Maybe I should create a UID for each service and pass it the same way... Any idea?

  Read the article

< Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >