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• sIFR3: controlling a and a:hover styles inside replaced through CSS rather than JS

  - by sneeuwitje

  For graceful degrading and minimal coding for the sIFR feature on my websites I would want to define styles in CSS as much as possible. Here's what I do: Define a H3 tag to be replaced by sIFR3. H3 comes in varying colors by CSS depending on it's container, say body.blue-txt h3{ color: #009CDA; } body.white-txt h3{ color: #FFFFFF; } body.etc... H3 might contain an anchor (I'm aware of semantical issues, but that's just how it is ... sorry) With setting sIFR.useStyleCheck = true; sIFR3 will show replaced normal H3 text with correct color, but when it contains a link, it shows the Flash default #0000FF .... All fine; I can tweak e.g. blue text in sifr-config.js by using the css-parameter for sIFR.replace(): sIFR.replace(futura, { selector: 'body.blue-txt h3', css: 'a {color: #009CDA; }, a:hover { color: #009CDA; text-decoration: underline; }' }); But that would have to be coded for every single text-color in my sIFR replacements in both JS and CSS. So I would want to make the sIFR.useStyleCheck setting just respect the CSS in sifr-config.css like: body.blue-txt h3{ color: #009CDA; } body.blue-txt h3 a{ color: #009CDA; } body.blue-txt h3 a:hover{ color: #009CDA; text-decoration: underline; } Only this doesn't seem to work ... the link text keeps popping up as #0000FF and the hover is not underlined. Is this just Not A Feature (Yet), or am doing something wrong?

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• MVC and repository pattern data efficiency

  - by Shawn Mclean

  My project is structured as follows: DAL public IQueryable<Post> GetPosts() { var posts = from p in context.Post select p; return posts; } Service public IList<Post> GetPosts() { var posts = repository.GetPosts().ToList(); return posts; } //Returns a list of the latest feeds, restricted by the count. public IList<PostFeed> GetPostFeeds(int latestCount) { List<Post> post - GetPosts(); //CODE TO CREATE FEEDS HERE return feeds; } Lets say the GetPostFeeds(5) is supposed to return the 5 latest feeds. By going up the list, doesn't it pull down every single post from the database from GetPosts(), just to extract 5 from it? If each post is say 5kb from the database, and there is 1 million records. Wont that be 5GB of ram being used per call to GetPostFeeds()? Is this the way it happens? Should I go back to my DAL and write queries that return only what I need?

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• Will fixed-point arithmetic be worth my trouble?

  - by Thomas

  I'm working on a fluid dynamics Navier-Stokes solver that should run in real time. Hence, performance is important. Right now, I'm looking at a number of tight loops that each account for a significant fraction of the execution time: there is no single bottleneck. Most of these loops do some floating-point arithmetic, but there's a lot of branching in between. The floating-point operations are mostly limited to additions, subtractions, multiplications, divisions and comparisons. All this is done using 32-bit floats. My target platform is x86 with at least SSE1 instructions. (I've verified in the assembler output that the compiler indeed generates SSE instructions.) Most of the floating-point values that I'm working with have a reasonably small upper bound, and precision for near-zero values isn't very important. So the thought occurred to me: maybe switching to fixed-point arithmetic could speed things up? I know the only way to be really sure is to measure it, that might take days, so I'd like to know the odds of success beforehand. Fixed-point was all the rage back in the days of Doom, but I'm not sure where it stands anno 2010. Considering how much silicon is nowadays pumped into floating-point performance, is there a chance that fixed-point arithmetic will still give me a significant speed boost? Does anyone have any real-world experience that may apply to my situation?

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• java distributed cache for low latency, high availability

  - by Shahbaz

  I've never used distributed caches/DHTs like memcached, jboss cache, ehcache, etc. I'm wondering which, if any, is appropriate for my use. First, I'm not doing web applications (as most of these project seem to be geared towards web apps). I write servers (Order Management Systems actually) for financial trading firms. The servers themselves are not too complicated. They need to receive information (market data, orders, executions, etc.) rout them to their destination while possibly transforming some of these messages. I am looking at these products to solve the following problems: * Safe repository of the state of the server. I'd rather build the logic of my application as a bunch of transformers (similar to Apache Camel) and store the state in a 'safe' place * This repository should be distributed: in case one of these data stores crashes, one or two more should be up and I should be able to switch to them seamlessly * This repository should be fast. Single digits milliseconds count here, in other words, systems which consume/process this data are automated systems, not humans clicking on links. This system needs to have high-throughput and low latency. By sending my data outside the process, I am necessarily slowing performance, but I am trying to balance absolute raw speed and absolute protection of data. * This repository should be safe. Similar to the point about several on-line backups, this system needs to write data to disk (potentially more than one disk). I'd really like to stop writing my own 'transaction servers.' Am I correct to be looking into projects such as jboss cache, ehcache, etc.? Thanks

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• UCMA 3.0 How to build a list of recipients and then broadcast an IM call to those recipients

  - by ficuscr

  I am developing an application using UCMA 3.0 that will run as a service and send out periodic 'broadcasts' in the form of Instant Message calls. I have been using the book "Professional Unified Communications Development with Microsoft Lync Server 2010" and have everything provisioned fine and am able to establish an application endpoint. I am stuck on two aspects though. 1) How to get a list of all users of Lync? Everything the UCMA can do is centered on a single user. For example it allows me to retrieve all contacts/groups present on a given users 'contact list' but does not provide any means to query for a list of available contacts that could be added to one of those contact lists. On the MSDN forum I found this post which leads me to think my best bet is simply to query AD directly. 2) What is the best way to actually send a broadcast style IM? My working premise is to attempt something like what I've found in this code example (specifically the public void SendIM() method). So, get a list of recipients from AD, (looping on each on to check current presence?), and then use Automation to make the IM call for each recipient in the collection. Does that make sense? Do I need to check presence of the recipient or do I just optimistically make the IM calls irregardless of their current presence status? Can anyone point me to some working code demonstrating sending an IM broadcast? You would think this is probably one of the most common use cases however the SDK samples do not cover it. Thanks in advance.

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• Static Data Structures on Embedded Devices (Android in particular)

  - by Mark

  I've started working on some Android applications and have a question regarding how people normally deal with situations where you have a static data set and have an application where that data is needed in memory as one of the standard java collections or as an array. In my current specific issue i have a spreadsheet with some pre-calculated data. It consists of ~100 rows and 3 columns. 1 Column is a string, 1 column is a float, 1 column is an integer. I need access to this data as an array in java. It seems like i could: 1) Encode in XML - This would be cpu intensive to decode in my experience. 2) build into SQLite database - seems like a lot of overhead for static access to data i only need array style access to in ram. 3) Build into binary blob and read in. (never done this in java, i miss void *) 4) Build a python script to take the CSV version of my data and spit out a java function that adds the values to my desired structure with hard coded values. 5) Store a string array via androids resource mechanism and compute the other 2 columns on application load. In my case the computation would require a lot of calls to Math.log, Math.pow and Math.floor which i'd rather not have to do for load time and battery usage reasons. I mostly work in low power embedded applications in C and as such #4 is what i'm used to doing in these situations. It just seems like it should be far easier to gain access to static data structures in java/android. Perhaps I'm just being too battery usage conscious and in my single case i imagine the answer is that it doesn't matter much, but if every application took that stance it could begin to matter. What approaches do people usually take in this situation? Anything I missed?

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• How can I turn a column name into a result value in SQL Server?

  - by Brennan

  I have a table which has essentially boolean values in a legacy database. The column names are stored as string values in another table so I need to match the column names of one table to a string value in another table. I know there has to be a way to do this directly with SQL in SQL Server but it is beyond me. My initial thought was to use PIVOT but it is not enabled by default and enabling it would likely be a difficult process with pushing that change to the Production database. I would prefer to use what is enabled by default. I am considering using COALESCE to translate the boolean value to the string that value that I need. This will be a manual process. I think I will also use a table variable to insert the results of the first query into that variable and use those results to do the second query. I still have the problem that the columns are on a single row so I wish I could easily pivot the values to put the column names in the result set as strings. But if I could easily do that I could easily write the query with a sub-select. Any tips are welcome.

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• Searching a list of tuples in python

  - by Niclas Nilsson

  I'm having a database (sqlite) of members of an organisation (less then 200 people). Now I'm trying to write an wx app that will search the database and return some contact information in a wx.grid. The app will have 2 TextCtrls, one for the first name and one for the last name. What I want to do here is make it possible to only write one or a few letters in the textctrls and that will start to return result. So, if I search "John Smith" I write "Jo" in the first TextCtrl and that will return every single John (or any one else having a name starting with those letters). It will not have an "search"-button, instead it will start searching whenever I press a key. One way to solve this would be to search the database with like " SELECT * FROM contactlistview WHERE forname LIKE 'Jo%' " But that seems like a bad idea (very database heavy to do that for every keystroke?). Instead i thought of use fetchall() on a query like this " SELECT * FROM contactlistview " and then, for every keystroke, search the list of tuples that the query have returned. And that is my problem: Searching a list is not that difficult but how can I search a list of tuples with wildcards?

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• When using Data Annotations with MVC, Pro and Cons of using an interface vs. a MetadataType

  - by SkippyFire

  If you read this article on Validation with the Data Annotation Validators, it shows that you can use the MetadataType attribute to add validation attributes to properties on partial classes. You use this when working with ORMs like LINQ to SQL, Entity Framework, or Subsonic. Then you can use the "automagic" client and server side validation. It plays very nicely with MVC. However, a colleague of mine used an interface to accomplish exactly the same result. it looks almost exactly the same, and functionally accomplishes the same thing. So instead of doing this: [MetadataType(typeof(MovieMetaData))] public partial class Movie { } public class MovieMetaData { [Required] public object Title { get; set; } [Required] [StringLength(5)] public object Director { get; set; } [DisplayName("Date Released")] [Required] public object DateReleased { get; set; } } He did this: public partial class Movie :IMovie { } public interface IMovie { [Required] object Title { get; set; } [Required] [StringLength(5)] object Director { get; set; } [DisplayName("Date Released")] [Required] object DateReleased { get; set; } } So my question is, when does this difference actually matter? My thoughts are that interfaces tend to be more "reusable", and that making one for just a single class doesn't make that much sense. You could also argue that you could design your classes and interfaces in a way that allows you to use interfaces on multiple objects, but I feel like that is trying to fit your models into something else, when they should really stand on their own. What do you think?

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• Parent Control Mouse Enter/Leave Events With Child Controls

  - by Paul Williams

  I have a C# .NET 2.0 WinForms app. My app has a control that is a container for two child controls: a label, and some kind of edit control. You can think of it like this, where the outer box is the parent control: +---------------------------------+ | [Label Control] [Edit Control] | +---------------------------------+ I am trying to do something when the mouse enters or leaves the parent control, but I don't care if the mouse moves into one of its children. I want a single flag to represent "the mouse is somewhere inside the parent or children" and "the mouse has moved outside of the parent control bounds". I've tried handling MouseEnter and MouseLeave on the parent and both child controls, but this means the action begins and ends multiple times as the mouse moves across the control. In other words, I get this: Parent.OnMouseEnter (start doing something) Parent.OnMouseLeave (stop) Child.OnMouseEnter (start doing something) Child.OnMouseLeave (stop) Parent.OnMouseEnter (start doing something) Parent.OnMouseLeave (stop) The intermediate OnMouseLeave events cause some undesired effects as whatever I'm doing gets started and then stopped. I want to avoid that. I don't want to capture the mouse as the parent gets the mouse over, because the child controls need their mouse events, and I want menu and other shortcut keys to work. Is there a way to do this inside the .NET framework? Or do I need to use a Windows mouse hook?

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• Joining on a common table, how do you get a FULL OUTER JOIN to expand on another table?

  - by stimpy77

  I've scoured StackOverflow and Google for an answer to this problem. I'm trying to create a Microsot SQL Server 2008 view. Not a stored procedure. Not a function. Just a query (i.e. a view). I have three tables. The first table defines a common key, let's say "CompanyID". The other two tables have a sometimes-common field, let's say "EmployeeName". I want a single table result that, when my WHERE clause says "WHERE CompanyID = 12" looks like this: CompanyID | TableA | TableB 12 | John Doe | John Doe 12 | Betty Sue | NULL 12 | NULL | Billy Bob I've tried a FULL OUTER JOIN that looks like this: SELECT Company.CompanyID, TableA.EmployeeName, TableB.EmployeeName FROM Company FULL OUTER JOIN TableA ON Company.CompanyID = TableA.CompanyID FULL OUTER JOIN TableB ON Company.CompanyID = TableB.CompanyID AND (TableA.EmployeeName IS NULL OR TableB.EmployeeName IS NULL OR TableB.EmployeeName = TableA.EmployeeName) I'm only getting the NULL from one matched table, I'm not getting the expansion for the other table. In the above sample, I'm basically only getting the first and third rows and not the second. Can someone help me create this query and show me how this is done correctly? BTW I already have a stored procedure that looks very clean and populates an in-memory table, but that isn't what I want. Thanks.

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• Reference for proper handling of PID file on Unix

  - by bignose

  Where can I find a well-respected reference that details the proper handling of PID files on Unix? On Unix operating systems, it is common practice to “lock” a program (often a daemon) by use of a special lock file: the PID file. This is a file in a predictable location, often ‘/var/run/foo.pid’. The program is supposed to check when it starts up whether the PID file exists and, if the file does exist, exit with an error. So it's a kind of advisory, collaborative locking mechanism. The file contains a single line of text, being the numeric process ID (hence the name “PID file”) of the process that currently holds the lock; this allows an easy way to automate sending a signal to the process that holds the lock. What I can't find is a good reference on expected or “best practice” behaviour for handling PID files. There are various nuances: how to actually lock the file (don't bother? use the kernel? what about platform incompatibilities?), handling stale locks (silently delete them? when to check?), when exactly to acquire and release the lock, and so forth. Where can I find a respected, most-authoritative reference (ideally on the level of W. Richard Stevens) for this small topic?

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• Specifying ASP.NET MVC attributes for auto-generated data models

  - by Lyubomyr Shaydariv

  Hello to everyone. I'm very new to ASP.NET MVC (as well as ASP.NET in general), and going to gain some knowledge for this technology, so I'm sorry I can ask some trivial questions. I have installed ASP.NET MVC 3 RC1 and I'm trying to do the following. Let's consider that I have a model that's completely auto-generated from a table using the "LINQ to SQL Classes" template in VS2010. The template generates 3 files (two .cs files and one .layout file respectively), and the generated partial class is expected to be used as an MVC model. Let's also consider, a single DB column, that's mapped into the model, may look like this: [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_Name", DbType = "VarChar(128)")] public string Name { get { return this._Name; } set { if ( (this._Name != value) ) { // ... generated stuff goes here } } } The ASP.NET MVC engine also provides a beautiful declarative way to specify some additional stuff, like RequiredAttribute, DisplayNameAttribute and other nice attributes. But since the mapped model is a purely auto-genereated model, I've realized that I should not change the model manually, and specify the fields like: [Required] [DisplayName("Project name")] [StringLength(128)] [global::System.Data.Linq.Mapping.ColumnAttribute(Storage = "_Name", DbType = "VarChar(128)")] public string Name { ... though this approach works perfectly... until I change the model in the DBML-designer removing the ASP.NET MVC attributes automatically. So, how do I specify ASP.NET MVC attributes for the DBML models and their fields safely? Thanks in advance, and Merry Christmas.

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• Converting from Latitude/Longitude to Cartesian Coordinates with a World File and map image.

  - by Heath

  I have a java applet that allows users to import a jpeg and world file from the local system. The user can then "click" draw lines on the image that was imported. Each endpoint of each line contains a set of X/Y and Lat/Long values. The XY is standard java coordinate space, the applet uses an affine transform calculation with the world file to determine the lat/long for every point on the canvas. I have a requirement that allows a user to type a distance into a text field and use the arrow key to draw a line in a certain direction (Up, Down, Left, Right) from a single selected point on the screen. I know how to determine the lat/long of a point given a source lat/long, distance, and bearing. So a user types "100" in the text field and presses the Right arrow key a line should be drawn 100 feet to the right from the currently selected point. My issue is I don't know how to convert the distance( which is in feet ) into the distance in pixels. This would then tell my where to plot the point.

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• Before data is entered, is there a way to make a grouped table graphic placeholder?

  - by Matt Winters

  I have a grouped table with 3 sections, each section with a title. The 1st and 3rd sections always have only 1 row of information so before any user data is entered, I just put some words like "Enter Data Here..." as placeholder text. This text is edited (replaced) by the user with their own actual data. No problem. The 2nd section however will contain several rows of information entered by user and I'd prefer not to enter placeholder data in row 0, having the user Edit the first row of data then Add subsequent rows. If the numberOfRowsInSection is set to 0, the title for the 3rd section comes close to the title for the 2nd section and it looks ugly. The best that I could come with, and I don't know to do it, is to have a fake graphic placeholder on the striped background (between the 2nd and third titles) that looks like a single row in the 2nd section, put "Enter Data Here..." text in the graphic, and then the first row of actual data entered and all subsequent rows will cover it up. Can anyone tell me how to do this or offer a better suggestion. Thanks.

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• Web.Routing for the site root or homepage

  - by Aquinas

  I am doing some work with Web.Routing, using it to have friendly urls and nice Rest like interfaces to a site that is essentially rendered by a single IHttpHandler. There are no webforms, the handler generates all the html/json and writes it as part of process request. This works well for things like /Sites/Accounting for example, but I can't get it to work for the site root, i.e. '/'. I have tried registering a route with an empty string, with 'default.aspx' (which is the empty aspx file I keep in my root folder to play nice with cassini and iis). I set RouteExistingFiles to false explicitly, but whatever I do when hitting the root url it still opens default.axpx, which has no code it inherits from, and contains a simple h1 tag to show that I've hit it. I don't want to change the default file to redirect to a desired route, I just want the equivalent of a 'default' route that is applied when no other routes are found, similar to MVC. For reference, the previous version of the site didn't use Web.Routing, but had a handler referenced in the web.config that was perfectly capable of intercepting requests for the root or default.aspx. Specs: ASP.NET 3.5sp1, C#, no webforms, MVC or openrasta. Plain old IHttpHandlers.

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• Simple Select Statement on MySQL Database Hanging

  - by AlishahNovin

  I have a very simple sql select statement on a very large table, that is non-normalized. (Not my design at all, I'm just trying to optimize while simultaneously trying to convince the owners of a redesign) Basically, the statement is like this: SELECT FirstName, LastName, FullName, State FROM Activity Where (FirstName=@name OR LastName=@name OR FullName=@name) AND State=@state; Now, FirstName, LastName, FullName and State are all indexed as BTrees, but without prefix - the whole column is indexed. State column is a 2 letter state code. What I'm finding is this: When @name = 'John Smith', and @state = '%' the search is really fast and yields results immediately. When @name = 'John Smith', and @state = 'FL' the search takes 5 minutes (and usually this means the web service times out...) When I remove the FirstName and LastName comparisons, and only use the FullName and State, both cases above work very quickly. When I replace FirstName, LastName, FullName, and State searches, but use LIKE for each search, it works fast for @name='John Smith%' and @state='%', but slow for @name='John Smith%' and @state='FL' When I search against 'John Sm%' and @state='FL' the search finds results immediately When I search against 'John Smi%' and @state='FL' the search takes 5 minutes. Now, just to reiterate - the table is not normalized. The John Smith appears many many times, as do many other users, because there is no reference to some form of users/people table. I'm not sure how many times a single user may appear, but the table itself has 90 Million records. Again, not my design... What I'm wondering is - though there are many many problems with this design, what is causing this specific problem. My guess is that the index trees are just too large that it just takes a very long time traversing the them. (FirstName, LastName, FullName) Anyway, I appreciate anyone's help with this. Like I said, I'm working on convincing them of a redesign, but in the meantime, if I someone could help me figure out what the exact problem is, that'd be fantastic.

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• The cost of passing by shared_ptr

  - by Artem

  I use std::tr1::shared_ptr extensively throughout my application. This includes passing objects in as function arguments. Consider the following: class Dataset {...} void f( shared_ptr< Dataset const > pds ) {...} void g( shared_ptr< Dataset const > pds ) {...} ... While passing a dataset object around via shared_ptr guarantees its existence inside f and g, the functions may be called millions of times, which causes a lot of shared_ptr objects being created and destroyed. Here's a snippet of the flat gprof profile from a recent run: Each sample counts as 0.01 seconds. % cumulative self self total time seconds seconds calls s/call s/call name 9.74 295.39 35.12 2451177304 0.00 0.00 std::tr1::__shared_count::__shared_count(std::tr1::__shared_count const&) 8.03 324.34 28.95 2451252116 0.00 0.00 std::tr1::__shared_count::~__shared_count() So, ~17% of the runtime was spent on reference counting with shared_ptr objects. Is this normal? A large portion of my application is single-threaded and I was thinking about re-writing some of the functions as void f( const Dataset& ds ) {...} and replacing the calls shared_ptr< Dataset > pds( new Dataset(...) ); f( pds ); with f( *pds ); in places where I know for sure the object will not get destroyed while the flow of the program is inside f(). But before I run off to change a bunch of function signatures / calls, I wanted to know what the typical performance hit of passing by shared_ptr was. Seems like shared_ptr should not be used for functions that get called very often. Any input would be appreciated. Thanks for reading. -Artem

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• xsd.exe - schema to class - for use with WCF

  - by NealWalters

  I have created a schema as an agreed upon interface between our company and an external company. I am now creating a WCF C# web service to handle the interface. I ran the XSD utility and it created a C# class. The schema was built in BizTalk, and references other schemas, so all-in-all there are over 15 classes being generated. I put [DataContract} attribute in front of each of the classes. Do I have to put the [DataMember] attribute on every single property? When I generate a test client program, the proxy does not have any code for any of these 15 classes. We used to use this technique when using .asmx services, but not sure if it will work the same with WCF. If we change the schema, we would want to regenerate the WCF class, and then we would haev to each time redecorate it with all the [DataMember] attributes? Is there an newer tool similar to XSD.exe that will work better with WCF? Thanks, Neal Walters SOLUTION (buried in one of Saunders answer/comments): Add the XmlSerializerFormat to the Interface definition: [OperationContract] [XmlSerializerFormat] // ADD THIS LINE Transaction SubmitTransaction(Transaction transactionIn); Two notes: 1) After I did this, I saw a lot more .xsds in the my proxy (Service Reference) test client program, but I didn't see the new classes in my intellisense. 2) For some reason, until I did a build on the project, I didn't get all the classes in the intellisense (not sure why).

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• DB2Command ExecuteNonQuery Insert multiple rows problem

  - by DB2 Nubie

  I'm attempting to insert multiple rows into a DB2 database using C# code like this: string query = "INSERT INTO TESTDB2.RG_Table (V,E,L,N,Q,B,S,P) values" + "('lkjlkj', 'iouoiu', '2009-03-27 12:01:19', 'nnne', 'sdfdf', NULL, NULL, NULL)," + "('lkjlk2', 'iuoiu2', '2009-03-27 12:01:19', 'nnne2', 'sddf2', NULL, NULL, NULL)"; DB2Command cmd = new DB2Command(query, this.transactionConnection, this.transaction); cmd.ExecuteNonQuery(); If I stop building the query string after the first set of values is included it executes without an error. Attempting to load multiple values using this method results in the following error: Upload error : ERROR [42601] [IBM][DB2] SQL0104N An unexpected token "," was found following "". Expected tokens may include: "". SQLSTATE =42601 The SQL syntax matches that which I have read elsewhere, such as http://stackoverflow.com/questions/452859/inserting-multiple-rows-in-a-single-sql-query and IBM's documentation gives this example: cmd = conn.CreateCommand(); cmd.Transaction = trans; cmd.CommandText = "INSERT INTO company_a VALUES(5275, 'Sanders', 20, 'Mgr', 15, 18357.50), " + "(5265, 'Pernal', 20, 'Sales', NULL, 18171.25), " + "(5791, 'O''Brien', 38, 'Sales', 9, 18006.00)"; cmd.ExecuteNonQuery(); Can anyone explain what could account for this?

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• Boost Mersenne Twister: how to seed with more than one value?

  - by Eamon Nerbonne

  I'm using the boost mt19937 implementation for a simulation. The simulation needs to be reproducible, and that means storing and potentially reusing the RNG seeds later. I'm using the windows crypto api to generate the seed values because I need an external source for the seeds and not because of any particular guarantees of randomness. The output of any simulation run will have a note including the RNG seed - so the seed needs to be reasonably short. On the other hand, as part of the analysis of the simulation, I'll be comparing several runs - but to be sure that these runs are actually different, I'll need to use different seeds - so the seed needs to be long enough to avoid accidental collisions. I've determined that 64-bits of seeding should suffice; the chance of a collision will reach 50% after about 2^32 runs - that probability is low enough that the average error caused by it is negligible to me. Using just 32-bits of seed is tricky; the chance of a collision reaches 50% already after 2^16 runs; and that's a little too likely for my tastes. Unfortunately, the boost implementation either seeds with a full state vector - which is far, far too long - or a single 32-bit unsigned long - which isn't ideal. How can I seed the generator with more than 32-bits but less than a full state vector? I tried just padding the vector or repeating the seeds to fill the state vector, but even a cursory glance at the results shows that that generates poor results.

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• C# Windows Service

  - by Goober

  Scenario I've created a windows service, but whenever I start it, it stops immediately. The service was concieved from a console application that used to subscribe to an event and watch processes on a server. If anything happened to process (i.e. It was killed), then the event would trigger the process to be restarted. The reason I'm telling you this is because the original code used to look like this: Original Console App Code: static void Main(string[] args) { StartProcess sp = new StartProcess(); //Note the readline that means the application sits here waiting for an event! Console.ReadLine(); } Now that this code has been turned into a Windows Service, it is essentially EXACTLY THE SAME. However, the service does not sit there waiting, even with the readline, it just ends..... New Windows Service Code: protected override void OnStart(string[] args) { ProcessMonitor pm = new ProcessMonitor(); Console.ReadLine(); } Thoughts Since the functionality is entirely encapsulated within this single class (It quite literally starts, sets up some events and waits) - How can I get the service to actually sit there and just wait? It seems to be ignoring the readline. However this works perfectly as a console application, it is just far more convenient to have it as a service.

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• Lucene complex structure search

  - by archer

  Basically I do have pretty simple database that I'd like to index with Lucene. Domains are: // Person domain class Person { Set<Pair> keys; } // Pair domain class Pair { KeyItem keyItem; String value; } // KeyItem domain, name is unique field within the DB (!!) class KeyItem{ String name; } I've tens of millions of profiles and hundreds of millions of Pairs, however, since most of KeyItem's "name" fields duplicates, there are only few dozens KeyItem instances. Came up to that structure to save on KeyItem instances. Basically any Profile with any fields could be saved into that structure. Lets say we've profile with properties - name: Andrew Morton - eduction: University of New South Wales, - country: Australia, - occupation: Linux programmer. To store it, we'll have single Profile instance, 4 KeyItem instances: name, education,country and occupation, and 4 Pair instances with values: "Andrew Morton", "University of New South Wales", "Australia" and "Linux Programmer". All other profile will reference (all or some) same instances of KeyItem: name, education, country and occupation. My question is, how to index all of that so I can search for Profile for some particular values of KeyItem::name and Pair::value. Ideally I'd like that kind of query to work: name:Andrew* AND occupation:Linux* Should I create custom Indexer and Searcher? Or I could use standard ones and just map KeyItem and Pair as Lucene components somehow?

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• Has anyone used Rational Team Concert (RTC)?

  - by FryGuy

  The company I work for is currently evaluating replacements for SourceSafe, and for various reasons, I think RTC will be chosen. I'm a little scared that we're going to end up with a solution that isn't the best for us in our situation. I've tried researching a little bit about what it is, but all I have been able to find are marketing things, but nothing about how it actually works (any of the paradigms it uses, etc). Our team is around 8 developers and 2 QA people on a single project (and 4-5 more people that would be using it for their independent project). It seems like RTC is targetted for larger teams, but our team is relatively small. Does anyone has experience using RTC in a smaller team? The project that would be using it is a .NET/WPF application, so we would be using primarily Visual Studio. Is the Visual Studio integration any good, or are we stuck having to have Eclipse open on top of Visual Studio? Personally, I have been using Bazaar as my personal source control (and checking out/into sourcesafe from a branch), as well as on personal projects. Does RTC incorporate features of "third generation" version control systems, such as first class branching/merging and changesets rather than file changes, and good visualization of where changes come from? Also, what are the general pros and cons for it?

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• Using R in Processing through rJava/JRI?

  - by tommy-o-dell

  Hi guys, Is it possible to run R in Processing through rJava/JRI? If I deployed a Processing app on the web, would the client need R on their system? I'm looking to create an interactive information dashboard that I can deploy on the web. It seems that Processing is probably my best bet for the interactive/web part of things. Unfortunately, it doesn't look like there are many math/stats functions built-in. And there aren't any libraries for plotting data either. I've been using R and gpplot2 for a few months and am thrilled (amazed) at how easily it manipulates and plots data. So I'm wondering now if can get the best of both worlds and run R through a Processing applet. From the JRI website: JRI is a Java/R Interface, which allows to run R inside Java applications as a single thread. Basically it loads R dynamic library into Java and provides a Java API to R functionality. It supports both simple calls to R functions and a full running REPL. In a sense JRI is the inverse of rJava and both can be combined (i.e. you can run R code inside JRI that calls back to the JVM via rJava). The JGR project makes the full use of both JRI and rJava to provide a full Java GUI for R. JRI uses native code, but it supports all platforms where Sun's Java (or compatible) is available, including Windows, Mac OS X, Sun and Linux (both 32-bit and 64-bit). Thanks for the advice :)

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