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  • Extracting noun+noun or (adj|noun)+noun from Text

    - by ssuhan
    I would like to query if it is possible to extract noun+noun or (adj|noun)+noun in R package openNLP?That is, I would like to use linguistic filtering to extract candidate noun phrases. Could you direct me how to do? Many thanks. Thanks for the responses. here is the code: library("openNLP") acq <- "Gulf Applied Technologies Inc said it sold its subsidiaries engaged in pipeline and terminal operations for 12.2 mln dlrs. The company said the sale is subject to certain post closing adjustments, which it did not explain. Reuter." acqTag <- tagPOS(acq) acqTagSplit = strsplit(acqTag," ") acqTagSplit qq = 0 tag = 0 for (i in 1:length(acqTagSplit[[1]])){ qq[i] <-strsplit(acqTagSplit[[1]][i],'/') tag[i] = qq[i][[1]][2] } index = 0 k = 0 for (i in 1:(length(acqTagSplit[[1]])-1)) { if ((tag[i] == "NN" && tag[i+1] == "NN") | (tag[i] == "NNS" && tag[i+1] == "NNS") | (tag[i] == "NNS" && tag[i+1] == "NN") | (tag[i] == "NN" && tag[i+1] == "NNS") | (tag[i] == "JJ" && tag[i+1] == "NN") | (tag[i] == "JJ" && tag[i+1] == "NNS")){ k = k +1 index[k] = i } } index Reader can refer index on acqTagSplit to do noun+noun or (adj|noun)+noun extractation. (The code is not optimum but work. If you have any idea, please let me know.) Furthermore, I still have a problem. Justeson and Katz (1995) proposed another linguistic filtering to extract candidate noun phrases: ((Adj|Noun)+|((Adj|Noun)(Noun-Prep)?)(Adj|Noun))Noun I cannot well understand its meaning, could someone do me a favor to explain it or transform such representation into R language

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  • What are the lengths/limits C preprocessor as a language creation tool? Where can I learn more about

    - by Weston C
    In his FAQ @ http://www2.research.att.com/~bs/bs_faq.html#bootstrapping, Bjarne Stroustrup says: To build [Cfront, the first C++ compiler], I first used C to write a "C with Classes"-to-C preprocessor. "C with Classes" was a C dialect that became the immediate ancestor to C++... I then wrote the first version of Cfront in "C with Classes". When I read this, it piqued my interest in the C preprocessor. I'd seen its macro capabilities as suitable for simplifying common expressions but hadn't thought about its ability to significantly add to syntax and semantics on the level that I imagine bringing classes to C took. So now I have a couple of questions on my mind: 1) Are there other examples of this approach to bootstrapping a language off of C? 2) Is the source to Stroustrup's original work available anywhere? 3) Where could I learn more about the specifics of utilizing this technique? 4) What are the lengths/limits of that approach? Could one, say, create a set of preprocessor macros that let someone write in something significantly Lisp/Scheme like?

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  • How do I find all paths through a set of given nodes in a DAG?

    - by Hanno Fietz
    I have a list of items (blue nodes below) which are categorized by the users of my application. The categories themselves can be grouped and categorized themselves. The resulting structure can be represented as a Directed Acyclic Graph (DAG) where the items are sinks at the bottom of the graph's topology and the top categories are sources. Note that while some of the categories might be well defined, a lot is going to be user defined and might be very messy. Example: On that structure, I want to perform the following operations: find all items (sinks) below a particular node (all items in Europe) find all paths (if any) that pass through all of a set of n nodes (all items sent via SMTP from example.com) find all nodes that lie below all of a set of nodes (intersection: goyish brown foods) The first seems quite straightforward: start at the node, follow all possible paths to the bottom and collect the items there. However, is there a faster approach? Remembering the nodes I already passed through probably helps avoiding unnecessary repetition, but are there more optimizations? How do I go about the second one? It seems that the first step would be to determine the height of each node in the set, as to determine at which one(s) to start and then find all paths below that which include the rest of the set. But is this the best (or even a good) approach? The graph traversal algorithms listed at Wikipedia all seem to be concerned with either finding a particular node or the shortest or otherwise most effective route between two nodes. I think both is not what I want, or did I just fail to see how this applies to my problem? Where else should I read?

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  • ReaderWriterLockSlim and Pulse/Wait

    - by Jono
    Is there an equivalent of Monitor.Pulse and Monitor.Wait that I can use in conjunction with a ReaderWriterLockSlim? I have a class where I've encapsulated multi-threaded access to an underlying queue. To enqueue something, I acquire a lock that protects the underlying queue (and a couple of other objects) then add the item and Monitor.Pulse the locked object to signal that something was added to the queue. public void Enqueue(ITask task) { lock (mutex) { underlying.Enqueue(task); Monitor.Pulse(mutex); } } On the other end of the queue, I have a single background thread that continuously processes messages as they arrive on the queue. It uses Monitor.Wait when there are no items in the queue, to avoid unnecessary polling. (I consider this to be good design, but any flames (within reason) are welcome if they help me learn otherwise.) private void DequeueForProcessing(object state) { while (true) { ITask task; lock (mutex) { while (underlying.Count == 0) { Monitor.Wait(mutex); } task = underlying.Dequeue(); } Process(task); } } As more operations are added to this class (requiring read-only access to the lock protected underlying), someone suggested using ReaderWriterLockSlim. I've never used the class before, and assuming it can offer some performance benefit, I'm not against it, but only if I can keep the Pulse/Wait design.

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  • Seam @Factory in abstract base class?

    - by Shadowman
    I've got a series of web actions I'm implementing in Seam to perform create, read, update, etc. operations. For my read/update/delete actions, I'd like to have individual action classes that all extend an abstract base class. I'd like to put the @Factory method in the abstract base class to retrieve the item that is to be acted upon. For example, I have this as the base class: public abstract class BaseAction { @In(required=false)@Out(required=false) private MyItem item=null; public MyItem getItem(){...} public void setItem(...){...} @Factory("item") public void initItem(){...} } My subclasses would extend BaseAction, so that I don't have to repeat the logic to load the item that is to be viewed, deleted, updated, etc. However, when I start my application, Seam throws errors saying I have declared multiple @Factory's for the same object. Is there any way around this? Is there any way to provide the @Factory in the base class without encoutnering these errors?

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  • How can I improve the performance of LinqToSql queries that use EntitySet properties?

    - by DanM
    I'm using LinqToSql to query a small, simple SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of what makes LinqToSql so appealing. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance besides resorting to doing all the joins manually? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view. Update Here are the table definitions for the example I used in my question: create table Order ( Id int identity(1, 1) primary key, ProductName ntext null ) create table Customer ( Id int identity(1, 1) primary key, OrderId int null references Order (Id) )

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  • Improving I/O performance in C++ programs[external merge sort]

    - by Ajay
    I am currently working on a project involving external merge-sort using replacement-selection and k-way merge. I have implemented the project in C++[runs on linux]. Its very simple and right now deals with only fixed sized records. For reading & writing I use (i/o)fstream classes. After executing the program for few iterations, I noticed that I/O read blocks for requests of size more than 4K(typical block size). Infact giving buffer sizes greater than 4K causes performance to decrease. The output operations does not seem to need buffering, linux seemed to take care of buffering output. So I issue a write(record) instead of maintaining special buffer of writes and then flushing them out at once using write(records[]). But the performance of the application does not seem to be great. How could I improve the performance? Should I maintain special I/O threads to take care of reading blocks or are there existing C++ classes providing this abstraction already?(Something like BufferedInputStream in java)

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  • Is it possible to send OSC commands to an iPad via the Camera Connection Kit?

    - by HELVETICADE
    I'm building a small controller device that I'd like to partner with a computer. I've settled on using OSC out from my custom built hardware and am pretty satisfied with what I can get from WOscLib. Two goals I'd like to achieve are portability and a very nice ratio between battery:computing power, and this has lured me towards using iPhoneOS to accomplish my goals. I think the iPad would suit my needs perfectly, except that using wifi to broadcast OSC out from my device requires that device to be connected to a third device with a wifi chip, and this would destroy the goal of portability, whilst also introducing potential latency and stability headaches. My question is pretty simple: Can I push OSC commands FROM my controller TO an iPad via USB and the Camera Connection Kit? If I could accomplish this, the two major goals of my project would be fulfilled very nicely. This seems like it should be a simple little question, but researching this obsessively over the past few weeks has left me more almost more uncertain than if I had done no research at all. I'd really like some more confidence before I go down this route, and it seems like it should be possible. Any insight would be very, very appreciated.

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  • What are the skills a Drupal Developer needs?

    - by hfidgen
    I'm trying to write out a list of key Drupal competencies, mainly so I can confirm what I know, don't know and don't know I don't know. (Thanks D. Rumsfeld for that quote!) I think some of these are really broad, for instance there's quite a difference between making a functional theme and creating a theme with good SEO, load times and so on, but I'm hoping you could assume that a half decent web developer would look after that anyway. Just interested to see what people here feel is also important. Able to install Drupal on a server (pretty obvious). Able to research and install modules to meet project requirements Able to configure all the basic modules and core settings to get a site running Able to create a custom Theme from scratch which validates with good HTML/CSS and also pays attention to usability and accessibility. (Whilst still looking kick-ass). Able to use Hooks in the theme template.php to alter forms, page layout and other core functionality Can make forms from scratch using the API - with validation and posting back to the DB/email Can use Views to create blocks or pages, use php snippets as arguments, etc. Can create custom modules from scratch utilising core hooks and other hooks.

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  • iPhone: Does it ever make sense for an object to retain its delegate?

    - by randombits
    According to the rules of memory management in a non garbage collected world, one is not supposed to retain a the calling object in a delegate. Scenario goes like this: I have a class that inherits from UITableViewController and contains a search bar. I run expensive search operations in a secondary thread. This is all done with an NSOperationQueue and subclasses NSOperation instances. I pass the controller as a delegate that adheres to a callback protocol into the NSOperation. There are edge cases when the application crashes because once an item is selected from the UITableViewController, I dismiss it and thus its retain count goes to 0 and dealloc gets invoked on it. The delegate didn't get to send its message in time as the results are being passed at about the same time the dealloc happens. Should I design this differently? Should I call retain on my controller from the delegate to ensure it exists until the NSOperation itself is dealloc'd? Will this cause a memory leak? Right now if I put a retain on the controller, the crashes goes away. I don't want to leak memory though and need to understand if there are cases where retaining the delegate makes sense. Just to recap. UITableViewController creates an NSOperationQueue and NSOperation that gets embedded into the queue. The UITableViewController passes itself as a delegate to NSOperation. NSOperation calls a method on UITableViewController when it's ready. If I retain the UITableViewController, I guarantee it's there, but I'm not sure if I'm leaking memory. If I only use an assign property, edge cases occur where the UITableViewController gets dealloc'd and objc_msgSend() gets called on an object that doesn't exist in memory and a crash is imminent.

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  • Mysql Performance Question - Essentially about normalizing efficiency

    - by freqmode
    Hi there. Just a quick question about database performance. I'll outline my site purpose below as background. I'm creating a dictionary site that saves the words users define to a database. What I'm wondering is whether or not to create a words table for each user or to keep one massive words table. This site will be used for entire schools so the single words table would be massive! The database structure is as follows: A user table with: User_ID PRIMARY KEY Username First Last Password Email Country Research Standings SendInfo Donated JoinedOn LastLogin Logins Correct Attempts Admin Active And one word table with: User_ID PRIMARY KEY Word Vocab Spell Defined DefinedAttempted Spelled SpelledAttempted Sentenced SentencedAttempted So what I'm asking is , performance-wise, should I create a new table for each user when they join the site - each user could have hundreds or thousands of words over time? Or is it better to have one massive table with thousands and thousands of records and filter by User_ID. I don't think I'll perform many table joins. My gut feeling is to create a new table for each user, but I thought I'd ask for expert advice! Thanks in advance.

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  • Are there any libraries for parsing "number expressions" like 1,2-9,33- in Java

    - by mihi
    Hi, I don't think it is hard, just tedious to write: Some small free (as in beer) library where I can put in a String like 1,2-9,33- and it can tell me whether a given number matches that expression. Just like most programs have in their print range dialogs. Special functions for matching odd or even numbers only, or matching every number that is 2 mod 5 (or something like that) would be nice, but not needed. The only operation I have to perform on this list is whether the range contains a given (nonnegative) integer value; more operations like max/min value (if they exist) or an iterator would be nice, of course. What would be needed that it does not occupy lots of RAM if anyone enters 1-10000000 but the only number I will ever query is 12345 :-) (To implement it, I would parse a list into several (min/max/value/mod) pairs, like 1,10,0,1 for 1-10 or 11,33,1,2 for 1-33odd, or 12,62,2,10 for 12-62/10 (i. e. 12, 22, 32, ..., 62) and then check each number for all the intervals. Open intervals by using Integer.MaxValue etc. If there are no libs, any ideas to do it better/more efficient?)

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  • Export GridView to Excel (not working)

    - by Chiramisu
    I've spent the last two days trying to get some bloody data to export to Excel. After much research I determined that the best and most common way is using HttpResponse headers as shown in my code below. After stepping through countless times in debug mode, I have confirmed that the data is in fact there and both filtered and sorted the way I want it. However, it does not download as an Excel file, or do anything at all for that matter. I suspect this may have something to do with my UpdatePanel or perhaps the ImageButton not posting back properly, but I'm not sure. What am I doing wrong? Please help me to debug this issue. I will be eternally grateful. Thank you. :) Markup <asp:UpdatePanel ID="statusUpdatePanel" runat="server" UpdateMode="Conditional"> <Triggers> <asp:AsyncPostBackTrigger ControlID="btnExportXLS" EventName="Click" /> </Triggers> <ContentTemplate> <asp:GridView ID="GridView1" runat="server" AllowPaging="True" PageSize="10" AllowSorting="True" DataSourceID="GridView1SDS" DataKeyNames="ID"> </asp:GridView> <span><asp:ImageButton ID="btnExportXLS" runat="server" /></span> </ContentTemplate> </asp:UpdatePanel> Codebehind Protected Sub ExportToExcel() Handles btnExportXLS.Click Dim dt As New DataTable() Dim da As New SqlDataAdapter(SelectCommand, ConnectionString) da.Fill(dt) Dim gv As New GridView() gv.DataSource = dt gv.DataBind() Dim frm As HtmlForm = New HtmlForm() frm.Controls.Add(gv) Dim sw As New IO.StringWriter() Dim hw As New System.Web.UI.HtmlTextWriter(sw) Response.ContentType = "application/vnd.ms-excel" Response.AddHeader("content-disposition", "attachment;filename=Report.xls") Response.Charset = String.Empty gv.RenderControl(hw) Response.Write(sw.ToString()) Response.End() End Sub

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  • Plist data OK in iPhone simulator but disappears after installation onto device

    - by user183804
    I am testing an application on a first-generation iPod running OS 3.1.3 with a tableview populated from a plist. The application works well on the simulator. Initially after installation onto the iPod for testing, the tableview was blank (scrollable lines present, but empty rows). After searching this site, I found one issue to be a case-sensitive problem in the name of the plist file ("Data.plist in resources; "data.plist" in code). When the problem persisted, I again found on this site the advice to "Clean all Targets" prior to installation. I now have found that after performing a "Clean all Targets" operation twice, quitting XCode in between operations, the problem resolves, and the tableview appears properly populated after installation. I am wondering whether this issue signifies a corrupted plist file, prior to making the application available on the App store. Re-creating the plist file from scratch and then testing it likely would take several hours of work, so I do not want to do so unless absolutely necessary. Thanks in advance for any help.

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  • Detaching all entities of T to get fresh data

    - by Goran
    Lets take an example where there are two type of entites loaded: Product and Category, Product.CategoryId - Category.Id. We have available CRUD operations on products (not Categories). If on another screen Categories are updated (or from another user in the network), we would like to be able to reload the Categories, while preserving the context we currently use, since we could be in the middle of editing data, and we do not want changes to be lost (and we cannot depend on saving, since we have incomplete data). Since there is no easy way to tell EF to get fresh data (added, removed and modified), we thought of twp possible ways: 1) Getting products attached to context, and categories detached from context. This would mean that we loose the ability to access Product.Category.Name, which we do sometimes require, so we would need to manually resolve it (example when printing data). 2) detaching / attaching all Categories from current context. Context.ChangeTracker.Entries().Where(x => x.Entity.GetType() == typeof(T)).ForEach(x => x.State = EntityState.Detached); And then reload the categories, which will get fresh data. Do you find any problem with this second approach? We understand that this will require all constraints to be put on foreign keys, and not navigation properties, since when detaching all Categories, Product.Category navigation properties would be reset to null also. Also, there could be a potential performance problem, which we did not test, since there could be couple of thousand products loaded, and all would need to resolve navigation property when reloading. Which of the two do you prefer, and is there a better way (EF6 + .NET 4.0)?

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  • Extracting function declarations from a PHP file

    - by byronh
    I'm looking to create an on-site API reference for my framework and application. Basically, say I have a class file model.class.php: class Model extends Object { ... code here ... // Separates results into pages. // Returns Paginator object. final public function paginate($perpage = 10) { ... more code here ... } } and I want to be able to generate a reference that my developers can refer to quickly in order to know which functions are available to be called. They only need to see the comments directly above each function and the declaration line. Something like this (similar to a C++ header file): // Separates results into pages. // Returns Paginator object. final public function paginate($perpage = 10); I've done some research and this answer looked pretty good (using Reflection classes), however, I'm not sure how I can keep the comments in. Any ideas? EDIT: Sorry, but I want to keep the current comment formatting. Myself and the people who are working on the code hate the verbosity associated with PHPDocumentor. Not to mention a comment-rewrite of the entire project would take years, so I want to preserve just the // comments in plaintext.

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  • Doing a POST to a Service Operation in ADO.NET data services

    - by DataServices123
    Is it possible to POST to a service operation defined in an ADO.NET data service (it is decorated with WebInvoke)? I had no problem calling the service operation as an HTTP GET. However, when I switched to doing a POST, the stack trace consistently comes back with "Parameter cannot be NULL". I am using the jQuery syntax below, and sending the POST as JSON (though I'm not including the $.ajax call, the parameter names line up exactly). It would be possible to try this with WCF, as opposed to ADO.NET data services (newly renamed as WCF data services). However, my preference would be to use this approach first. I have tried this with and without the stringify method. Most examples online only show how to use a POST to entities (i.e. for handling CRUD operations). However, in this case we are POSTing to a Service Operation. function PostToDataService() { varType = "POST"; varUrl = "http://dev-server/MyServices/MyService.svc/SampleSO"; varData = { CustomMessage: $("#TextBox1").val() }; varData = JSON.stringify(varData); varContentType = "application/json; charset=utf-8"; varDataType = "json"; varProcessData = true; CallService(); }

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  • Word forms with too many ActiveX checkboxes load slowly.

    - by Luke
    Hi there, my company's software product has a feature that allows users to generate forms from Word templates. The program auto fills some fields from the SQL database and the user can fill in other data that they desire. So we have a .dotx template that holds the design of the form, and then the user gets the .docx file to fill out when they call it from our program. The problem we're having is that some of our users have been finding that the forms take an exceptionally long time to open up and then, once open, are so slow to respond (scroll around, etc) that they're unusable. So in my investigations so far, I've found out that the problem systems are one with lower powered CPUs (unfortunately it happens for systems above our system requirements) and the Word forms that cause the problems are ones with large amount of ActiveX style checkboxes on them. I verified that reducing the ActiveX checkboxes fixes the form loading problems. So I have the following questions about solutions (we're using Word 2007): 1) Is there any way to configure Word, or some other settings, so that there won't be such a strain opening a Word form with lots of ActiveX checkboxes? Any way of speeding up Word's opening? 2) Using Legacy style checkboxes instead of the ActiveX ones makes the forms load fine, but it looks like the user has to double-click the checkbox and change Default Value-Checked. Is there a way to configure it so that they can simply click on the checkbox to tick it? "Legacy Forms" checkbox as a name kind of worries me (Legacy…), does that mean a future version of word at some point wouldn't load the checkboxes because they're "legacy"? 3) Yes, it became clear to me after a little bit of research into solutions that Word is not the tool for the job for forms like I'm describing. InfoPath seems to be exactly what we should have been using all along but unfortunately I wasn't involved in the decision making or development of these forms, just tasked with coming up with a solution. I'd appreciate answers to any of these, or if anyone has any other ideas for solutions to this problem. Thanks

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  • C++ Declarative Parsing Serialization

    - by Martin York
    Looking at Java and C# they manage to do some wicked processing based on special languaged based anotation (forgive me if that is the incorrect name). In C++ we have two problems with this: 1) There is no way to annotate a class with type information that is accessable at runtime. 2) Parsing the source to generate stuff is way to complex. But I was thinking that this could be done with some template meta-programming to achieve the same basic affect as anotations (still just thinking about it). Like char_traits that are specialised for the different types an xml_traits template could be used in a declaritive way. This traits class could be used to define how a class is serialised/deserialized by specializing the traits for the class you are trying to serialize. Example Thoughs: template<typename T> struct XML_traits { typedef XML_Empty Children; }; template<> struct XML_traits<Car> { typedef boost::mpl::vector<Body,Wheels,Engine> Children; }; template<typename T> std::ostream& Serialize(T const&) { // my template foo is not that strong. // but somthing like this. boost::mpl::for_each<typename XML_Traits<T>::Children,Serialize>(data); } template<> std::ostream& Serialize<XML_Empty>(T const&) { /* Do Nothing */ } My question is: Has anybody seen any projects/decumentation (not just XML) out there that uses techniques like this (template meta-programming) to emulate the concept of annotation used in languges like Java and C# that can then be used in code generation (to effectively automate the task by using a declaritive style). At this point in my research I am looking for more reading material and examples.

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  • How do I add code automatically to a derived function in C++

    - by Ian
    I have code that's meant to manage operations on both a networked client and a server, since there is significant overlap between the two. However, there are a few functions here and there that are meant to be exclusively called by the client or server, and accidentally calling a client function on the server (or vice versa) is a significant source of bugs. To reduce these sorts of programming errors, I'm trying to tag functions so that they'll raise a ruckus if they're misused. My current solution is a simple macro at the start of each function that calls an assert if the client or server accesses members they shouldn't. However, this runs into problems when there are multiple derived instances of classes, in that I have to tag the implementation as client or server side in EVERY child class. What I'd like to be able to do is put a tag in the virtual member's signature in the base class, so that I only have to tag it once and not run into errors by forgetting to do it repeatedly. I've considered putting a check in a base class implementation and then referring to it with something like base::functionName, but that runs into the same issue as far as needing to manually add the function call to every implementation. Ideally, I'd be able to have parent versions of the function called automatically like default constructors do. Does anybody know how to achieve something like this in C++? Is there an alternate approach I should be considering? Thanks!

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  • What should i do for accomodating large scale data storage and retrieval?

    - by kailashbuki
    There's two columns in the table inside mysql database. First column contains the fingerprint while the second one contains the list of documents which have that fingerprint. It's much like an inverted index built by search engines. An instance of a record inside the table is shown below; 34 "doc1, doc2, doc45" The number of fingerprints is very large(can range up to trillions). There are basically following operations in the database: inserting/updating the record & retrieving the record accoring to the match in fingerprint. The table definition python snippet is: self.cursor.execute("CREATE TABLE IF NOT EXISTS `fingerprint` (fp BIGINT, documents TEXT)") And the snippet for insert/update operation is: if self.cursor.execute("UPDATE `fingerprint` SET documents=CONCAT(documents,%s) WHERE fp=%s",(","+newDocId, thisFP))== 0L: self.cursor.execute("INSERT INTO `fingerprint` VALUES (%s, %s)", (thisFP,newDocId)) The only bottleneck i have observed so far is the query time in mysql. My whole application is web based. So time is a critical factor. I have also thought of using cassandra but have less knowledge of it. Please suggest me a better way to tackle this problem.

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  • Java-Eclipse-Spring 3.1 - the fastest way to get familiar with this set

    - by Leron
    I, know almost all of you at some point of your life as a programmer get to the point where you know (more or less) different technologies/languages/IDEs and a times come when you want to get things together and start using them once - more efficient and second - more closely to the real life situation where in fact just knowing Java, or some experience with Eclipse doesn't mean nothing, and what makes you a programmer worth something is the ability to work with the combination of 2 or more combinations. Having this in mind here is my question - what do you think is the optimal way of getting into Java+Eclipse+Spring3.1 world. I've read, and I've read a lot. I started writing real code but almost every step is discovering the wheel again and again, wondering how to do thing you know are some what trivial, but you've missed that one article where this topic was discussed and so on. I don't mind for paying for a good tutorial like for example, after a bit of research I decided that instead of losing a lot of time getting the different parts together I'd rather pay for the videos in http://knpuniversity.com/screencast/starting-in-symfony2-tutorial and save myself a lot of time (I hope) and get as fast as possible to writing a real code instead of wondering what do what and so on. But I find it much more difficult to find such sources of info especially when you want something more specific as me and that's the reason to ask this question. I know a lot of you go through the hard way, and I won't give up if I have to do the same, but to be honest I really hope to get post with good tutorials on the subject (paid or not) because in my situation time is literally money. Thanks Leron

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  • How to efficiently store and update binary data in Mongodb?

    - by Rocketman
    I am storing a large binary array within a document. I wish to continually add bytes to this array and sometimes change the value of existing bytes. I was looking for some $append_bytes and $replace_bytes type of modifiers but it appears that the best I can do is $push for arrays. It seems like this would be doable by performing seek-write type operations if I had access somehow to the underlying bson on disk, but it does not appear to me that there is anyway to do this in mongodb (and probably for good reason). If I were instead to just query this binary array, edit or add to it, and then update the document by rewriting the entire field, how costly will this be? Each binary array will be on the order of 1-2MB, and updates occur once every 5 minutes and across 1000s of documents. Worse, yet there is no easy way to spread these out (in time) and they will usually be happening close to one another on the 5 minute intervals. Does anyone have a good feel for how disastrous this will be? Seems like it would be problematic. An alternative would be to store this binary data as separate files on disk, implement a thread pool to efficiently manipulate the files on disk, and reference the filename from my mongodb document. (I'm using python and pymongo so I was looking at pytables). I'd prefer to avoid this though if possible. Is there any other alternative that I am overlooking here? Thanks in advnace.

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  • Parallel.For Batching

    - by chibacity
    Is there built-in support in the TPL for batching operations? I was recently playing with a routine to carry out character replacement on a character array which required a lookup table i.e. transliteration: for (int i = 0; i < chars.Length; i++) { char replaceChar; if (lookup.TryGetValue(chars[i], out replaceChar)) { chars[i] = replaceChar; } } I could see that this could be trivially parallelized, so jumped in with a first stab which I knew would perform worse as the tasks were too fine-grained: Parallel.For(0, chars.Length, i => { char replaceChar; if (lookup.TryGetValue(chars[i], out replaceChar)) { chars[i] = replaceChar; } }); I then reworked the algorithm to use batching so that the work could be chunked onto different threads in less fine-grained batches. This made use of threads as expected and I got some near linear speed up. I'm sure that there must be built-in support for batching in the TPL. What is the syntax, and how do I use it? const int CharBatch = 100; int charLen = chars.Length; Parallel.For(0, ((charLen / CharBatch) + 1), i => { int batchUpper = ((i + 1) * CharBatch); for (int j = i * CharBatch; j < batchUpper && j < charLen; j++) { char replaceChar; if (lookup.TryGetValue(chars[j], out replaceChar)) { chars[j] = replaceChar; } } });

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  • Using SMO to call Database.ExecuteNonQuery() concurrently?

    - by JimDaniel
    I have been banging my head against the wall trying to figure out how I can run update scripts concurrently against multiple databases in a single SQL Server instance using SMO. Our environments have an ever-increasing number of databases which need updating, and iterating through one at a time is becoming a problem (too slow). From what I understand SMO does not support concurrent operations, and my tests have bore that out. There seems to be shared memory at the Server object level, for things like DataReader context, keeps throwing exceptions such as "reader is already open." I apologize for not having the exact exceptions I am getting. I will try to get them and update this post. I am no expert on SMO and just feeling my way through to be honest. Not really sure I am approaching it the right way, but it's something that has to be done, or our productivity will slow to a crawl. So how would you guys do something like this? Am I using the wrong technology with SMO? All I am wanting to do is execute sql scripts against databases in a single sql server instance in parallel. Thanks for any help you can give, Daniel

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