Search Results

Search found 11226 results on 450 pages for 'reverse thinking'.

Page 384/450 | < Previous Page | 380 381 382 383 384 385 386 387 388 389 390 391  | Next Page >

• The following grammar is LL1, SLR, LR(1), LALR?

  - by Mike

  P - {D ; C} D - d; D| d C - c; C | c a) Is the grammar LL(1)? Explain your answer. b) Is the grammar SLR(1)? Explain your answer. c) Is the grammar LR(1)? Explain your answer. d) Is the grammar LALR? Explain your answer. As for my answers I actually got no for them all... so I'm thinking I did something wrong Here is my explanation. a) It is not LL(1) because it is not left factored. b) It is not SLR, because of the transition diagram item 2 ( which is... ) D- d . ; D D- d . We need to consult the follow set, Follow(D) = ; Therefore this is not SLR c) It is not LR(1) because of... item 1 P- {D.;C} , $ D- .d;D , ; D- .d , ; item 2 D- d.; D , ; D- d. , ; item 3 D- d; . D , ; D- .d;D , ; D- .d , ; Since item 2 goes to item 3 with ;, AND "D- d."'s (in item 2) look ahead token is also ;. this causes a reduce to shift conflict, therefore this grammar is not LR(1) d) This grammar is not LALR because it is not LR(1) Thanks for your help!

  Read the article

• What tasks aren't easy for PHP, ColdFusion and ASP?

  - by boost

  PHP, ColdFusion, and ASP (among many others) are usually sold on their strengths. What are their weaknesses? If one were to develop a niche product to handle the things that these products weren't so good at, what should it focus on? EDIT I'm trying to figure out what things PHP etc are bad at. They're all good at doing the nuts and bolts stuff, if one is looking with a bottom-to-top mindset. I'm thinking a little more globally, more top-to-bottom; what's difficult to achieve in PHP/ASP/CF without thousands of lines of code and twenty minutes of server time? EDIT Suppose company A comes up to you and says, "We want you to do x in PHP." What values of x will cause you to say, "Forget it, buddy, no one in their right mind would use PHP for that"? (swap PHP in the above quote for your favourite tool) EDIT Have we got to the point where everyone's needs can be met with PHP frameworks, Rails and ... er ... Java?

  Read the article

• Best practice for inserting large chunks of HTML into elements with Javscript?

  - by hamstar

  Hey guys. I'm building a web application (using prototype) at the moment that requires the addition of large chunks of HTML into the DOM. Most of these are rows that contain elements with all manner of attributes. Currently I keep a blank row of html in a variable and var blankRow = '<tr><td>' +'<a href="{LINK}" onclick="someFunc(\'{STRING}\');">{WORD}</a>' +'</td></tr>'; function insertRow(o) { newRow = blankRow .sub('{LINK}',o.link) .sub('{STRING}',o.string) .sub('{WORD}',o.word); $('tbodyElem').insert( newRow ); } Now that works all well and dandy, but is it the best practice? I have to update the code in the blankRow when I update code on the page, so the new elements being inserted are the same. It gets sucky when I have like 40 lines of HTML to go in a blankRow and then I have to escape it too. Is there an easier way? I was thinking of urlencoding and then decoding it before insertion but that would still mean a blankRow and lots of escaping. What would be mean would be a eof function a la PHP et al. $blankRow = <<<EOF text text EOF; That would mean no escaping but it would still need a blankRow. What do you do in this situation?

  Read the article

• xcode project-/target-settings-syntax for linker flag force_load on iPhone

  - by Kaiserludi

  Hi all. I am confronted with the double bind, that on the one hand for one of the 3rd party static libraries, my iPhone application uses, the linker flag -all_load has to be set in the application project- or target settings, otherwise the app crashes at runtime not finding some symbols, called internally from the lib, on the other hand for another 3rd party static lib -all_load must not be set on application level, or the app won't build thanks to a "duplicate symbols"-linker error. To solve this issue I now want to use force_load instant of load_all, as it due to documentation it does the same like all_load, but only for the passed path or lib-file, instead of all libs. The problem with force_load is, I do not have a clue, how to pass a path or file as parameter with it, when passing it via xcode project- or target-settings. All syntax-possibilities coming to my mind either lead into xcode thinking its another linker flag instead of a parameter to the previous one, or the linker is throwing syntax related errors or the flag simply does nothing at all in comparison to not being set. I also opened the .pbxproj-file in a text-editor to edit it to the correct command line syntax manually, but when reloading the project with xcode, it auto changes the syntax into interpreting the parameter to force_load as a separate flag. Anyone having an idea on this issue? Thx, Kaiserludi.

  Read the article

• Socket.Recieve Failing When Multithreaded

  - by Qua

  The following piece of code runs fine when parallelized to 4-5 threads, but starts to fail as the number of threads increase somewhere beyond 10 concurrentthreads int totalRecieved = 0; int recieved; StringBuilder contentSB = new StringBuilder(4000); while ((recieved = socket.Receive(buffer, SocketFlags.None)) > 0) { contentSB.Append(Encoding.ASCII.GetString(buffer, 0, recieved)); totalRecieved += recieved; } The Recieve method returns with zero bytes read, and if I continue calling the recieve method then I eventually get a 'An established connection was aborted by the software in your host machine'-exception. So I'm assuming that the host actually sent data and then closed the connection, but for some reason I never recieved it. I'm curious as to why this problem arises when there are a lot of threads. I'm thinking it must have something to do with the fact that each thread doesn't get as much execution time and therefore there are some idle time for the threads which causes this error. Just can't figure out why idle time would cause the socket not to recieve any data.

  Read the article

• Advice needed: cold backup for SQL Server 2008 Express?

  - by Mikey Cee

  What are my options for achieving a cold backup server for SQL Server Express instance running a single database? I have an SQL Server 2008 Express instance in production that currently represents a single point of failure for my application. I have a second physical box sitting at the installation that is currently doing nothing. I want to somehow replicate my database in near real time (a little bit of data loss is acceptable) to the second box. The database is very small and resources are utilized very lightly. In the case that the production server dies, I would manually reconfigure my application to point to the backup server instead. Although Express doesn't support log shipping, I am thinking that I could manually script a poor man's version of it, where I use batch files to take the logs and copy them across the network and apply them to the second server at 5 minute intervals. Does anyone have any advice on whether this is technically achievable, or if there is a better way to do what I am trying to do? Note that I want to avoid having to pay for the full version of SQL Server and configure mirroring as I think it is an overkill for this application. I understand that other DB platforms may present suitable options (eg. a MySQL Cluster), but for the purposes of this discussion, let's assume we have to stick to SQL Server.

  Read the article

• Checking if Date is within Range

  - by Brett Powell

  So I am using a scripting language with c++ syntax, and trying to think of the best way to check if a date is within range. The problem I am running into is that if the current day is in a new month, the check is failing. Here is what my code looks like... if(iMonth >= iStartMonth && iMonth <= iEndMonth) { if(iDay >= iStartDay && iDay <= iEndDay) { if(iYear >= iStartYear && iYear <= iEndYear) { bEnabled = true; return; When I have something like this... (Pulled in from cfg file specified by client) Start date: 3 27 2010 End Date: 4 15 2010 Current Date: 3 31 2010 The day check fails because if(iDay <= iEndDay) does not pass. The scripting language doesn't have a lot of time related functions, and I cant compare timestamps because im allowing users to put like "03:27:2010" and "04:15:2010" as start/end dates in a config file. Im assuming I am just not thinking straight and missing an easy fix.

  Read the article

• looking to streamline my RSS feed mashup

  - by Mark Cejas

  Hello crafty developers, I have aggregated RSS feeds from various sources with RSSowl, fetching directly from the social mention API. The RSS feeds are categorized into the following major categories: blogs, news, twitter, Q&A and social networking sites. Each major category is nested with a common group of RSS feeds that represent a particular client/brand ontology. Merging these feeds into the RSSowl reader application, allows me to conduct and save refined search queries (from the aggregated data) into a single file - that I can then tag and further segment for analysis. This scheme is utilized for my own research needs and has helped me considerably. However, I find this RSS mashup scheme kinda clumsy, it requires quite a bit of time to initially organize all of the feeds and I would like to be able to do further natural language processing to the data as well as eventually be able to rank the collected list of URL's into some order of media prominence - right I don't want to pay the ridiculous radian6 web analytics fees, when my intuition is telling me that with a bit of 'elbow grease' I can maybe leverage some available resources online to develop a functional low scale web mining application and get some good intelligence from it. I am now starting to learn a little about computer science - my background is in physical science/statistics so is my thinking in the right track? So, I guess I am imagining an application that allows me to query in a refined manner. A manner that allows me to search for keyword combinations, applying AND/OR operators, selectively focus my queries into particular sources - like a collection of blogs or twitter, or social networking communities, then save the results of my queries into a structured format that can then be manipulated and explored. Am I dreaming? I just had to get all of this out. any bit of advice and insight would be hugely appreciated. my best, Mark

  Read the article

• SQLAlchemy: who is in charge of the "session"? ( and how to unit-test with sessions )

  - by Nick Perkins

  I need some guidance on how to use session objects with SQLAlchemy, and how to organize Unit Tests of my mapped objects. What I would like to able to do is something like this: thing = BigThing() # mapped object child = thing.new_child() # create and return a related object thing.save() # will also save the child object In order to achieve this, I was thinking of having the BigThing actually add itself ( and it's children ) to the database -- but maybe this not a good idea? One reason to add objects as soon as possible is Automatic id values that are assigned by the database -- the sooner they are available, the fewer problems there are ( right? ) What is the best way to manage session objects? Who is in charge of the session? Should it be created only when required? or saved for a long time? What about Unit Tests for my mapped objects?...how should the session be handled? Is it ever OK to have mapped objects just automatically add themselves to a database? or is that going to lead to trouble?

  Read the article

• Delaying LINQ to SQL Select Query Execution

  - by Maxim Z.

  I'm building an ASP.NET MVC site that uses LINQ to SQL. In my search method that has some required and some optional parameters, I want to build a LINQ query while testing for the existence of those optional parameters. Here's what I'm currently thinking: using(var db = new DBDataContext()) { IQueryable<Listing> query = null; //Handle required parameter query = db.Listings.Where(l => l.Lat >= form.bounds.extent1.latitude && l.Lat <= form.bounds.extent2.latitude); //Handle optional parameter if (numStars != null) query = query.Where(l => l.Stars == (int)numStars); //Other parameters... //Execute query (does this happen here?) var result = query.ToList(); //Process query... Will this implementation "bundle" the where clauses and then execute the bundled query? If not, how should I implement this feature? Also, is there anything else that I can improve? Thanks in advance.

  Read the article

• how to implement enhanced session handling in PHP

  - by praksant

  Hi, i'm working with sessions in PHP, and i have different applications on single domain. Problem is, that cookies are domain specific, and so session ids are sent to any page on single domain. (i don't know if there is a way to make cookies work in different way). So Session variables are visible in every page on this domain. I'm trying to implement custom session manager to overcome this behavior, but i'm not sure if i'm thinking about it right. I want to completely avoid PHP session system, and make a global object, which would store session data and on the end of script save it to database. On first access i would generate unique session_id and create a cookie On the end of script save session data with session_id, timestamps for start of session and last access, and data from $_SERVER, such as REMOTE_ADDR, REMOTE_PORT, HTTP_USER_AGENT. On every access chceck database for session_id sent in cookie from client, check IP, Port and user agent (for security) and read data into session variable (if not expired). If session_id expired, delete from database. That session variable would be implemented as singleton (i know i would get tight coupling with this class, but i don't know about better solution). I'm trying to get following benefits: Session variables invisible in another scripts on the same server and same domain Custom management of session expiration Way to see open sessions (something like list of online users) i'm not sure if i'm overlooking any disadvantages of this solution. Is there any better way? Thank you!!

  Read the article

• Powershell finding services using a cmdlet dll

  - by bartonm

  I need to upgrade a dll assemblies, written in C#, in our installation. Before I replace the DLL file, I want to check if the file has a lock and if so display a message. How do I implement this in powershell? I was thinking iterate through Get-Process checking dependencies. Solved. I iterated through list looking a file path match. function IsCaradigmPowershellDLLFree() { # The list of DLLs to check for locks by running processes. $DllsToCheckForLocks = "$env:ProgramFiles\Caradigm Platform\System 3.0\Platform\PowerShell\Caradigm.Platform.Powershell.dll", "$env:ProgramFiles\Caradigm Platform\System 3.0\Platform\PowerShell\Caradigm.Platform.Powershell.InternalPlatformSetup.dll"; # Assume true, then check all process dependencies $result = $true; # Iterate through each process and check module dependencies foreach ($p in Get-Process) { # Iterate through each dll used in a given process foreach ($m in Get-Process -Name $p.ProcessName -Module -ErrorAction SilentlyContinue) { # Check if dll dependency match any DLLs in list foreach ($dll in $DllsToCheckForLocks) { # Compare the fully-qualified file paths, # if there's a match then a lock exists. if ( ($m.FileName.CompareTo($dll) -eq 0) ) { $pName = $p.ProcessName.ToString() Write-Error "$dll is locked by $pName. This dll must be have zero locked prior to upgrade. Stop this service to release this lock on $m1." $result = $false; } } } } return $result; }

  Read the article

• JDBC call not executing

  - by dbyrne

  I am working on one of the DAOs for a medium sized web application. Unfortunately, it contains very convoluted logic, and makes hundreds of JDBC stored proc calls in loops. This is out of my control. I am working on a method inside the DAO which makes a single JDBC call. The simplified version of what this method looks like is this: DriverManager.registerDriver(new com.sybase.jdbc2.jdbc.SybDriver()); Connection con = DriverManager.getConnection((String)connectionDetails.get("DATABASE_URL") (String)connectionDetails.get("USERID"), (String)connectionDetails.get("PASSWORD")); String sqlToExecute = "{call " + STORED_PROC + "(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)}"; CallableStatement stmt = con.prepareCall(sqlToExecute); //Maybe I should try calling clearParameters here? stmt.setString(1,someData); //....Set of parameters.... if (!stmt.execute()) { //execute method never returns false } stmt.close(); Its pretty much a textbook JDBC call. All this stored proc does is insert a single row. Here is where things get crazy: This code works when you run it through a debugger line by line, but fails when you run it "full speed". Not only does it fail, but it doesn't throw any exception! The execute method always returns true. It just breezes right through the JDBC call without inserting a row to the database. If you go through the log files, copy the stored proc call and run it manually, it works (just like it does in debug mode). Whats strange is that the rest of the DAO, with all its hundreds of looped stored proc calls, works fine. My thinking is that Connection or CallableStatement is caching some value behind the scenes that is screwing things up. Has anyone ever seen anything like this before? A JDBC call failing with no exceptions? I know it will be impossible to provide a complete solution to this without seeing the whole application, I am just looking for suggestions on possible issues to investigate.

  Read the article

• Visual studio feature - commenting code Ctrl K - Ctrl C

  - by Michael

  I commented on this answer some time ago regarding how visual studio comments out code with // or /* */. I was thinking to revise the answer (to include my findings) but I had to test it first, which kind of confused me. My finding is that depending on where your marker is when you press Ctrl - K, Ctrl - C you will get either // or /* */. So I tried it out on the following code: [1] [2]FD_ZERO(&mFSet); FD_SET(user->mSender, &mFSet); timeval zeroTime = { 0, 0 }; int sel = select(0, NULL, &mFSet, NULL, &zeroTime); [3] if (sel == SOCKET_ERROR){ [5]return false; [4] } if (sel == 0){ [6] return false; [7] } The [x] is markerpositions. All [1] positions give // for all marked lines. However Start position End Position: gives: [2] [3] : /* */ [2] [4] : // [2] [5] : /* */ [2] [more than 5] : // [5] [6] : /* */ [5] [7] : // I guess it has to do with forward indentation (not backwards), that whenever code is indented more than the starting line you get // except when you haven't selected any text on the indented line ([2] [5]). But why the distinction? Why not use /* */ for when you start at [2] and // when you start at [1]?

  Read the article

• Editing a remote file on-the-fly with PHP

  - by user275074

  Hi, I have a requirement to edit a remote text file on-the-fly, the content of which currently stands at ~1Mb. I have tried a couple of approaches and both seem to be clunky or hog memory which I can't rely on. Thinking out logically what I'm trying to achieve is: FTP to a remote server. Download a copy of the file for backup purposes and store it somewhere locally. Open the remote file and add the necessary lines required. Remove lines from the remote file as per an array of un-required data generated from the local server. Is this possible? I've managed to code steps 1 and 2 but I'm having difficult with 3 and 4. The way I'm doing it now is to use fgets and return the whole string. Really, I don't want to do this as it involves manipulating and re-generating the whole string (and it's large) and then re-inserting it in between two markers in the remote file. Is there no way of manipulating the lines of text in the file on-the-fly?

  Read the article

• How to find an embedded platform?

  - by gmagana

  I am new to the locating hardware side of embedded programming and so after being completely overwhelmed with all the choices out there (pc104, custom boards, a zillion option for each board, volume discounts, devel kits, ahhh!!) I am asking here for some direction. Basically, I must find a new motherboard and (most likely) re-implement the program logic. Rewriting this in C/C++/Java/C#/Pascal/BASIC is not a problem for me. so my real problem is finding the hardware. This motherboard will have several other devices attached to it. Here is a summary of what I need to do: Required: 2 RS232 serial ports (one used all the time for primary UI, the second one not continuous) 1 modem (9600+ baud ok) [Modem will be in simultaneous use with only one of the serial port devices, so interrupt sharing with one serial port is OK, but not both] Minimum permanent/long term storage: Whatever O/S requires + 1 MB (executable) + 512 KB (Data files) RAM: Minimal, whatever the O/S requires plus maybe 1MB for executable. Nice to have: USB port(s) Ethernet network port Wireless network Implementation languages (any O/S I will adapt to): First choice Java/C# (Mono ok) Second choice is C/Pascal Third is BASIC Ok, given all this, I am having a lot of trouble finding hardware that will support this that is low in cost. Every manufacturer site I visit has a lot of options, and it's difficult to see if their offering will even satisfy my must-have requirements (for example they sometimes list 3 "serial ports", but it appears that only one of the three is RS232, for example, and don't mention what the other two are). The #1 constraint is cost, #2 is size. Can anyone help me with this? This little task has left me thinking I should have gone for EE and not CS :-). EDIT: A bit of background: This is a system currently in production, but the original programmer passed away, and the current hardware manufacturer cannot find hardware to run the (currently) DOS system, so I need to reimplement this in a modern platform. I can only change the programming and the motherboard hardware.

  Read the article

• Which languages and techniques can I use to improve my coding practices?

  - by Danjah

  I've been offered the opportunity upskill through study, while at work which is great. My background I am mostly self-taught, but have worked with many excellent people over the years - both self-taught and fully educated, and on many decent projects. I have mild experience in Actionscript, I'm getting better every day with my Javascript, and my CSS is angled at best practice, but needs a bit of modernising. I'm a traditional interface developer, I'm not stupid and I like a challenge. My goal I need to start seeing ways of applying better logic, optimising code, refactoring, different styles of development (agile, others?), and.. well I need to try and start thinking like.. a more solid programmer. Its hard to describe, I have good solutions and I'm efficient - but I KNOW that there's a bunch I am missing. I am already employed with a solid career, but I feel the need to fill gaps. My question/s Are there a set of guiding principles you can recommend I focus on to improve the points above? Are there particular programming languages which I might focus on to get a broader overview? Do you think I should avoid particular styles of development, or even languages, while solidifying what might end up being part 'the basics' but hopefully 'advanced programming'? -- Sorry if this appears off topic or something but I figure you're probably some of the best people to ask.

  Read the article

• Design patterns for Agent / Actor based concurrent design.

  - by nso1

  Recently i have been getting into alternative languages that support an actor/agent/shared nothing architecture - ie. scala, clojure etc (clojure also supports shared state). So far most of the documentation that I have read focus around the intro level. What I am looking for is more advanced documentation along the gang of four but instead shared nothing based. Why ? It helps to grok the change in design thinking. Simple examples are easy, but in a real world java application (single threaded) you can have object graphs with 1000's of members with complex relationships. But with agent based concurrency development it introduces a whole new set of ideas to comprehend when designing large systems. ie. Agent granularity - how much state should one agent manage - implications on performance etc or are their good patterns for mapping shared state object graphs to agent based system. tips on mapping domain models to design. Discussions not on the technology but more on how to BEST use the technology in design (real world "complex" examples would be great).

  Read the article

• How to use keyword this in a mouse wrapper in right context in Javascript?

  - by MartyIX

  Hi, I'm trying to write a simple wrapper for mouse behaviour. This is my current code: function MouseWrapper() { this.mouseDown = 0; this.OnMouseDownEvent = null; this.OnMouseUpEvent = null; document.body.onmousedown = this.OnMouseDown; document.body.onmouseup = this.OnMouseUp; } MouseWrapper.prototype.Subscribe = function (eventName, fn) { // Subscribe a function to the event if (eventName == 'MouseDown') { this.OnMouseDownEvent = fn; } else if (eventName == 'MouseUp') { this.OnMouseUpEvent = fn; } else { alert('Subscribe: Unknown event.'); } } MouseWrapper.prototype.OnMouseDown = function () { this.mouseDown = 1; // Fire event $.dump(this.OnMouseDownEvent); if (this.OnMouseDownEvent != null) { alert('test'); this.OnMouseDownEvent(); } } MouseWrapper.prototype.OnMouseUp = function () { this.mouseDown = 0; // Fire event if (this.OnMouseUpEvent != null) { this.OnMouseUpEvent(); } } From what I gathered it seems that in MouseWrapper.prototype.OnMouseUp and MouseWrapper.prototype.OnMouseDown the keyword "this" doesn't mean current instance of MouseWrapper but something else. And it makes sense that it doesn't point to my instance but how to solve the problem? I want to solve the problem properly I don't want to use something dirty. My thinking: * use a singleton pattern (mouse is only one after all) * pass somehow my instance to OnMouseDown/Up - how? Thank you for help!

  Read the article

• Dangers when deploying Flash/Flex UI test automation hooks to production?

  - by Merlyn Morgan-Graham

  I am interested in doing automated testing against a Flex based UI. I have found out that my best options for UI automation (due to being C# controllable, good licensing conditions, etc) all seem to require that I compile test hooks into my application. Because of this, I am thinking of recommending that these hooks be compiled into our build. I have found a few places on the net that recommend not deploying bits with this instrumentation enabled, and I'd like to know why. Is it a performance drain, or a security risk? If it is a security risk, can you explain how the attack surface is increased? I am not a Flash or Flex developer, though I have some experience with threat modeling. For reference, here's the tools I'm specifically considering: QTP Selenium-Flex API I am having problems finding all the warnings/suggestions I found last night, but here's an example that I can find: http://www.riatest.com/products/getting-started.html Warning! Automation enabled applications expose all properties of all GUI components. This makes them vulnerable to malicious use. Never make automation enabled application publicly available. Always restrict access to such applications and to RIATest Loader to trusted users only. Related question (how to do conditional compilation to insert/remove those hooks): Conditionally including Flex libraries (SWCs) in mxmlc/compc ant tasks

  Read the article

• Subset and lagging list data structure R

  - by user1234440

  I have a list that is indexed like the following: >list.stuff [[1]] [[1]]$vector ... [[1]]$matrix .... [[1]]$vector [[2]] null [[3]] [[3]]$vector ... [[3]]$matrix .... [[3]]$vector . . . Each segment in the list is indexed according to another vector of indexes: >index.list 1, 3, 5, 10, 15 In list.stuff, only at each of the indexes 1,3,5,10,15 will there be 2 vectors and one matrix; everything else will be null like [[2]]. What I want to do is to lag like the lag.xts function so that whatever is stored in [[1]] will be pushed to [[3]] and the last one drops off. This also requires subsetting the list, if its possible. I was wondering if there exists some functions that handle list manipulation. My thinking is that for xts, a time series can be extracted based on an index you supply: xts.object[index,] #returns the rows 1,3,5,10,15 From here I can lag it with: lag.xts(xts.object[index,]) Any help would be appreciated thanks: EDIT: Here is a reproducible example: list.stuff<-list() vec<-c(1,2,3,4,5,6,7,8,9) vec2<-c(1,2,3,4,5,6,7,8,9) mat<-matrix(c(1,2,3,4,5,6,7,8),4,2) list.vec.mat<-list(vec=vec,mat=mat,vec2=vec2) ind<-c(2,4,6,8,10) for(i in ind){ list.stuff[[i]]<-list.vec.mat }

  Read the article

• [jscript] Good (better) substition for setInterval or setTimeout

  - by riffnl

  I've got a masterpage with some nice UI (jQuery) features. One of these options is interefering with my embedded YouTube (or other alike-) objects. On each, in this case, setInterval event the embedded video stops displaying new frames (for like a second). More detail: I've got a "polaroid" gallery (in the header) with only 5 100x100 images in it (test: preloading has no effect on performance) and my gallery will show or hide them (fade-in / fade-out) after a period of time. (test: non-animated display:hide or display:block has no effect on performance). After some testing and I've come to the conclusion that it isn't the "animated" showing or hiding of the pictures, but it's the interval itself (- since altering to display:hide or block had the same result). Perhaps it is my "gallery" "function" on itself ... function poladroid() { if (!galleryHasFocus) { if (galleryMax >= 0) { galleryCurrent++; if (galleryCurrent > galleryMax) { galleryCurrent = 0; showPictures = !showPictures; } if (showPictures) { $('#pic-' + galleryCurrent.toString()).show("slow"); } else { $('#pic-' + galleryCurrent.toString()).hide("slow"); } } } if (!intervalSet) { window.setInterval("poladroid()", 3000); intervalSet = true; } } It's not like my function is doing really awkward stuff is it? So, I was thinking I needed a more "loose" interval function.. but is there an option for it?

  Read the article

• A GUID as the MySQL table's Primary Key or as a separate column

  - by Ben

  I have a multi-process program that performs, in a 2 hour period, 5-10 million inserts to a 34GB table within a single Master/Slave MySQL setup (plus an equal number of reads in that period). The table in question has only 5 fields and 3 (single field) indexes. The primary key is auto-incrementing. I am far from a DBA, but the database appears to be crippled during this two hour period. So, I have a couple of general questions. 1) How much bang will I get out of batching these writes into units of 10? Currently, I am writing each insert serially because, after writing, I immediately need to know, in my program, the resulting primary key of each insert. The PK is the only unique field presently and approximating the order of insertion with something like a Datetime field or a multi-column value is not acceptable. If I perform a bulk insert, I won't know these IDs, which is a problem. So, I've been thinking about turning the auto-increment primary key into a GUID and enforcing uniqueness. I've also been kicking around the idea of creating a new column just for the purposes of the GUID. I don't really see the what that achieves though, that the PK approach doesn't already offer. As far as I can tell, the big downside to making the PK a randomly generated number is that the index would take a long time to update on each insert (since insertion order would not be sequential). Is that an acceptable approach for a table that is taking this number of writes? Thanks, Ben

  Read the article

• Which design pattern is most appropriate?

  - by Anon

  Hello, I want to create a class that can use one of four algorithms (and the algorithm to use is only known at run-time). I was thinking that the Strategy design pattern sounds appropriate, but my problem is that each algorithm requires slightly different parameters. Would it be a bad design to use strategy, but pass in the relevant parameters into the constructor?. Here is an example (for simplicity, let's say there are only two possible algorithms) ... class Foo { private: // At run-time the correct algorithm is used, e.g. a = new Algorithm1(1); AlgorithmInterface* a; }; class AlgorithmInterface { public: virtual void DoSomething = 0; }; class Algorithm1 : public AlgorithmInterface { public: Algorithm1( int i ) : value(i) {} virtual void DoSomething(){ // Does something with int value }; int value; }; class Algorithm2 : public AlgorithmInterface { public: Algorithm2( bool b ) : value(b) {} virtual void DoSomething(){ // Do something with bool value }; bool value; };

  Read the article

• SSRS How to access the current value within a list control?

  - by Dale Burrell

  In SQL Server Reporting Services I have a report which has a list control which groups on currency. Within the list control I display the detailed rows of all records filtered to those with a value = £500. i.e. the top earners. However for each row I need to calculate the percentage of its amount over the total of the entire dataset. Because I am filtering it I can't use Sum(Fields!Amount.Value) as that only sums the data after filtering, so I am trying a conditional sum over the entire dataset, but am struggling with the correct condition e.g =100.00*Fields!Amount.Value/Sum((IIf(Fields!Currency.Value = "£", Fields!Amount.Value, CDec(0))),"DataSet") So where the hardcoded currency symbol is I need to access the current value of currency for the list control, but because my sum is scoped at dataset level any field access is dataset level. Ideally I'd like something like the following, otherwise any other ideas on how to solve this problem. =100.00*Fields!Amount.Value/Sum((IIf(Fields!Currency.Value = myListControl.Value, Fields!Amount.Value, CDec(0))),"DataSet") In fact, thinking about it, it would work if I just could access the row level data at that point, but how to do that when its at dataset scope within the sum statement? Hope that makes sense, any help appreciated.

  Read the article

< Previous Page | 380 381 382 383 384 385 386 387 388 389 390 391  | Next Page >