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• Populating PDF Fields using FDFACX

  - by NWilliams

  I was recently asked to preform some updates to an existing PDF document. The changes required were completed using Adobe Designer (the only tool I have available to me). These changes included alignment, and new text. Note that there were fillable form fields on the forms, and they were left untouched. The saved version of the form was then put into our ASP.NET application, which pre-populates the form fields were applicable (things like name, address etc... things we have in our database). For some reason, the new form does not populate. I've confirmed that the form fields have the correct names, that the actual file (the pdf) that is being pre-populated has the same permissions as others that are working. There are no errors thrown, and no difference in a step through with a working form and a non-working form. This is a legacy project and I have no real experience with the PDF populator they are using ... FDFACX .NET? And can't find a lot of info on it online. Any ideas?

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• Valid javascript object property names

  - by hawkettc

  I'm trying to work out what is considered valid for the property name of a javascript object. For example var b = {} b['-^colour'] = "blue"; // Works fine in Firefox, Chrome, Safari b['colour'] = "green"; // Ditto alert(b['-^colour']); // Ditto alert(b.colour); // Ditto for(prop in b) alert(prop); // Ditto //alert(b.-^colour); // Fails (expected) This post details valid javascript variable names, and '-^colour' is clearly not valid (as a variable name). Does the same apply to object property names? Looking at the above I'm trying to work out if b['-^colour'] is invalid, but works in all browsers by quirk, and I shouldn't trust it to work going forward b['-^colour'] is completely valid, but it's just of a form that can only be accessed in this manner - (it's supported so Objects can be used as maps perhaps?) Something else As an aside, a global variable in javascript might be declared at the top level as var abc = 0; but could also be created (as I understand it) with window['abc'] = 0; the following works in all the above browsers window['@£$%'] = "bling!"; alert(window['@£$%']); Is this valid? It seems to contradict the variable naming rules - or am I not declaring a variable there? What's the difference between a variable and an object property name? Cheers, Colin

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• PHP: Opening/closing tags & performance?

  - by Tom

  Hi, This may be a silly question, but as someone relatively new to PHP, I'm wondering if there are any performance-related issues to frequently opening and closing PHP tags in HTML template code, and if so, what might be best practices in terms of working with php tags? My question is not about the importance/correctness of closing tags, or about which type of code is more readable than another, but rather about how the document gets parsed/executed and what impact it might have on performance. To illustrate, consider the following two extremes: Mixing PHP and HTML tags: <?php echo '<tr> <td>'.$variable1.'</td> <td>'.$variable2.'</td> <td>'.$variable3.'</td> <td>'.$variable4.'</td> <td>'.$variable5.'</td> </tr>' ?> // PHP tag opened once Separating PHP and HTML tags: <tr> <td><?php echo $variable1 ?></td> <td><?php echo $variable2 ?></td> <td><?php echo $variable3 ?></td> <td><?php echo $variable4 ?></td> <td><?php echo $variable5 ?></td> </tr> // PHP tag opened five times Would be interested in hearing some views on this, even if it's just to hear that it makes no difference. Thanks.

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• Does Function pointer make the program slow?

  - by drigoSkalWalker

  Hi guys. I read about function pointers in C And everyone said that will make my program run slow. Is it true? I made a program to check it. And I got the same results on both cases. (mesure the time.) So, is it bad to use fuction pointer? Thanks in advance. To response for some guys. I said 'run slow' for the time that I have compared on a loop. like this. int end = 1000; int i = 0; while (i < end) { fp = func; fp (); } When you execute this, i got the same time if I execute this. while (i < end) { func (); } So I think that function pointer have no difference of time and it don't make a program run slow as many people said.

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• Faster Insertion of Records into a Table with SQLAlchemy

  - by Kyle Brandt

  I am parsing a log and inserting it into either MySQL or SQLite using SQLAlchemy and Python. Right now I open a connection to the DB, and as I loop over each line, I insert it after it is parsed (This is just one big table right now, not very experienced with SQL). I then close the connection when the loop is done. The summarized code is: log_table = schema.Table('log_table', metadata, schema.Column('id', types.Integer, primary_key=True), schema.Column('time', types.DateTime), schema.Column('ip', types.String(length=15)) .... engine = create_engine(...) metadata.bind = engine connection = engine.connect() .... for line in file_to_parse: m = line_regex.match(line) if m: fields = m.groupdict() pythonified = pythoninfy_log(fields) #Turn them into ints, datatimes, etc if use_sql: ins = log_table.insert(values=pythonified) connection.execute(ins) parsed += 1 My two questions are: Is there a way to speed up the inserts within this basic framework? Maybe have a Queue of inserts and some insertion threads, some sort of bulk inserts, etc? When I used MySQL, for about ~1.2 million records the insert time was 15 minutes. With SQLite, the insert time was a little over an hour. Does that time difference between the db engines seem about right, or does it mean I am doing something very wrong?

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• Make password case unsensitive in shared ASP.Net membership tables web ap

  - by bill

  Hi all, i have two webapps.. that share ASP.Net membership tables. Everything works fine except i cannot remove case-sensitivity in one of the apps the way i am doing it in the other. in the non-working app void Login1_LoggingIn(object sender, LoginCancelEventArgs e) { string username = Login1.UserName.Trim(); if (!string.IsNullOrEmpty(username)) { MembershipUser user = Membership.GetUser(username); if (user != null) { // Only adjust the UserName if the password is correct. This is more secure // so a hacker can't find valid usernames if we adjust the case of mis-cased // usernames with incorrect passwords. string password = Login1.Password.ToUpper(); if (Membership.ValidateUser(user.UserName, password)) { Login1.UserName = user.UserName; } } } } is not working. the password is stored as all upper case. Converted at the time the membership user is created! So if the password is PASSWORD, typing PASSWORD allows me to authenticate. but typing password does not! Even though i can see the string being sent is PASSWORD (converted with toUpper()). I am at a complete loss on this.. in the other app i can type in lower or upper or mixed and i am able to authenticate. In the other app i am not using the textboxes from the login control though.. not sure if this is making the difference??

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• Why doesn't this CompiledQuery give a performance improvement?

  - by Grammarian

  I am trying to speed up an often used query. Using a CompiledQuery seemed to be the answer. But when I tried the compiled version, there was no difference in performance between the compiled and non-compiled versions. Can someone please tell me why using Queries.FindTradeByTradeTagCompiled is not faster than using Queries.FindTradeByTradeTag? static class Queries { // Pre-compiled query, as per http://msdn.microsoft.com/en-us/library/bb896297 private static readonly Func<MyEntities, int, IQueryable<Trade>> mCompiledFindTradeQuery = CompiledQuery.Compile<MyEntities, int, IQueryable<Trade>>( (entities, tag) => from trade in entities.TradeSet where trade.trade_tag == tag select trade); public static Trade FindTradeByTradeTagCompiled(MyEntities entities, int tag) { IQueryable<Trade> tradeQuery = mCompiledFindTradeQuery(entities, tag); return tradeQuery.FirstOrDefault(); } public static Trade FindTradeByTradeTag(MyEntities entities, int tag) { IQueryable<Trade> tradeQuery = from trade in entities.TradeSet where trade.trade_tag == tag select trade; return tradeQuery.FirstOrDefault(); } }

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• What is a mantainable way of saving "star rating" in a database?

  - by Montecristo

  I'll use the jQuery plugin for presenting the user with a nice interface The request is to display 5 stars, up to a total score of 10 (2 points per star). By now I thought about using 7/10 as a format for that value, but what if at some point in the future I'll receive a request like We would like to give users more choice, let's increase the total score to 20 (so that each star contributes with a maximum of 4 points) I'll end up with a table with mixed values for the "star rating" column: some will be like 7/10 while others will be like 14/20. Is it ok for you to have this difference in the database and deal with it in the logic layer to have it consistent? Or is preferred another way so that querying the table will not result in inconsistent results outside the application? Maybe floating point values could help me, is it better to store that value as a number less than or equal to one? So in each of the two examples the resulting value stored in the database would be 0,7, as a number, not a varchar, which can be queried also outside the application. What do you think?

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• how to programatically compare permissions of login/user in sql server 2005

  - by titanium

  There's a login/user in SQL Server who is having a problem importing accounts in production server. I don't have an idea what method he is doing this. According to the one importing, this import is working fine in development server. But when he did the same import in production it is giving him errors. Below are the errors he is getting for each accounts. 2009-06-05 18:01:05.8254 ERROR [engine-1038] Task [1038:00001 - Members]: Step 1.0 [<Insert step description>]: Task.RunStep(): StoreRow has failed 2009-06-05 18:01:05.9035 ERROR [engine-1038] Task [1038:00001 - Members]: Step 1.0 [<Insert step description>]: Task.RunStep(): StoreRow exception: Exception caught while storing Data. [Microsoft][ODBC SQL Server Driver][SQL Server]'ACCOUNT1' is not a valid login or you do not have permission. Please note that 'ACCOUNT1' is not the real account name. I just changed it for security reason. Using SQL Server Management Studio (SSMS), I viewed/checked the permissions of the user/login who is performing the import from development server and production for comparison. I found no difference. My question is: Is there a way to programmatically query permissions in server and database level of a particular login/user so I can compare/contrast for any differences?

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• Cost of logic in a query

  - by FrustratedWithFormsDesigner

  I have a query that looks something like this: select xmlelement("rootNode", (case when XH.ID is not null then xmlelement("xhID", XH.ID) else xmlelement("xhID", xmlattributes('true' AS "xsi:nil"), XH.ID) end), (case when XH.SER_NUM is not null then xmlelement("serialNumber", XH.SER_NUM) else xmlelement("serialNumber", xmlattributes('true' AS "xsi:nil"), XH.SER_NUM) end), /*repeat this pattern for many more columns from the same table...*/ FROM XH WHERE XH.ID = 'SOMETHINGOROTHER' It's ugly and I don't like it, and it is also the slowest executing query (there are others of similar form, but much smaller and they aren't causing any major problems - yet). Maintenance is relatively easy as this is mostly a generated query, but my concern now is for performance. I am wondering how much of an overhead there is for all of these case expressions. To see if there was any difference, I wrote another version of this query as: select xmlelement("rootNode", xmlforest(XH.ID, XH.SER_NUM,... (I know that this query does not produce exactly the same, thing, my plan was to move the logic to PL/SQL or XSL) I tried to get execution plans for both versions, but they are the same. I'm guessing that the logic does not get factored into the execution plan. My gut tells me the second version should execute faster, but I'd like some way to prove that (other than writing a PL/SQL test function with timing statements before and after the query and running that code over and over again to get a test sample). Is it possible to get a good idea of how much the case-when will cost? Also, I could write the case-when using the decode function instead. Would that perform better (than case-statements)?

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• Entity Framework Validation & usage

  - by kmsellers

  I'm aware there is an AssociationChanged event, however, this event fires after the association is made. There is no AssociationChanging event. So, if I want to throw an exception for some validation reason, how do I do this and get back to my original value? Also, I would like to default values for my entity based on information from other entities but do this only when I know the entitiy is instanced for insertion into the database. How do I tell the difference between that and the object getting instanced because it is about to be populated based on existing data? Am I supposed to know? Is that considiered business logic that should be outside of my entity business logic? If that's the case, then should I be designing controller classes to wrap all these entities? My concern is that if I deliver back an entity, I want the client to get access to the properties, but I want to retain tight control over validations on how they are set, defaulted, etc. Every example I've seen references context, which is outside of my enity partial class validation, right? BTW, I looked at the EFPocoAdapter and for the life of me cannot determine how to populate lists of from within my POCO class... anyone know how I get to the context from a EFPoco Class?

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• Inline function v. Macro in C -- What's the Overhead (Memory/Speed)?

  - by Jason R. Mick

  I searched Stack Overflow for the pros/cons of function-like macros v. inline functions. I found the following discussion: Pros and Cons of Different macro function / inline methods in C ...but it didn't answer my primary burning question. Namely, what is the overhead in c of using a macro function (with variables, possibly other function calls) v. an inline function, in terms of memory usage and execution speed? Are there any compiler-dependent differences in overhead? I have both icc and gcc at my disposal. My code snippet I'm modularizing is: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = AttractiveTerm * AttractiveTerm; EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); My reason for turning it into an inline function/macro is so I can drop it into a c file and then conditionally compile other similar, but slightly different functions/macros. e.g.: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = pow(SigmaSquared/RadialDistanceSquared,9); EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); (note the difference in the second line...) This function is a central one to my code and gets called thousands of times per step in my program and my program performs millions of steps. Thus I want to have the LEAST overhead possible, hence why I'm wasting time worrying about the overhead of inlining v. transforming the code into a macro. Based on the prior discussion I already realize other pros/cons (type independence and resulting errors from that) of macros... but what I want to know most, and don't currently know is the PERFORMANCE. I know some of you C veterans will have some great insight for me!!

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• Python coin-toss

  - by Andy

  i am new to Python, and i can't wrap my head around this. I have following function defined: def FlipCoins(num_flips): heads_rounds_won = 0 for i in range(10000): heads = 0 tails = 0 for j in range(num_flips): dice = random.randint(0,1) if dice==1: heads += 1 else: tails += 1 if heads > tails: heads_rounds_won += 1 return heads_rounds_won Here is what it should do (but apparently doesn't): flip a coin num_flip times, count heads and tails, and see if there are more heads than tails. If yes, increment head_rounds_won by 1. Repeat 10000 times. I would assume that head_rounds_won will approximate 5000 (50%). And it does that for odd numbers as input. For example, 3, 5 or 7 will produce about 50%. However, even numbers will produce much lower results, more like 34%. Small numbers especially, with higher even numbers, like for example 800, the difference to 50% is much narrower. Why is this the case? Shouldn't any input produce about 50% heads/tails?

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• How to find every possible combination of an arbitrary number of arrays in PHP

  - by Travis

  I have an arbitrary number of nested arrays in php. For example: Array ( [0] => Array ( [0] => 36 [0] => 2 [0] => 9 ) [1] => Array ( [0] => 95 [1] => 21 [2] => 102 [3] => 38 ) [2] => Array ( [0] => 3 [1] => 5 ) ) I want to find the most efficient way to combine all possible combinations of each of these nested arrays. I'd like to end up with something that looks like this... Array ( [0] => "36,95,3" [1] => "36,95,5" [2] => "36,21,3" [3] => "36,21,5" etc... ) The order the results are combined in is not important. That is to say, there is no difference between "3,95,36", "36,95,3", and "95,36,3". I would like to omit these redundant combinations. Any suggestions on how to go about this would be much appreciated. Thanks in advance,

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• Where are possible locations of queueing/buffering delays in Linux multicast?

  - by Matt

  We make heavy use of multicasting messaging across many Linux servers on a LAN. We are seeing a lot of delays. We basically send an enormous number of small packages. We are more concerned with latency than throughput. The machines are all modern, multi-core (at least four, generally eight, 16 if you count hyperthreading) machines, always with a load of 2.0 or less, usually with a load less than 1.0. The networking hardware is also under 50% capacity. The delays we see look like queueing delays: the packets will quickly start increasing in latency, until it looks like they jam up, then return back to normal. The messaging structure is basically this: in the "sending thread", pull messages from a queue, add a timestamp (using gettimeofday()), then call send(). The receiving program receives the message, timestamps the receive time, and pushes it in a queue. In a separate thread, the queue is processed, analyzing the difference between sending and receiving timestamps. (Note that our internal queues are not part of the problem, since the timestamps are added outside of our internal queuing.) We don't really know where to start looking for an answer to this problem. We're not familiar with Linux internals. Our suspicion is that the kernel is queuing or buffering the packets, either on the send side or the receive side (or both). But we don't know how to track this down and trace it. For what it's worth, we're using CentOS 4.x (RHEL kernel 2.6.9).

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• SQL Compact performance on device

  - by Ben M

  My SQL Compact database is very simple, with just three tables and a single index on one of the tables (the table with 200k rows; the other two have less than a hundred each). The first time the .sdf file is used by my Compact Framework application on the target Windows Mobile device, the system hangs for well over a minute while "something" is done to the database: when deployed, the DB is 17 megabytes, and after this first usage, it balloons to 24 megs. All subsequent usage is pretty fast, so I'm assuming there's some sort of initialization / index building going on during this first usage. I'd rather not subject the user to this delay, so I'm wondering what this initialization process is and whether it can be performed before deployment. For now, I've copied the "initialized" database back to my desktop for use in the setup project, but I'd really like to have a better answer / solution. I've tried "full compact / repair" in the VS Database Properties dialog, but this made no difference. Any ideas? For the record, I should add that the database is only read from by the device application -- no modifications are made by that code.

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• JSON onFailure issue

  - by Mikey1980

  I’m having trouble getting a AJAX/JSON function to work correctly. I had this function grabbing value from a drop down box but now I want to use an anchor tag to set it's value. I thought it would be easy to just use the onClick event to pass string to the function I was using for the drop down box but I get the alert in JSON onFailure event even though data gets added to MySQL. I tried removing the alert from onFailure event but then it doesn't add the data. The drop down still continues work work fine, no alerts. (I should note that removing the alert also broke my drop down box) 1st I add an onClick event… <a href="<?php echo Settings::get('app.webroot'); ?>?view=schedule&action=questions" onmouseout="MM_swapImgRestore();" onmouseover="MM_swapImage('bre','','template/images/schedule/bre_f2.gif',1)" onclick="assignCallType('testing')";> 2nd I check main.js.php function assignCallType(type) { alert(type); new Request.JSON({ url: "ajax.php", onSuccess: function(rtndata,txt){ if (rtndata['STATUS'] != 'OK') alert('Status was not okay'); }, onFailure : function () { alert("onFailure") } }).get({ 'action': 'assignCallType', 'call_type': type }); } 3rd Ajax.php: the variable is back in PHP and values get added to MySQL but I get the Alert in the JSON onFailure event if ($_GET['action'] == "assignCallType") { if ($USER->isInsideSales()) { $call_type = $_GET['call_type']; $_SESSION['callinfo']->setCallType($call_type); $_SESSION['callinfo']->save($callid); echo json_encode(array('STATUS'=>'OK')); } else { echo json_encode(array('STATUS'=>'DENIED')); } } Any idea where I am going wrong. The only difference between this and the working drop down is how the function was called, I used onchange="assignCallType(this.value)".

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• "Ghost" values in PHP/Smarty.

  - by Kyle Sevenoaks

  I've been working on a site for a while changing the layout and skin of a webshop checkout process. I've noticed that if you go all the way through the process until the last page, then click the link to go back to the view products page, the delivery method price displays underneath the navigation buttons, until you refresh and it goes away again. I've downloaded both sourced from the browser (Chrome, but this bug applies to all browsers) and used a file difference tool to display the differences, the result being only: < error.html vs > normal.html 34c34 < <link href="gzip.php?file=167842c1496093fbcd391b41cf7b03da.css&time=1272272181" rel="Stylesheet" type="text/css"/> --- > <link href="gzip.php?file=167842c1496093fbcd391b41cf7b03da.css&time=1272272348" rel="Stylesheet" type="text/css"/> Which is just the way it zips up the CSS stylesheets. (afaik) Has anyone ever encountered such a problem, or anything similar? Normal: Error: I can't even hazard a guess as to what is causing this, at all. I've searched over Google for anything and come up with nothing. What could be causing this? The site in question is Euroworker.no. HTML @ Pastebin. Smarty snippet: {if !$CANONICAL} {canonical}{self}{/canonical} {/if} <link rel="canonical" href="{$CANONICAL}" /> <!-- Css includes --> {includeCss file="frontend/Frontend.css"} {includeCss file="backend/stat.css"} {if {isRTL}} {includeCss file="frontend/FrontendRTL.css"} {/if} {compiledCss glue=true nameMethod=hash} <!--[if lt IE 8]> <link href="stylesheet/frontend/FrontendIE.css" rel="Stylesheet" type="text/css"/> {if $ieCss} <link href="{$ieCss}" rel="Stylesheet" type="text/css"/> {/if} <![endif]--> Thanks.

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• [IE6] Cannot upload non-existent file

  - by geff_chang

  I am asking the same question as this: http://stackoverflow.com/questions/691323/trying-to-upload-a-non-existent-file-in-internet-explorer-form-is-not-submitted I'm not sure if the topic starter found a solution, since he did not post the answer. So, I'd like to ask you guys this question again. I have type=input in my form, and a submit button. If I type garbage input into the textbox (like the text "abc") in the file control's textbox, and click the submit button, the form is not submitted to the server. AND, no feedback is given to the user. Instead of this "Is-the-submit-button-broken?" behavior, is there a way I could notify the user that the file does not exist? (I am aware this is not possible, except with ActiveX, but I don't want to go into that) My client wants to hide the textbox of the file control, but I'm not sure if this is a good design. What do you guys suggest? (If it makes any difference, I am also using this jquery plugin: http://www.fyneworks.com/jquery/multiple-file-upload/)

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• Upload file using jquery dialog not working

  - by kandroid

  i want to upload file using jquery dialog. I have created a partial view and showing that partial view in the dialog. The problem is, when I directly browse the partial view and upload a file, it works perfect. BUT when I put the partial view inside a jquery dialog, it submits the form, but don't submits the file. So i have null value. I really dont understand what is the difference here!! Hope someone can help me to identify the problem. here is some codes; jquery codes: $('#UploadDialog').dialog({ autoOpen: false, width: 580, resizable: false, modal: true, open: function (event, ui) { $(this).load('@Url.Action("Upload","Notes")'); }, buttons: { "Upload": function () { $("#upload-message").html(''); $("#noteUploadForm").submit(); }, "Cancel": function () { $(this).dialog("close"); } } }); $(".uploadLink").click(function () { $('#UploadDialog').dialog('open'); }); return false; }); partial view: @using (Ajax.BeginForm("Upload", "Notes", null, new AjaxOptions { UpdateTargetId = "upload-message", InsertionMode = InsertionMode.Replace, HttpMethod = "POST", OnSuccess = "uploadSuccess" }, new { id = "noteUploadForm" , enctype="multipart/form-data"})) { <div> <div id="upload-message"></div> <div class="editLabel"> @Html.LabelFor(m => m.Notes.NoteTitle) </div> <div class="editText"> @Html.TextBoxFor(m => m.Notes.NoteTitle) </div> <div class="clear"></div> <div class="editLabel"> @Html.Label("Upload file") </div> <div class="editText"> <input type="file" name="file" />(100MB max size) </div> </div> }

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• What /else/ causes this?

  - by Mordachai

  MFC Toolbox Library.lib(SimpleFileIO.obj) : error LNK2005: _wcsnlen already defined in libcmtd.lib(wcslen_s.obj) fatal error LNK1169: one or more multiply defined symbols found This is driving me nuts. Normally, one would get this if the various projects that are a part of their solution do not agree on which CRT to use (single threaded, multi-threaded, release or debug). However, I have been over this thing about 500 times now, and they all agree. Background: this is a VS 2010 project just converted from VS 2008. MFC Toolbox Library.lib is set to compile as a static library, using /MTd, as is the target .exe I am trying to compile in this solution. Further, the solution that this is being converted from (VS 2008) already compiles & links properly!!! So it's not like that there is a disagreement between the two .vcproj's - or at least there wasn't before the conversion. Furthermore, the MFC Toolbox Library is used by about 25 other projects in another solution - and in that solution (Master Build English) it compiles & links against those other projects without complaint in both debug and release targets. I have just spent the last hour going over every single project property for this target project (Cimex Header Viewer) vs. several different target exe projects in Master Build English solution - and I cannot find a difference. They appear to be identical, excepting that they're different names. I've tried doing a clean & build all. I'm simply out of ideas. Does anyone have a thought on what else I might investigate??? I think I'm ready to start chewing glass. :(

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• Best (Java) book for understanding 'under the bonnet' for programming?

  - by Ben

  What would you say is the best book to buy to understand exactly how programming works under the hood in order to increase performance? I've coded in assembly at university, I studied computer architecture and I obviously did high level programming, but what I really dont understand is things like: -what is happening when I perform a cast -whats the difference in performance if I declare something global as opposed to local? -How does the memory layout for an ArrayList compare with a Vector or LinkedList? -Whats the overhead with pointers? -Are locks more efficient than using synchronized? -Would creating my own array using int[] be faster than using ArrayList -Advantages/disadvantages of declaring a variable volatile I have got a copy of Java Performance Tuning but it doesnt go down very low and it contains rather obvious things like suggesting a hashmap instead of using an ArrayList as you can map the keys to memory addresses etc. I want something a bit more Computer Sciencey, linking the programming language to what happens with the assembler/hardware. The reason im asking is that I have an interview coming up for a job in High Frequency Trading and everything has to be as efficient as possible, yet I cant remember every single possible efficiency saving so i'd just like to learn the fundamentals. Thanks in advance

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• Pure CSS3 show/hide full height div with transition

  - by user1898838

  Dear Stackoverflow readers, I've been breaking my head over something I've seen at Tympanus, and I can't figure out how to properly do such a thing. In this link: http://tympanus.net/Tutorials/FullscreenBookBlock/ you can see that the menu is completely hidden, and only visible when you click on an icon. It has a lovely transition, and it basically roughly sums up what I'm trying to accomplish. The only difference with the above example is that I don't want to completely hide this full-height element, and I'd like to accomplish the above effect with a hover instead of having to click a button. So in an ideal world you'd see a vertical bar, and when you hover over that bar (or click on it with your finger if you're on a tablet), it "opens up" and shows you the full content inside the opened div. Now, I can make a decent bit in html5 and css3, but the above explained effect that I'm trying to accomplish has given me serious headaches, hehe. Does anyone happen to know a tutorial I might have missed that does this exact thing? p.s.: I have tried to take apart Tympanus' html/css, but with the page-fold effect that's also implemented in it I can't seem to figure it out, hence my hope for someone here to help me on my way :)

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• OpenGL Mipmapping: how does OpenGL decide on map level?

  - by Droozle

  Hi, I am having trouble implementing mipmapping in OpenGL. I am using OpenFrameworks and have modified the ofTexture class to support the creation and rendering of mipmaps. The following code is the original texture creation code from the class (slightly modified for clarity): glEnable(texData.textureTarget); glBindTexture(texData.textureTarget, (GLuint)texData.textureID); glTexSubImage2D(texData.textureTarget, 0, 0, 0, w, h, texData.glType, texData.pixelType, data); glTexParameteri(texData.textureTarget, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(texData.textureTarget, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glDisable(texData.textureTarget); This is my version with mipmap support: glEnable(texData.textureTarget); glBindTexture(texData.textureTarget, (GLuint)texData.textureID); gluBuild2DMipmaps(texData.textureTarget, texData.glTypeInternal, w, h, texData.glType, texData.pixelType, data); glTexParameteri(texData.textureTarget, GL_TEXTURE_MAG_FILTER, GL_LINEAR_MIPMAP_LINEAR); glTexParameteri(texData.textureTarget, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); glDisable(texData.textureTarget); The code does not generate errors (gluBuild2DMipmaps returns '0') and the textures are rendered without problems. However, I do not see any difference. The scene I render consists of "flat, square tiles" at z=0. It's basically a 2D scene. I zoom in and out by using "glScale()" before drawing the tiles. When I zoom out, the pixels of the tile textures start to "dance", indicating (as far as I can tell) unfiltered texture look-up. See: http://www.youtube.com/watch?v=b_As2Np3m8A at 25s. My question is: since I do not move the camera position, but only use scaling of the whole scene, does this mean OpenGL can not decide on the appropriate mipmap level and uses the full texture size (level 0)? Paul

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• Why might this work on my server but not my schools?

  - by Doug

  I created a captcha just now, and it works PERFECTLY on my own server. On the school's server, it doesn't generate an image. Why might this be? The difference in code is one line. *Edit:*Originally, it was working, but I deleted the directory by mistake and I do not know why did it suddenly work in the first place. Source code on school server: <?php session_save_path("/ichanged/this/path/for/this/post/"); session_start(); $img=imagecreatefromjpeg("bg.jpg"); if( empty($_SESSION['captcha_numbers']) ) { $captcha_numbers = 'error'; } else { $captcha_numbers = $_SESSION['captcha_numbers']; } $image_numbers=$captcha_numbers; $red=rand(100,150); $green=rand(100,255); $blue=rand(100,255); $color=imagecolorallocate($img,255-$red,255-$green,255-$blue); $text=imagettftext($img,12,rand(-7,7),rand(10,20),rand(20,30),$color,"fonts/M04.TTF",$image_numbers); header("Content-type:image/jpeg"); header("Content-Disposition:inline ; filename=secure.jpg"); imagejpeg($img); ?> Source code on my server: <?php session_start(); $img=imagecreatefromjpeg("bg.jpg"); if( empty($_SESSION['captcha_numbers']) ) { $captcha_numbers = 'error'; } else { $captcha_numbers = $_SESSION['captcha_numbers']; } $image_numbers=$captcha_numbers; $red=rand(100,150); $green=rand(100,255); $blue=rand(100,255); $color=imagecolorallocate($img,255-$red,255-$green,255-$blue); $text=imagettftext($img,12,rand(-7,7),rand(10,20),rand(20,30),$color,"fonts/M04.TTF",$image_numbers); header("Content-type:image/jpeg"); header("Content-Disposition:inline ; filename=secure.jpg"); imagejpeg($img); ?>

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