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  • How to write a flexible modular program with good interaction possibilities between modules?

    - by PeterK
    I went through answers on similar topics here on SO but could't find a satisfying answer. Since i know this is a rather large topic, i will try to be more specific. I want to write a program which processes files. The processing is nontrivial, so the best way is to split different phases into standalone modules which then would be used as necessary (since sometimes i will be only interested in the output of module A, sometimes i would need output of five other modules, etc). The thing is, that i need the modules to cooperate, because the output of one might be the input of another. And i need it to be FAST. Moreover i want to avoid doing certain processing more than once (if module A creates some data which then need to be processed by module B and C, i don't want to run module A twice to create the input for modules B,C ). The information the modules need to share would mostly be blocks of binary data and/or offsets into the processed files. The task of the main program would be quite simple - just parse arguments, run required modules (and perhaps give some output, or should this be the task of the modules?). I don't need the modules to be loaded at runtime. It's perfectly fine to have libs with a .h file and recompile the program every time there is a new module or some module is updated. The idea of modules is here mainly because of code readability, maintaining and to be able to have more people working on different modules without the need to have some predefined interface or whatever (on the other hand, some "guidelines" on how to write the modules would be probably required, i know that). We can assume that the file processing is a read-only operation, the original file is not changed. Could someone point me in a good direction on how to do this in C++ ? Any advice is wellcome (links, tutorials, pdf books...).

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  • Possibility of a custom Contacts field with a set list of values and Contacts lookup performance

    - by areyling
    I'm pretty sure it's not viable to do what I'd like to based on some initial research, but I figured it couldn't hurt to ask the community of experts here in case someone knows a way. I'd like to create a custom field for contacts that the user is able to edit from the main Contacts app; however, the user should only be allowed to select from a list of four specific values. A short list of string values would be ideal, but an int with a min/max range would suffice. I'm interested in knowing if it's possible either way, but also wondering if it make sense to go this route performance wise. More specifically, would it be better to look up a contact (based on a phone number) each time a call or SMS message is received or better to store my own set of data (consisting of name, numbers, and the custom field) and just syncing contact info in a thread every so often? Or syncing contacts the first time the app is run and then registering for changes using ContentObserver? Here is a similar question with an answer that explains how to add a custom field to a contact. Thanks in advance.

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  • What if you used the wrong language?

    - by HS
    A reply to another question made me remember a project from some years ago when it turned out that Java was not the right tool to use. I typically only learn a new language when I have a problem that it solves better than the ones I already know. [...] Then I write whatever program I wanted to learn that language for in the first place. [...] By the time I've gotten my target program written, I've usually got a decent handle on the language, not to mention any other features it has, and I've got other ideas to use it for. I did just that back then with Java, because the client thought it to be the right language to use (platform independent) and initial evaluation confirmed that. However, much later in the project there were some issue (can't really remember all the details by now). So, the project that started as a nice learning experience turned into a nightmare toward the end. I was at the brink of switching over to my trusted C++ and doing a complete rewrite. The client was not so much of a problem to convince back then, but my supervisor was strongly opposed because of all the work that already went into the Java version. In hindsight, he was right and the project was complete more or less with the intended features kind of working, but it was the project that I am least proud of by now. Long story short: what do you think, when is it too much and the switch to another technology is worthwhile? I personally would estimate the point of no return to be around 50% of the planned effort, but really want to know, if anyone has real experience with such a switch. And to answer the inevitable question: I do not really care, if the technology switched to is proven or another new thing. The latter would basically need more initial scrutiny based on the past experiences in the problematic project.

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  • What are the differences between mapping,binding and parsing?

    - by sfrj
    I am starting to learn web-services in java EE6. I did web development before, but never nothing related to web services. All is new to me and the books and the tutorials i find in the web are to technical. I started learning about .xsd schemas and also .xml. In that topic i feel confident, i understand what are the schemas used for and what validation means. Now my next step is learning about JAX-B(Java Api for XML Binding). I rode some about it and i did also some practice in my IDE. But i have lots of basic doubts, that make me stuck and cannot feel confident to continue to the next topic. Ill appreciate a lot if someone could explain me well my doubts: What does it mean mapping and what is a mapping tool? What does it mean binding and what is a binding tool? What does it mean parsing and what is a parsing tool? How is JAX-B related to mapping,binding and parsing? I am seeking for a good answer built by you, not just a copy paste from google(Ive already been online a few hours and only got confused).

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  • How do I ensure a Flex dataProvider processes the data synchronously?

    - by Matt Calthrop
    I am using an component, and currently have a dataProvider working that is an ArrayCollection (have a separate question about how to make this an XML file... but I digress). Variable declaration looks like this: [Bindable] private var _dpImageList : ArrayCollection = new ArrayCollection([ {"location" : "path/to/image1.jpg"}, {"location" : "path/to/image2.jpg"}, {"location" : "path/to/image3.jpg"} ]); I then refer to like this: <s:List id="lstImages" width="100%" dataProvider="{_dpImageList}" itemRenderer="path.to.render.ImageRenderer" skinClass="path.to.skins.ListSkin" > <s:layout> <s:HorizontalLayout gap="2" /> </s:layout> </s:List> Currently, it would appear that each item is processed asynchronously. However, I want them to be processed synchronously. Reason: I am displaying a list of images, and I want the leftmost one rendered first, followed by the one to its right, and so on. Edit: I just found this answer. Do you think that could be the same issue?

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  • Pairs from single list

    - by Apalala
    Often enough, I've found the need to process a list by pairs. I was wondering which would be the pythonic and efficient way to do it, and found this on Google: pairs = zip(t[::2], t[1::2]) I thought that was pythonic enough, but after a recent discussion involving idioms versus efficiency, I decided to do some tests: import time from itertools import islice, izip def pairs_1(t): return zip(t[::2], t[1::2]) def pairs_2(t): return izip(t[::2], t[1::2]) def pairs_3(t): return izip(islice(t,None,None,2), islice(t,1,None,2)) A = range(10000) B = xrange(len(A)) def pairs_4(t): # ignore value of t! t = B return izip(islice(t,None,None,2), islice(t,1,None,2)) for f in pairs_1, pairs_2, pairs_3, pairs_4: # time the pairing s = time.time() for i in range(1000): p = f(A) t1 = time.time() - s # time using the pairs s = time.time() for i in range(1000): p = f(A) for a, b in p: pass t2 = time.time() - s print t1, t2, t2-t1 These were the results on my computer: 1.48668909073 2.63187503815 1.14518594742 0.105381965637 1.35109519958 1.24571323395 0.00257992744446 1.46182489395 1.45924496651 0.00251388549805 1.70076990128 1.69825601578 If I'm interpreting them correctly, that should mean that the implementation of lists, list indexing, and list slicing in Python is very efficient. It's a result both comforting and unexpected. Is there another, "better" way of traversing a list in pairs? Note that if the list has an odd number of elements then the last one will not be in any of the pairs. Which would be the right way to ensure that all elements are included? I added these two suggestions from the answers to the tests: def pairwise(t): it = iter(t) return izip(it, it) def chunkwise(t, size=2): it = iter(t) return izip(*[it]*size) These are the results: 0.00159502029419 1.25745987892 1.25586485863 0.00222492218018 1.23795199394 1.23572707176 Results so far Most pythonic and very efficient: pairs = izip(t[::2], t[1::2]) Most efficient and very pythonic: pairs = izip(*[iter(t)]*2) It took me a moment to grok that the first answer uses two iterators while the second uses a single one. To deal with sequences with an odd number of elements, the suggestion has been to augment the original sequence adding one element (None) that gets paired with the previous last element, something that can be achieved with itertools.izip_longest().

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  • Expanding DIV slides behind DIV beneath it...

    - by Paddy
    I'm not sure that I'm going to get an answer here, as I'd need to post a lot of CSS and html to get a working recreation, however... I have structure something like this: <fieldset> <legend>Test A</legend> <h3>Test A</h3> <p> Something here. </p> <div style="display:hidden;">I'm dynamically displayed</div> </fieldset> <fieldset> <legend>Test B</legend> <h3>Test B</h3> <p> Something B here. </p> </fieldset> I have code that toggles the display of my hidden div using jQuery and .show(). This works fine in IE8, firefox and Safari, but when I stick IE8 into compatibility mode, then the first fieldset (Test A) will expand, but the expansion happens behind the second fieldset, which doesn't move (i.e. it slides down behind it). I have quite a bit of CSS in use here, and I'm going to have to go back and unpick the whold lot, which isn't a fun idea. If anybody has any idea of one of the IE7 rendering issues that might be affecting this, then I'd very much appreciate it. (note that there is more to the content in these fieldsets than shown, including floated divs). Quick note - if I stick IE7 into quirks mode, it works (but wrecks the rest of my layout) - in standards mode, I get the above behaviour.

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  • Why does Android allocate more memory than needed when loading images

    - by Simon
    Folks, I don't think that this is a duplicate and is NOT one of those how do I avoid OOMs questions. This is a genuine quest for knowledge so hold off on those down votes please... Imagine I have a JPEG of 500x500 pixels. I load it as ARGB_8888 which is as "bad as it gets". I would expect Android to allocate 500x500x4 bytes = a little under 1MB however, look at a heap dump and you will see that Android allocates significantly more, often factors of 5-10 times greater. You frequently see questions on here about OOMS where the stack trace shows a heap request of say 15MB and it is ALWAYS much larger than is required simply to hold the bytes of the image. The OP usually catches some downvotes then is bombarded with stock answers and comments about using less memory (thanks Romain!) and in scaling. I think there is more than meets the eye here. Anybody know why this is? If there is no apparent answer, I will put together an SSCCE if it helps. PS. I assume that JPEG vs PNG etc is irrelevant since we're talking about the memory usage of the backing bitmap which is simply x times y times BPP - or am I being slow?

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  • MYSQL JOIN WHERE ISSUES - need some kind of if condition

    - by Breezer
    Hi Well this will be hard to explain but ill do my best The thing is i have 4 tables all with a specific column to relate to eachother. 1 table with users(agent_users) , 1 with working hours(agent_pers), 1 with sold items(agent_stat),1 with project(agent_pro) the user and the project table is irrelevant in the issue at hand but to give you a better understanding why certain tables is included in my query i decided to still mention them =) The thing is that I use 2 pages to insert data to the working hour and the sold items during that time tables, then i have a third page to summarize everything for current month, the query for that is as following: SELECT *, SUM(sv_p_kom),SUM(sv_p_gick),SUM(sv_p_lunch) FROM (( agent_users LEFT JOIN agent_pers ON agent_users.sv_aid = agent_pers.sv_p_uid) LEFT JOIN agent_stat ON agent_pers.sv_p_uid = agent_stat.sv_s_uid) LEFT JOIN agent_pro ON agent_pers.sv_p_pid=agent_pro.p_id WHERE MONTH(agent_pers.sv_p_datum) =7 GROUP BY sv_aname so the problem is now that i dont want sold items from previous months to get included in the data received, i know i could solve that by simple adding in the WHERE part MONTH(agent_stat.sv_s_datum) =7 but then if no items been sold that month no data at all will show up not the time or anything. Any aid on how i could solve this is greatly appreciated. if there's something that's not so clear dont hesitate to ask and ill try my best to answer. after all my english isn't the best out there :P regards breezer

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  • Difference in BackgroundWorker thread access in VS2010 / .NET 4.0?

    - by Jonners
    Here's an interesting one - in VS2005 / VS2008 running against .NET 2.0 / .NET 3.0 / .NET 3.5, a BackgroundWorker thread may not directly update controls on a WinForms form that initiated that thread - you'll get a System.InvalidOperationException out of the BackgroundWorker stating "Cross-thread operation not valid: Control 'thecontrol' accessed from a thread other than the thread it was created on". I remember hitting this back in 2004 or so when I first started writing .NET WinForms apps with background threads. There are several ways around the problem - this is not a question asking for that answer. I've been told recently that this kind of operation is now allowed when written in VS2010 / .NET 4.0. This seems unlikely to me, since this kind of object access restriction has always been a fairly fundamental part of thread-safe programming. Allowing a BackgroundWorker thread direct access to objects owned not by itself but by its parent UI form seems contrary to that principle. A trawl through the .NET 4.0 docs hasn't revealed any obvious changes that could account for this behaviour. I don't have VS2010 / .NET 4.0 to test this out - does anyone who has access to that toolset know for sure whether the model has changed to allow that kind of thread interaction? I'd like to either take advantage of it in future, or deploy the cluestick. ;)

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  • SWIG interface to receive an opaque struct reference in Java through function argument

    - by Beeo
    I am trying to use SWIG in order to use the Spotify API (libspotify) for Android: https://developer.spotify.com/technologies/libspotify/ I am having trouble defining the SWIG interface file to be able to successfully call the following native C function: sp_error sp_session_create(const sp_session_config * config, sp_session ** sess); Which in C would be called like this: //config struct defined previously sp_session *sess; sp_session_create(&config, &sess); But in Java I would need to call it like this: //config object defined previously sp_session javaSess = new sp_session(); sp_session_create(config, javaSess); sp_session is an opaque struct and is only defined in libspotify's API.h file as: typedef struct sp_session sp_session; I'm expecting the libspotify library to create it and give me a reference to it. The only thing I need that reference for then is to pass to other functions in the API. I believe the answer lies within the SWIG interface and typemaps, but I have been unsuccessful in trying to apply the examples I found in the documentation: http://www.swig.org/Doc2.0/SWIGDocumentation.html#Java_struct_pointer_pointer `http://www.swig.org/Doc2.0/SWIGDocumentation.html#Java_using_typemaps_return_arguments Help!

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  • C# Virtual method call in constructor - how to refactor?

    - by Cristi Diaconescu
    I have an abstract class for database-agnostic cursor actions. Derived from that, there are classes that implement the abstract methods for handling database-specific stuff. The problem is, the base class ctor needs to call an abstract method - when the ctor is called, it needs to initialize the database-specific cursor. I know why this shouldn't be done, I don't need that explanation! This is my first implementation, that obviously doesn't work - it's the textbook "wrong way" of doing it. The overridden method accesses a field from the derived class, which is not yet instantiated: public abstract class CursorReader { private readonly int m_rowCount; protected CursorReader() { m_rowCount = CreateCursor(sqlCmd); //virtual call ! } protected abstract int CreateCursor(string sqlCmd); } public class SqlCursorReader : CursorReader { private SqlConnection m_sqlConnection; public SqlCursorReader(string sqlCmd, SqlConnection sqlConnection) { m_sqlConnection = sqlConnection; //field initialized here } protected override int CreateCursor(string sqlCmd) { //uses not-yet-initialized member *m_sqlConnection* //so this throws a NullReferenceException var cursor = new CustomCursor(sqlCmd, m_sqlConnection); return cursor.Count(); } } I will follow up with an answer on my attempts to fix this...

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  • How to implement generic callbacks in C++

    - by Kylotan
    Forgive my ignorance in asking this basic question but I've become so used to using Python where this sort of thing is trivial that I've completely forgotten how I would attempt this in C++. I want to be able to pass a callback to a function that performs a slow process in the background, and have it called later when the process is complete. This callback could be a free function, a static function, or a member function. I'd also like to be able to inject some arbitrary arguments in there for context. (ie. Implementing a very poor man's coroutine, in a way.) On top of that, this function will always take a std::string, which is the output of the process. I don't mind if the position of this argument in the final callback parameter list is fixed. I get the feeling that the answer will involve boost::bind and boost::function but I can't work out the precise invocations that would be necessary in order to create arbitrary callables (while currying them to just take a single string), store them in the background process, and invoke the callable correctly with the string parameter.

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  • IF-block brackets: best practice

    - by MasterPeter
    I am preparing a short tutorial for level 1 uni students learning JavaScript basics. The task is to validate a phone number. The number must not contain non-digits and must be 14 digits long or less. The following code excerpt is what I came up with and I would like to make it as readable as possible. if ( //set of rules for invalid phone number phoneNumber.length == 0 //empty || phoneNumber.length > 14 //too long || /\D/.test(phoneNumber) //contains non-digits ) { setMessageText(invalid); } else { setMessageText(valid); } A simple question I can not quite answer myself and would like to hear your opinions on: How to position the surrounding (outermost) brackets? It's hard to see the difference between a normal and a curly bracket. Do you usually put the last ) on the same line as the last condition? Do you keep the first opening ( on a line by itself? Do you wrap each individual sub-condition in brackets too? Do you align horizontally the first ( with the last ), or do you place the last ) in the same column as the if? Do you keep ) { on a separate line or you place the last ) on the same line with the last sub-condition and then place the opening { on a new line? Or do you just put the ) { on the same line as the last sub-condition? Community wiki.

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  • How to implement a 'safe' periodical executer without using the Rails helpers?

    - by Robbie
    I am very new to Ruby on Rails and was never really big on writing JavaScript, so the built in helpers were like a tiny silce of heaven. However I have recently learned that using the helper methods creates "obtrusive javascript" so I am doing a tiny bit of refactoring to get all this messy code out of my view. I'm also using the Prototype API to figure out what all these functions do. Right now, I have: <%= periodically_call_remote(:url => {:action => "tablerefresh", :id => 1 }, :frequency => '5', :complete => "load('26', 'table1', request.responseText)")%> Which produces: <script type="text/javascript"> //<![CDATA[ new PeriodicalExecuter(function() {new Ajax.Request('/qrpsdrail/grids/tablerefresh/1', {asynchronous:true, evalScripts:true, onComplete:function(request){load('26', 'table1', request.responseText)}, parameters:'authenticity_token=' + encodeURIComponent('dfG7wWyVYEpelfdZvBWk7MlhzZoK7VvtT/HDi3w7gPM=')})}, 5) //]]> </script> My concern is that the "encodeURIComponent" and the presence of "authenticity_token" are generated by Rails. I'm assuming these are used to assure the validity of a request. (Ensuring a request comes from a currently active session?) If that is the case, how can I implement this in application.js 'safely'? It seems that the built in method, although obtrusive, does add some beneficial security. Thanks, in advance, to all who answer.

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  • Project Euler, Problem 10 java solution not working

    - by Dennis S
    Hi, I'm trying to find the sum of the prime numbers < 2'000'000. This is my solution in java but I can't seem get the correct answer. Please give some input on what could be wrong and general advice on the code is appreciated. Printing 'sum' gives: 1308111344, which is incorrect. /* The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. */ class Helper{ public void run(){ Integer sum = 0; for(int i = 2; i < 2000000; i++){ if(isPrime(i)) sum += i; } System.out.println(sum); } private boolean isPrime(int nr){ if(nr == 2) return true; else if(nr == 1) return false; if(nr % 2 == 0) return false; for(int i = 3; i < Math.sqrt(nr); i += 2){ if(nr % i == 0) return false; } return true; } } class Problem{ public static void main(String[] args){ Helper p = new Helper(); p.run(); } }

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  • scanf a byte then print it out?

    - by Sarah
    I've searched around to see if I can find this answer but I can't seem to (please let me know if I'm wrong). I am trying to use scanf to read in a byte, an unsigned int and a char in one .c file and I am trying to access this byte in a different .c file and print it out. (I have already checked to make sure I have included all the appropriate parameters everywhere) But I keep getting errors. The warnings are: database.c: In function ‘addCitizen’: database.c:23:2: warning: format ‘%hhu’ expects argument of type ‘int’, but argument 2 has type ‘byte *’ [-Wformat] database.c:24:2: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 2 has type ‘int *’ [-Wformat] database.c:25:2: warning: format ‘%c’ expects argument of type ‘int’, but argument 2 has type ‘char *’ [-Wformat] where I'm scanf'ing: // Request loop while (count-- != 0) { while (1){ // Get values from the user int error = scanf ("%79s %hhu %u %c", tname, &tdist, &tyear, &tgender); addCitizen(db, tname, &tdist, &tyear, &tgender); where I'm printing: void addCitizen(Database *db, char *tname, byte *tdist, int *tyear, char *tgender){ //needs to find the right place in memory to put this stuff and then put it there printf("\nName is: %79s\n", tname); printf("District is: %hhu\n", tdist); printf("Year of birth is: %u\n", tyear); printf("Gender is:%c\n", tgender); I'm not sure where I'm going wrong?

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  • .NET Regex - Replace multiple characters at once without overwriting?

    - by Everaldo Aguiar
    I'm implementing a c# program that should automatize a Mono-alphabetic substitution cipher. The functionality i'm working on at the moment is the simplest one: The user will provide a plain text and a cipher alphabet, for example: Plain text(input): THIS IS A TEST Cipher alphabet: A - Y, H - Z, I - K, S - L, E - J, T - Q Cipher Text(output): QZKL KL QJLQ I thought of using regular expressions since I've been programming in perl for a while, but I'm encountering some problems on c#. First I would like to know if someone would have a suggestion for a regular expression that would replace all occurrence of each letter by its corresponding cipher letter (provided by user) at once and without overwriting anything. Example: In this case, user provides plaintext "TEST", and on his cipher alphabet, he wishes to have all his T's replaced with E's, E's replaced with Y and S replaced with J. My first thought was to substitute each occurrence of a letter with an individual character and then replace that character by the cipherletter corresponding to the plaintext letter provided. Using the same example word "TEST", the steps taken by the program to provide an answer would be: 1 - replace T's with (lets say) @ 2 - replace E's with # 3 - replace S's with & 4 - Replace @ with E, # with Y, & with j 5 - Output = EYJE This solution doesn't seem to work for large texts. I would like to know if anyone can think of a single regular expression that would allow me to replace each letter in a given text by its corresponding letter in a 26-letter cipher alphabet without the need of splitting the task in an intermediate step as I mentioned. If it helps visualize the process, this is a print screen of my GUI for the program:

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  • Assign Multiple Custom User Roles to a Custom Post Type

    - by OUHSD Webmaster
    Okay here's the situation.... I'm working on a my business website. There will be a work/portfolio area. "Work" is a custom post type. "Designer" is a custom user role. "Client" is a custom user role. In creating a new "Work" post I would like to be able to select both a "designer" and "Client" to assign to the piece of work, as I would assign an author to a regular ol' post. I tried the method from this answer but it did not work for me. ) I placed it in my functions.php file. ` add_filter('wp_dropdown_users', 'test'); function test($output) { global $post; //Doing it only for the custom post type if($post->post_type == 'work') { $users = get_users(array('role'=>'designer')); //We're forming a new select with our values, you can add an option //with value 1, and text as 'admin' if you want the admin to be listed as well, //optionally you can use a simple string replace trick to insert your options, //if you don't want to override the defaults $output .= "<select id='post_author_override' name='post_author_override' class=''>"; foreach($users as $user) { $output .= "<option value='".$user->id."'>".$user->user_login."</option>"; } $output .= "</select>"; } return $output; } ` Any help would be extremely appreciated!

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  • What is happening in this T-SQL code? (Concatenting the results of a SELECT statement)

    - by Ben McCormack
    I'm just starting to learn T-SQL and could use some help in understanding what's going on in a particular block of code. I modified some code in an answer I received in a previous question, and here is the code in question: DECLARE @column_list AS varchar(max) SELECT @column_list = COALESCE(@column_list, ',') + 'SUM(Case When Sku2=' + CONVERT(varchar, Sku2) + ' Then Quantity Else 0 End) As [' + CONVERT(varchar, Sku2) + ' - ' + Convert(varchar,Description) +'],' FROM OrderDetailDeliveryReview Inner Join InvMast on SKU2 = SKU and LocationTypeID=4 GROUP BY Sku2 , Description ORDER BY Sku2 Set @column_list = Left(@column_list,Len(@column_list)-1) Select @column_list ---------------------------------------- 1 row is returned: ,SUM(Case When Sku2=157 Then Quantity Else 0 End) As [157 -..., SUM(Case ... The T-SQL code does exactly what I want, which is to make a single result based on the results of a query, which will then be used in another query. However, I can't figure out how the SELECT @column_list =... statement is putting multiple values into a single string of characters by being inside a SELECT statement. Without the assignment to @column_list, the SELECT statement would simply return multiple rows. How is it that by having the variable within the SELECT statement that the results get "flattened" down into one value? How should I read this T-SQL to properly understand what's going on?

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  • Writing a VM - well formed bytecode?

    - by David Titarenco
    Hi, I'm writing a virtual machine in C just for fun. Lame, I know, but luckily I'm on SO so hopefully no one will make fun :) I wrote a really quick'n'dirty VM that reads lines of (my own) ASM and does stuff. Right now, I only have 3 instructions: add, jmp, end. All is well and it's actually pretty cool being able to feed lines (doing it something like write_line(&prog[1], "jmp", regA, regB, 0); and then running the program: while (machine.code_pointer <= BOUNDS && DONE != true) { run_line(&prog[machine.cp]); } I'm using an opcode lookup table (which may not be efficient but it's elegant) in C and everything seems to be working OK. My question is more of a "best practices" question but I do think there's a correct answer to it. I'm making the VM able to read binary files (storing bytes in unsigned char[]) and execute bytecode. My question is: is it the VM's job to make sure the bytecode is well formed or is it just the compiler's job to make sure the binary file it spits out is well formed? I only ask this because what would happen if someone would edit a binary file and screw stuff up (delete arbitrary parts of it, etc). Clearly, the program would be buggy and probably not functional. Is this even the VM's problem? I'm sure that people much smarter than me have figured out solutions to these problems, I'm just curious what they are!

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  • GlassFish 3: how do you change the (default) logging format?

    - by Kawu
    The question originated from here: http://www.java.net/forum/topic/glassfish/glassfish/configuring-glassfish-logging-format - without an answer. The default GlassFish 3 logging format of is very annoying, much too long. [#|2012-03-02T09:22:03.165+0100|SEVERE|glassfish3.1.2|javax.enterprise.system.std.com.sun.enterprise.server.logging|_ThreadID=113;_ThreadName=AWT-EventQueue-0;| MESSAGE... ] This is just a horrible default IMO. The docs just explain all the fields, but not how to change the format: http://docs.oracle.com/cd/E18930_01/html/821-2416/abluk.html Note, that I deploy SLF4J along with my webapp which should pick up the format as well. How do you change the logging format? FYI: The links here are outdated: Install log formater in glassfish... The question here hasn't been answered: How to configure GlassFish logging to show milliseconds in timestamps?... The posting here resulted in nothing: http://www.java.net/forum/topic/glassfish/glassfish/cant-seem-configure-... It looks like GlassFish logging configuration is an issue of its own. Can anybody help?

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  • How do I know which Object I clicked?

    - by Nick
    Here's the deal: I'm working on a personal portfolio in AS3 and I've run into a problem which I can't seem to find a logical answer to. I want everything (well, most of it) to be editable with an XML file, including my menu. My menu is just a Sprite with some text on it and a Tweener-tween, no big deal. But, I forgot to think of a way how I can determine which menu-item I have clicked. This is in my Main.as private function xmlLoaded(e:Event):void { xml = e.target.xml; menu = new Menu(xml); menu.x = 0; menu.y = stage.stageHeight / 2 - menu.height / 2; addChild(menu); } In Menu.as public function Menu(xml:XML) { for each (var eachMenuItem:XML in xml.menu.item) { menuItem = new MenuItem(eachMenuItem); menuItem.y += yPos; addChild(menuItem); yPos += menuItem.height + 3; } } and in my MenuItem.as, everything works - I have a fancy tween when I hover over it, but when I click a menu-item, I want something to appear ofcourse. How do I know which one I clicked? I've tried with pushing everything in an array, but that didn't work out well (or maybe I'm doing it wrong). Also tried a global counter, but that's not working either because the value will always be amount of items in my XML file. Also tried e.currentTarget in my click-function, but when I trace that, all of them are "Object Sprite".. I need something so I can give each a unique "name"? Thanks in advance!

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  • Type errors when using same name

    - by lykimq
    I have 3 files: 1) cpf0.ml type string = char list type url = string type var = string type name = string type symbol = | Symbol_name of name 2) problem.ml: type symbol = | Ident of string 3) test.ml open Problem;; open Cpf0;; let symbol b = function | Symbol_name n -> Ident n When I combine test.ml: ocamlc -c test.ml. I received an error: This expression has type Cpf0.name = char list but an expression was expected of type string Could you please help me to correct it? Thank you very much EDIT: Thank you for your answer. I want to explain more about these 3 files: Because I am working with extraction in Coq to Ocaml type: cpf0.ml is generated from cpf.v : Require Import String. Definition string := string. Definition name := string. Inductive symbol := | Symbol_name : name -> symbol. The code extraction.v: Set Extraction Optimize. Extraction Language Ocaml. Require ExtrOcamlBasic ExtrOcamlString. Extraction Blacklist cpf list. where ExtrOcamlString I opened: open Cpf0;; in problem.ml, and I got a new problem because in problem.ml they have another definition for type string This expression has type Cpf0.string = char list but an expression was expected of type Util.StrSet.elt = string Here is a definition in util.ml defined type string: module Str = struct type t = string end;; module StrOrd = Ord.Make (Str);; module StrSet = Set.Make (StrOrd);; module StrMap = Map.Make (StrOrd);; let set_add_chk x s = if StrSet.mem x s then failwith (x ^ " already declared") else StrSet.add x s;; I was trying to change t = string to t = char list, but if I do that I have to change a lot of function it depend on (for example: set_add_chk above). Could you please give me a good idea? how I would do in this case.

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  • Moving front page (cursebird or foursquare)

    - by Dan Samuels
    Ok so I'll be honest, I have a good amount of experience with php/mysql, I've just started learning jQuery and I've done very little, but some with ajax. So using the terms ajax/jquery interchangeably are a bit confusing to me. Anyway as the title suggest I have a website with 5 items, and I want them to move (meaning, if a more recent one is entered, remove the last item, and put the new one on top), they are 5 of the most recent items in the database table, now I've coded jquery as a test so it fades out the last one, the whole thing moves down, makes room at the top, and fades in a new one. However, it's a test and has 0 interaction with the database, the one that fades in is just in a hidden div. So the jQuery part is taken care of. So I'm unsure how to go about this, I was thinking maybe have ajax check a website off the page that has those 5 items in raw format, and if they change then to refresh? Not looking for a "plz code 4 me" answer, just the concept of how it would work, or some links to get off to the right start. edit - Also, the 5 items are ranked, so if I click item 3 I need it to move above item 2 refreshlessly, so this causes a whole other issue I assume.

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