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  • Violation of the DRY Principle

    - by Onorio Catenacci
    I am sure there's a name for this anti-pattern somewhere; however I am not familiar enough with the anti-pattern literature to know it. Consider the following scenario: or0 is a member function in a class. For better or worse, it's heavily dependent on class member variables. Programmer A comes along and needs functionality like or0 but rather than calling or0, Programmer A copies and renames the entire class. I'm guessing that she doesn't call or0 because, as I say, it's heavily dependent on member variables for its functionality. Or maybe she's a junior programmer and doesn't know how to call it from other code. So now we've got or0 and c0 (c for copy). I can't completely fault Programmer A for this approach--we all get under tight deadlines and we hack code to get work done. Several programmers maintain or0 so it's now version orN. c0 is now version cN. Unfortunately most of the programmers that maintained the class containing or0 seemed to be completely unaware of c0--which is one of the strongest arguments I can think of for the wisdom of the DRY principle. And there may also have been independent maintainance of the code in c. Either way it appears that or0 and c0 were maintained independent of each other. And, joy and happiness, an error is occurring in cN that does not occur in orN. So I have a few questions: 1.) Is there a name for this anti-pattern? I've seen this happen so often I'd find it hard to believe this is not a named anti-pattern. 2.) I can see a few alternatives: a.) Fix orN to take a parameter that specifies the values of all the member variables it needs. Then modify cN to call orN with all of the needed parameters passed in. b.) Try to manually port fixes from orN to cN. (Mind you I don't want to do this but it is a realistic possibility.) c.) Recopy orN to cN--again, yuck but I list it for sake of completeness. d.) Try to figure out where cN is broken and then repair it independently of orN. Alternative a seems like the best fix in the long term but I doubt the customer will let me implement it. Never time or money to fix things right but always time and money to repair the same problem 40 or 50 times, right? Can anyone suggest other approaches I may not have considered? If you were in my place, which approach would you take? If there are other questions and answers here along these lines, please post links to them. I don't mind removing this question if it's a dupe but my searching hasn't turned up anything that addresses this question yet. EDIT: Thanks everyone for all the thoughtful responses. I asked about a name for the anti-pattern so I could research it further on my own. I'm surprised this particular bad coding practice doesn't seem to have a "canonical" name for it.

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  • Thread-safe data structures

    - by Inso Reiges
    Hello, I have to design a data structure that is to be used in a multi-threaded environment. The basic API is simple: insert element, remove element, retrieve element, check that element exists. The structure's implementation uses implicit locking to guarantee the atomicity of a single API call. After i implemented this it became apparent, that what i really need is atomicity across several API calls. For example if a caller needs to check the existence of an element before trying to insert it he can't do that atomically even if each single API call is atomic: if(!data_structure.exists(element)) { data_structure.insert(element); } The example is somewhat awkward, but the basic point is that we can't trust the result of exists call anymore after we return from atomic context (the generated assembly clearly shows a minor chance of context switch between the two calls). What i currently have in mind to solve this is exposing the lock through the data structure's public API. This way clients will have to explicitly lock things, but at least they won't have to create their own locks. Is there a better commonly-known solution to these kinds of problems? And as long as we're at it, can you advise some good literature on thread-safe design? Thank you.

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  • Embeddable forum software

    - by Rented
    I am in the planning stages of a specific subject matter community web site, and one feature I feel is required is that of member discussions. However, not in a typical forum style. For example, I don't want the members to have to navigate away from their own "user space" in order to discuss a topic. I think it is best described with an analogous example. Lets say the site is for literature buffs, and each member has a set of pages for keeping notes, progress, questions, etc. on books they are studying/reading. So Joe will have one page for Great Expectations, another for Hamlet, a third for I, Robot, and so forth. Likewise, Jane will have a page for Don Quixote, Lord of the Flies, and also I, Robot. Now, wouldn't it be nice if Joe and Jane could discuss I, Robot from within their own respective pages? Now, at first thought, roll your own seems like the way to go. However, once we start getting into issues such as spam blocking, banning, ratings, pruning, archiving, flooding and so on, well "roll your own" doesn't sound too appealing anymore. Also, I have next to zero experience with forum software. So I'm looking for forum software that has an extensive API or is generally very integration-friendly. I would like to be able to create user groups, topics, permissions, etc. programmatically,as well as the obvious user authentication (most seem open in that respect). The site will most probably be built with Java. Tangler seems like a descent option, but it seems less mature than what I'd prefer.

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  • Resources related to data-mining and gaming on social networks

    - by darren
    Hi all I'm interested in the problem of patterning mining among players of social networking games. For example detecting cheaters of a game, given a company's user database. So far I have been following the usual recipe for a data mining project: construct a data warehouse that aggregates significant information select a classifier, and train it with a subsectio of records from the warehouse validate classifier with another test set lather, rinse, repeat Surprisingly, I've found very little in this area regarding literature, best practices, etc. I am hoping to crowdsource the information gathering problem here. Specifically what I'm looking for: What classifiers have worked will for this type of pattern mining (it seems highly temporal, users playing games, users receiving rewards, users transferring prizes etc). Are there any highly agreed upon attributes specific to social networking / gaming data? What is a practical amount of information that should be considered? One problem I've run into is data overload, where queries and data cleansing may take days to complete. Related to point above, what hardware resources are required to produce results? I've found it difficult to estimate the amount of computing power I will require for production use. It has become apparent that a white box in the corner does not have enough horse-power for such a project. Are companies generally resorting to cloud solutions? Are they buying clusters? Basically, any resources (theoretical, academic, or practical) about implementing a social networking / gaming pattern-mining program would be very much appreciated. Thanks.

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  • Efficient Context-Free Grammar parser, preferably Python-friendly

    - by Max Shawabkeh
    I am in need of parsing a small subset of English for one of my project, described as a context-free grammar with (1-level) feature structures (example) and I need to do it efficiently . Right now I'm using NLTK's parser which produces the right output but is very slow. For my grammar of ~450 fairly ambiguous non-lexicon rules and half a million lexical entries, parsing simple sentences can take anywhere from 2 to 30 seconds, depending it seems on the number of resulting trees. Lexical entries have little to no effect on performance. Another problem is that loading the (25MB) grammar+lexicon at the beginning can take up to a minute. From what I can find in literature, the running time of the algorithm used to parse such a grammar (Earley or CKY) should be linear to the size of the grammar and cubic to the size of the input token list. My experience with NLTK indicates that ambiguity is what hurts the performance most, not the absolute size of the grammar. So now I'm looking for a CFG parser to replace NLTK. I've been considering PLY but I can't tell whether it supports feature structures in CFGs, which are required in my case, and the examples I've seen seem to be doing a lot of procedural parsing rather than just specifying a grammar. Can anybody show me an example of PLY both supporting feature structs and using a declarative grammar? I'm also fine with any other parser that can do what I need efficiently. A Python interface is preferable but not absolutely necessary.

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  • Unit testing JSON output module, best practices

    - by Banang
    I am currently working on a module that takes one of our business objects and returns a json representation of that object to the caller. Due to limitations in our environment I am unable to use any existing json writer, so I have written my own, which is then used by the business object writer to serialize my objects. The json writer is tested in a way similar to this @Test public void writeEmptyArrayTest() { String expected = "[ ]"; writer.array().endArray(); assertEquals(expected, writer.toString()); } which is only manageable because of the small output each instruction produces, even though I keep feeling there must be a better way. The problem I am now facing is writing tests for the object writer module, where the output is much larger and much less manageable. The risk of spelling mistakes in the expected strings mucking up my tests seem too great, and writing code in this fashion seems both silly and unmanageable in a long term perspective. I keep feeling like I want to write tests to ensure that my tests are behaving correctly, and this feeling worries me. Therefore, is there a better way of doing this? Surely there must be? Does anyone know of any good literature in regard to this specific case (doesn't have to be json, but you know what I mean)? Grateful for all help.

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  • Implementing crossover in genetic programming

    - by Name
    Hi, I'm writing a genetic programming (GP) system (in C but that's a minor detail). I've read a lot of the literature (Koza, Poli, Langdon, Banzhaf, Brameier, et al) but there are some implementation details I've never seen explained. For example: I'm using a steady state population rather than a generational approach, primarily to use all of the computer's memory rather than reserve half for the interim population. Q1. In GP, as opposed to GA, when you perform crossover you select two parents but do you create one child or two, or is that a free choice you have? Q2. In steady state GP, as opposed to a generational system, what members of the population do the children created by crossover replace? This is what I haven't seen discussed. Is it the two parents, or is it two other, randomly-selected members? I can understand if it's the latter, and that you might use negative tournament selection to choose members to replace, but would that not create premature convergence? (After a crossover event the population contains the two original parents plus two children of those parents, and two other random members get removed. Elitism is inherent.) Q3. Is there a Web forum or mailing list focused on GP? Oddly I haven't found one. Yahoo's GP group is used almost exclusively for announcements, the Poli/Langdon Field Guide forum is almost silent, and GP discussions on general/game programming sites like gamedev.net are very basic. Thanks for any help you can provide!

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  • Thread implemented as a Singleton

    - by rocknroll
    Hi all, I have a commercial application made with C,C++/Qt on Linux platform. The app collects data from different sensors and displays them on GUI. Each of the protocol for interfacing with sensors is implemented using singleton pattern and threads from Qt QThreads class. All the protocols except one work fine. Each protocol's run function for thread has following structure: void <ProtocolClassName>::run() { while(!mStop) //check whether screen is closed or not { mutex.lock() while(!waitcondition.wait(&mutex,5)) { if(mStop) return; } //Code for receiving and processing incoming data mutex.unlock(); } //end while } Hierarchy of GUI. 1.Login screen. 2. Screen of action. When a user logs in from login screen, we enter the action screen where all data is displayed and all the thread's for different sensors start. They wait on mStop variable in idle time and when data arrives they jump to receiving and processing data. Incoming data for the problem protocol is 117 bytes. In the main GUI threads there are timers which when timeout, grab the running instance of protocol using <ProtocolName>::instance() function Check the update variable of singleton class if its true and display the data. When the data display is done they reset the update variable in singleton class to false. The problematic protocol has the update time of 1 sec, which is also the frame rate of protocol. When I comment out the display function it runs fine. But when display is activated the application hangs consistently after 6-7 hours. I have asked this question on many forums but haven't received any worthwhile suggestions. I Hope that here I will get some help. Also, I have read a lot of literature on Singleton, multithreading, and found that people always discourage the use of singletons especially in C++. But in my application I can think of no other design for implementation. Thanks in advance A Hapless programmer

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  • How can I test this SQL Server performance Utility?

    - by Martin Smith
    As part of my MSc I need to do a three month project later this year. I have decided to do something which will likely be useful for me in the workplace and spend the time getting to understand SQL Server internals. The deliverable for this project will be a performance advisor looking at a variety of different rules. Some static such as finding redundant indexes, some more dynamic such as using XEvents to find outlying invocations of stored procedure execution times when certain parameters are passed. I am struggling to come up with a good way of testing this though. I can obviously design a "bad" database and a synthetic workload that my tool will pick up issues on but I also need to demonstrate that it has real world utility. Looking at the self tuning database literature it is common to use TPC benchmarks but I've had a look at the TPCC site and it looks very time consuming to implement and not that good a fit to my project's testing needs in any event (I would still be able to "rig" it by the decisions I made on indexing or physical architecture). Plan A would be to find willing beta tester(s) but in the event that isn't possible I will need a fallback plan. The best idea I have come up with so far is to use the various MS sample applications as examples of real world applications. e.g. http://msftdpprodsamples.codeplex.com/ http://www.asp.net/community/projects/ Does anyone have any better suggestions?

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  • Solving problems involving more complex data structures with CUDA

    - by Nils
    So I read a bit about CUDA and GPU programming. I noticed a few things such that access to global memory is slow (therefore shared memory should be used) and that the execution path of threads in a warp should not diverge. I also looked at the (dense) matrix multiplication example, described in the programmers manual and the nbody problem. And the trick with the implementation seems to be the same: Arrange the calculation in a grid (which it already is in case of the matrix mul); then subdivide the grid into smaller tiles; fetch the tiles into shared memory and let the threads calculate as long as possible, until it needs to reload data from the global memory into shared memory. In case of the nbody problem the calculation for each body-body interaction is exactly the same (page 682): bodyBodyInteraction(float4 bi, float4 bj, float3 ai) It takes two bodies and an acceleration vectors. The body vector has four components it's position and the weight. When reading the paper, the calculation is understood easily. But what is if we have a more complex object, with a dynamic data structure? For now just assume that we have an object (similar to the body object presented in the paper) which has a list of other objects attached and the number of objects attached is different in each thread. How could I implement that without having the execution paths of the threads to diverge? I'm also looking for literature which explains how different algorithms involving more complex data structures can be effectively implemented in CUDA.

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  • Regressing panel data in SAS.

    - by John
    Hey Guys, thanks to your help I succesfully managed all my databases! I am now looking at a panel data set on which I have to regress. Since I only started my Phd this semester together with the econometrics courses I am still new to many statistic applications and regression methods. I want to do a simple regression as in Y = x1 x2 x3 etc, now I already browsed through some literature and found that for panel data it's common to do a fixed effects regression. Also, my Y variable only has positive values so I was thinking in the direction of a Tobit model? I'm doing some research concerning the coverage of analysts in the financial business. My independent variable is the coverage of analysts on a certain firm, so per observation i have 1 analyst and 1 firm, together with different characteristics(market cap and betas etc) of the firm. All this data is monthly. As coverage cannot become negative (only 0) I was thinking of a Tobit model? Do you guys have any ideas what would be a good regression method? Or have some good sources (e books, written books, through university I have access to almost anything concerning my field of work) of information (cause I do have to learn these things for future research)? Thanks!

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  • categorize a set of phrases into a set of similar phrases

    - by Dingo
    I have a few apps that generate textual tracing information (logs) to log files. The tracing information is the typical printf() style - i.e. there are a lot of log entries that are similar (same format argument to printf), but differ where the format string had parameters. What would be an algorithm (url, books, articles, ...) that will allow me to analyze the log entries and categorize them into several bins/containers, where each bin has one associated format? Essentially, what I would like is to transform the raw log entries into (formatA, arg0 ... argN) instances, where formatA is shared among many log entries. The formatA does not have to be the exact format used to generate the entry (even more so if this makes the algo simpler). Most of the literature and web-info I found deals with exact matching, a max substring matching, or a k-difference (with k known/fixed ahead of time). Also, it focuses on matching a pair of (long) strings, or a single bin output (one match among all input). My case is somewhat different, since I have to discover what represents a (good-enough) match (generally a sequence of discontinuous strings), and then categorize each input entries to one of the discovered matches. Lastly, I'm not looking for a perfect algorithm, but something simple/easy to maintain. Thanks!

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  • What does flushing thread local memory to global memory mean?

    - by Jack Griffith
    Hi, I am aware that the purpose of volatile variables in Java is that writes to such variables are immediately visible to other threads. I am also aware that one of the effects of a synchronized block is to flush thread-local memory to global memory. I have never fully understood the references to 'thread-local' memory in this context. I understand that data which only exists on the stack is thread-local, but when talking about objects on the heap my understanding becomes hazy. I was hoping that to get comments on the following points: When executing on a machine with multiple processors, does flushing thread-local memory simply refer to the flushing of the CPU cache into RAM? When executing on a uniprocessor machine, does this mean anything at all? If it is possible for the heap to have the same variable at two different memory locations (each accessed by a different thread), under what circumstances would this arise? What implications does this have to garbage collection? How aggressively do VMs do this kind of thing? Overall, I think am trying to understand whether thread-local means memory that is physically accessible by only one CPU or if there is logical thread-local heap partitioning done by the VM? Any links to presentations or documentation would be immensely helpful. I have spent time researching this, and although I have found lots of nice literature, I haven't been able to satisfy my curiosity regarding the different situations & definitions of thread-local memory. Thanks very much.

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  • Generate a set of strings with maximum edit distance

    - by Kevin Jacobs
    Problem 1: I'd like to generate a set of n strings of fixed length m from alphabet s such that the minimum Levenshtein distance (edit distance) between any two strings is greater than some constant c. Obviously, I can use randomization methods (e.g., a genetic algorithm), but was hoping that this may be a well-studied problem in computer science or mathematics with some informative literature and an efficient algorithm or three. Problem 2: Same as above except that adjacent characters cannot repeat; the i'th character in each string may not be equal to the i+1'th character. E.g., 'CAT', 'AGA' and 'TAG' are allowed, 'GAA', 'AAT', and 'AAA' are not. Background: The basis for this problem is bioinformatic and involves designing unique DNA tags that can be attached to biologically derived DNA fragments and then sequenced using a fancy second generation sequencer. The goal is to be able to recognize each tag, allowing for random insertion, deletion, and substitution errors. The specific DNA sequencing technology has a relatively low error rate per base (~1%), but is less precise when a single base is repeated 2 or more times (motivating the additional constraints imposed in problem 2).

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  • Runtime Exception when using Custom Healthmonitoring event in medium trust

    - by Elementenfresser
    Hi, I'm using custom healthmonitoring events in ASP.NET We recently moved to a new server with default High Trust Permissions. Literature says that healthmonitoring and custom events should work under Medium or higher trust (http://msdn.microsoft.com/en-us/library/bb398933.aspx). Problem is it doesn't. In less than high trust I get a SecurityException saying The application attempted to perform an operation not allowed by the security policy It works in Full trust or when I remove the inheritance of System.Web.Management.WebErrorEvent. Any suggestions anyone? Here is the super simple code behind with a custom event defined: public partial class Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { try { CallCustomEvent(); } catch (Exception ex) { Response.Write(ex.Message); throw ex; } } /// <summary> /// this metho is never called due to lacking permissions... /// </summary> private void CallCustomEvent() { try { //do something useful here } catch (Exception) { //code to instantiate the forbidden inheritance... WebBaseEvent.Raise(new CustomEvent()); } } } /// <summary> /// custom error inheriting WebErrorEvent which is not allowed in high trust? can't believe that... /// </summary> public class CustomEvent : WebErrorEvent { public CustomEvent() : base("test", HttpContext.Current.Request, 100001, new ApplicationException("dummy")) { } } and the Web Config excerpt for high trust: <system.web> <trust level="High" originUrl="" />

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  • Word characteristics tags

    - by theBlinker
    I want to do a riddle AI chatbot for my AI class. So i figgured the input to the chatbot would be : Something like : "It is blue, and it is up, but it is not the ceiling" Translation : <Object X> <blue> <up> <!ceiling> </Object X> (Answer : sky?) So Input is a set of characteristics (existing \ not existing in the object), output is a matched, most likely object. The domain will be limited to a number of objects, i could input all attributes myself, but i was thinking : How could I programatically build a database of characteristics for a word? Is there such a database available? How could i tag a word, how could i programatically find all it's attributes? I was thinking on crawling wikipedia, or some forum, but i can't see it build any reliable word tag database. Any ideas on how i could achieve such a thing? Any ideas on some literature on the subject? Thank you

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  • Thread-safe data structure design

    - by Inso Reiges
    Hello, I have to design a data structure that is to be used in a multi-threaded environment. The basic API is simple: insert element, remove element, retrieve element, check that element exists. The structure's implementation uses implicit locking to guarantee the atomicity of a single API call. After i implemented this it became apparent, that what i really need is atomicity across several API calls. For example if a caller needs to check the existence of an element before trying to insert it he can't do that atomically even if each single API call is atomic: if(!data_structure.exists(element)) { data_structure.insert(element); } The example is somewhat awkward, but the basic point is that we can't trust the result of "exists" call anymore after we return from atomic context (the generated assembly clearly shows a minor chance of context switch between the two calls). What i currently have in mind to solve this is exposing the lock through the data structure's public API. This way clients will have to explicitly lock things, but at least they won't have to create their own locks. Is there a better commonly-known solution to these kinds of problems? And as long as we're at it, can you advise some good literature on thread-safe design? EDIT: I have a better example. Suppose that element retrieval returns either a reference or a pointer to the stored element and not it's copy. How can a caller be protected to safely use this pointer\reference after the call returns? If you think that not returning copies is a problem, then think about deep copies, i.e. objects that should also copy another objects they point to internally. Thank you.

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  • npgsql Leaking Postgres DB Connections: Way to monitor connections?

    - by Alan
    Background: I'm moving my application from npgsql v1 to npgsql v2.0.9. After a few minutes of running my application, I get a System.Exception: Timeout while getting a connection from the pool. The web claims that this is due to leaking connections (opening a db connection, but not properly closing them). So I'm trying to diagnose leaking postgres connections in npgsql. From the various web literature around; one way to diagnose leaking connections is to setup logging on npgsql, and look for the leaking connection warning message in the log. Problem is, I'm not seeing this message in the logs anywhere. I also found utility that monitors npgsql connections, but it's unstable and crashes. So I'm left manually inspecting code. For everyplace that creates an npgsql connection, there is a finally block disposing of it. For everyplace that opens a datareader, CommandBehavior.CloseConnection is used (and the datareader is disposed). Any other places to check or can someone recommend a way to look for leaking pool connections?

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  • Alignment in assembly

    - by jena
    Hi, I'm spending some time on assembly programming (Gas, in particular) and recently I learned about the align directive. I think I've understood the very basics, but I would like to gain a deeper understanding of its nature and when to use alignment. For instance, I wondered about the assembly code of a simple C++ switch statement. I know that under certain circumstances switch statements are based on jump tables, as in the following few lines of code: .section .rodata .align 4 .align 4 .L8: .long .L2 .long .L3 .long .L4 .long .L5 ... .align 4 aligns the following data on the next 4-byte boundary which ensures that fetching these memory locations is efficient, right? I think this is done because there might be things happening before the switch statement which caused misalignment. But why are there actually two calls to .align? Are there any rules of thumb when to call .align or should it simply be done whenever a new block of data is stored in memory and something prior to this could have caused misalignment? In case of arrays, it seems that alignment is done on 32-byte boundaries as soon as the array occupies at least 32 byte. Is it more efficient to do it this way or is there another reason for the 32-byte boundary? I'd appreciate any explanation or hint on literature.

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  • Security Exception when using Custom ASP.NET Healthmonitoring event in medium trust

    - by Elementenfresser
    Hi, I'm using custom healthmonitoring events in ASP.NET We recently moved to a new server with default High Trust Permissions. Literature says that healthmonitoring and custom events should work under Medium or higher trust (http://msdn.microsoft.com/en-us/library/bb398933.aspx). Problem is - it doesn't. In less than full trust I get a SecurityException saying The application attempted to perform an operation not allowed by the security policy It works in Full trust or when I remove the inheritance of System.Web.Management.WebErrorEvent. Any suggestions anyone? Here is the super simple code behind with a custom event defined: public partial class Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { try { CallCustomEvent(); } catch (Exception ex) { Response.Write(ex.Message); throw ex; } } /// <summary> /// this metho is never called due to lacking permissions... /// </summary> private void CallCustomEvent() { try { //do something useful here } catch (Exception) { //code to instantiate the forbidden inheritance... WebBaseEvent.Raise(new CustomEvent()); } } } /// <summary> /// custom error inheriting WebErrorEvent which is not allowed in high trust? can't believe that... /// </summary> public class CustomEvent : WebErrorEvent { public CustomEvent() : base("test", HttpContext.Current.Request, 100001, new ApplicationException("dummy")) { } } and the Web Config excerpt for high trust: <system.web> <trust level="High" originUrl="" />

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  • Calculating distance from latitude, longitude and height using a geocentric co-ordinate system

    - by Sarge
    I've implemented this method in Javascript and I'm roughly 2.5% out and I'd like to understand why. My input data is an array of points represented as latitude, longitude and the height above the WGS84 ellipsoid. These points are taken from data collected from a wrist-mounted GPS device during a marathon race. My algorithm was to convert each point to cartesian geocentric co-ordinates and then compute the Euclidean distance (c.f Pythagoras). Cartesian geocentric is also known as Earth Centred Earth Fixed. i.e. it's an X, Y, Z co-ordinate system which rotates with the earth. My test data was the data from a marathon and so the distance should be very close to 42.26km. However, the distance comes to about 43.4km. I've tried various approaches and nothing changes the result by more than a metre. e.g. I replaced the height data with data from the NASA SRTM mission, I've set the height to zero, etc. Using Google, I found two points in the literature where lat, lon, height had been transformed and my transformation algorithm is matching. What could explain this? Am I expecting too much from Javascript's double representation? (The X, Y, Z numbers are very big but the differences between two points is very small). My alternative is to move to computing the geodesic across the WGS84 ellipsoid using Vincenty's algorithm (or similar) and then calculating the Euclidean distance with the two heights but this seems inaccurate. Thanks in advance for your help!

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  • Drupal 6 - I am using drupal_execute to insert a CCK node into my site. Everything is working excep

    - by rdurbin
    $form_state['values']['field_prx_mp3_labels'][0][value] = $mp3_labels; $form_state['values']['taxonomy'][0][value] = array('tags'=>array('1'=>'Music')); $errs = drupal_execute('prx_content_node_form', $form_state, (object) $nodeTmp); This is a Drupal 6 site. I am using drupal_execute to create a node programatically. The first line is working for field_prx_mp3_labels. The second (for taxonomy) is not. Here is what my select on the node add for my cck looks like: <select name="taxonomy[2][]" multiple="multiple" class="form-select" id="edit-taxonomy-2" size="9"><option value="">- None -</option><option value="5">Music</option><option value="6">-Rock/Pop</option><option value="7">-Jazz/Blues</option><option value="8">-Classical</option><option value="9">-Music Documentaries</option><option value="10">-Festivals/Concerts</option><option value="11">Arts</option><option value="19">-Literature</option><option value="12">Nature</option><option value="13">History</option><option value="15">-Music</option><option value="14">Culture</option><option value="17">-American Indian</option><option value="18">-Latino</option><option value="16">-Youth Perspective</option></select> I have tried many many variations for line 2 (relating to the taxonomy). This comment seemed close but it hasn't worked for me: http://drupal.org/node/178506#comment-1155576 Thanks!

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  • JavaScript window object element properties

    - by Timothy
    A coworker showed me the following code and asked me why it worked. <span id="myspan">Do you like my hat?</span> <script type="text/javascript"> var spanElement = document.getElementById("myspan"); alert("Here I am! " + spanElement.innerHTML + "\n" + myspan.innerHTML); </script> I explained that a property is attached to the window object with the name of the element's id when the browser parses the document which then contains a reference to the appropriate dom node. It's sort of as if window.myspan = document.getElementById("myspan") is called behind the scenes as the page is being rendered. The ensuing discussion we had raised a few of questions: The window object and most of the DOM are not part of the official JavaScript/ECMA standards, but is the above behavior documented in any other official literature, perhaps browser-related? The above works in a browser (at least the main contenders) because there is a window object, but fails in something like rhino. Is writing code that relys on this considered bad practice because it makes too many assumptions about the execution environment? Are there any browsers in which the above would fail, or is this considered standard behavior across the board? Does anyone here know the answers to those questions and would be willing to enlighten me? I tried a quick internet search, but I admit I'm not sure how to even properly phrase the query. Pointers to references and documentation are welcome.

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  • Standard term for a thread I/O reorder buffer?

    - by Crashworks
    I have a case where many threads all concurrently generate data that is ultimately written to one long, serial file. I need to somehow serialize these writes so that the file gets written in the right order. ie, I have an input queue of 2048 jobs j0..jn, each of which produces a chunk of data oi. The jobs run in parallel on, say, eight threads, but the output blocks have to appear in the file in the same order as the corresponding input blocks — the output file has to be in the order o0o1o2... The solution to this is pretty self evident: I need some kind of buffer that accumulates and writes the output blocks in the correct order, similar to a CPU reorder buffer in Tomasulo's algorithm, or to the way that TCP reassembles out-of-order packets before passing them to the application layer. Before I go code it, I'd like to do a quick literature search to see if there are any papers that have solved this problem in a particularly clever or efficient way, since I have severe realtime and memory constraints. I can't seem to find any papers describing this though; a Scholar search on every permutation of [threads, concurrent, reorder buffer, reassembly, io, serialize] hasn't yielded anything useful. I feel like I must just not be searching the right terms. Is there a common academic name or keyword for this kind of pattern that I can search on?

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  • Dimension Reduction in Categorical Data with missing values

    - by user227290
    I have a regression model in which the dependent variable is continuous but ninety percent of the independent variables are categorical(both ordered and unordered) and around thirty percent of the records have missing values(to make matters worse they are missing randomly without any pattern, that is, more that forty five percent of the data hava at least one missing value). There is no a priori theory to choose the specification of the model so one of the key tasks is dimension reduction before running the regression. While I am aware of several methods for dimension reduction for continuous variables I am not aware of a similar statical literature for categorical data (except, perhaps, as a part of correspondence analysis which is basically a variation of principal component analysis on frequency table). Let me also add that the dataset is of moderate size 500000 observations with 200 variables. I have two questions. Is there a good statistical reference out there for dimension reduction for categorical data along with robust imputation (I think the first issue is imputation and then dimension reduction)? This is linked to implementation of above problem. I have used R extensively earlier and tend to use transcan and impute function heavily for continuous variables and use a variation of tree method to impute categorical values. I have a working knowledge of Python so if something is nice out there for this purpose then I will use it. Any implementation pointers in python or R will be of great help. Thank you.

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