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  • Loop a formula in excel VBA

    - by CEMG
    I am trying to loop a formula in Column "D" until Column "B" doesn't have any more data. The formula I am adding to Column "D" is : IF(ISNUMBER(C5),C5,IF(C5A5/3+OFFSET(C5,-1,0)) ,IF(C5<C6,((OFFSET(C5,1,0)-OFFSET(C5,-2,0))(A5/3)+OFFSET(C5,-2,0)),""))) So the result I want in Column "D" once the macro is run is this: A B C D 3 May-10 78.0000 78.00000 1 Jun-10 52.06667 2 Jul-10 26.13333 3 Aug-10 0.2000 0.20000 1 Sep-10 0.21393 2 Oct-10 0.22786 3 Nov-10 0.2418 0.24179 1 Dec-10 0.26640 2 Jan-11 0.29102 3 Feb-11 0.3156 0.31563 1 Mar-11 0.34821 2 Apr-11 0.38080 3 May-11 0.4134 0.41338 1 Jun-11 0.44992 2 Jul-11 0.48646 3 Aug-11 0.5230 0.52300 1 Sep-11 0.56440 2 Oct-11 0.60580 3 Nov-11 0.6472 0.64720 1 Dec-11 0.43147 If someone can help me at what I am doing wrong with the VBA codes I would greatly appreciated. My CODES are the following: Sub IsNumeric() // first logic: IF(ISNUMBER(C6),C6 // If Application.IsNumber(Range("c5").Value) Then Range("d5").Value = Range("C5").Value // second logic: IF(C6 ElseIf Range("c6").Value < Range("c5").Value Then Range("d6").Value = Range("c6").Offset(2, 0).Value - Range("c6").Offset(-1, 0).Value * (Range("a6").Value / 3) + Range("c6").Offset(-1, 0).Value // third logic: IF(C6<C7,((OFFSET(C6,1,0)-OFFSET(C6,-2,0))*(A6/3)+OFFSET(C6,-2,0)),""))) // ElseIf Range("c6").Value < Range("c7").Value Then Range("d6").Value = (Range("c6").Offset(1, 0).Select) - Range("c6").Offset(-2, 0).Select * (Range("a6").Select / 3) + Range("c6").Offset(-2, 0).Select Else Range("d6").Value = "" End If End Sub

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  • Can't get RDFlib to work on windows

    - by john
    I have installed RDFlib 3.0 and everything that is needed, but when I run the following code I get an error. The code below is from: http://code.google.com/p/rdflib/wiki/IntroSparql. I have tried for hours to fix this but with no success. Can please someone help? import rdflib rdflib.plugin.register('sparql', rdflib.query.Processor, 'rdfextras.sparql.processor', 'Processor') rdflib.plugin.register('sparql', rdflib.query.Result, 'rdfextras.sparql.query', 'SPARQLQueryResult') from rdflib import ConjunctiveGraph g = ConjunctiveGraph() g.parse("http://bigasterisk.com/foaf.rdf") g.parse("http://www.w3.org/People/Berners-Lee/card.rdf") from rdflib import Namespace FOAF = Namespace("http://xmlns.com/foaf/0.1/") g.parse("http://danbri.livejournal.com/data/foaf") [g.add((s, FOAF['name'], n)) for s,_,n in g.triples((None, FOAF['member_name'], None))] for row in g.query( """SELECT ?aname ?bname WHERE { ?a foaf:knows ?b . ?a foaf:name ?aname . ?b foaf:name ?bname . }""", initNs=dict(foaf=Namespace("http://xmlns.com/foaf/0.1/"))): print "%s knows %s" % row The error I get is: Traceback (most recent call last): File "...", line 18 in <module> initNs=dict(foaf=Namespace("http://xmlns.com/foaf/0.1/"))): TypeError: query() got an unexpected keyword argument 'initNS'

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  • Reverse search in Hibernate Search

    - by Javi
    Hello, I'm using Hibernate Search (which uses Lucene) for searching some Data I have indexed in a directory. It works fine but I need to do a reverse search. By reverse search I mean that I have a list of queries stored in my database I need to check which one of these queries match with a Data object each time Data Object is created. I need it to alert the user when a Data Object matches with a Query he has created. So I need to index this single Data Object which has just been created and see which queries of my list has this object as a result. I've seen Lucene MemoryIndex Class to create an index in memory so I can do something like this example for every query in a list (though iterating in a Java list of queries would not be very efficient): //Iterating over my list<Query> MemoryIndex index = new MemoryIndex(); //Add all fields index.addField("myField", "myFieldData", analyzer); ... QueryParser parser = new QueryParser("myField", analyzer); float score = index.search(query); if (score > 0.0f) { System.out.println("it's a match"); } else { System.out.println("no match found"); } The problem here is that this Data Class has several Hibernate Search Annotations @Field,@IndexedEmbedded,... which indicated how fields should be indexed, so when I invoke index() method on the FullTextEntityManager instance it uses this information to index the object in the directory. Is there a similar way to index it in memory using this information? Is there a more efficient way of doing this reverse search? Thanks

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  • Spider a Website and Return URLs Only

    - by Rob Wilkerson
    I'm not quite sure how best to define/articulate this, but I'm looking for a way to pseudo-spider a website. The key is that I don't actually want the content, but rather a simple list of URIs. I can get reasonably close to this idea with Wget using the --spider option, but when piping that output through a grep, I can't seem to find the right magic to make it work: wget --spider --force-html -r -l1 http://somesite.com | grep 'Saving to:' The grep filter seems to have absolutely no affect on the wget output. Have I got something wrong or is there another tool I should try that's more geared towards providing this kind of limited result set? Thanks. UPDATE So I just found out offline that, by default, wget writes to stderr. I missed that in the man pages (in fact, I still haven't found it if it's in there). Once I piped the return to stdout, I got closer to what I need: wget --spider --force-html -r -l1 http://somesite.com 2>&1 | grep 'Saving to:' I'd still be interested in other/better means for doing this kind of thing, if any exist.

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  • IIS Restrict Access to Directory for table of users

    - by Dave
    I am trying to restrict access to files in a directory and it's sub directories based user rights. My user rights are stored in an MS SQL database in a custom format, however it is easy to query the list of users with rights to this directory. I need to know how to apply this to a web config on the server to authenticate against a query of a database table to determine if the username is authenticated and allowed to view the file. Of course if they are not they should be blocked / given a 404. I am using IIS and ASP.Net MVC3 with a form based security as opposed to the built in roles and responsibilities that was custom made for us and that works great. There are over 10k users tied to this non-Active Directory authentication so I am not planning to change my authentication type so please don't go there. It is not my decision on the choice of platform, or I would have gone with a LAMP server and been done with this. Edit 11-13-2012 @ 8:57a: In the web config can you put the result of an SQL query?

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  • retrieving multiple versions through API through hbase

    - by sammy
    hello , this is a continuation of my previous question where id used hbase shell.. http://stackoverflow.com/questions/3024417/facing-problems-while-updating-rows-in-hbase i tried the same with API.. im not able to figure out how to retrieve all versions , iterate and print their values for a specific row... i've spending hours reading... please help me out... Scan s = new Scan(Bytes.toBytes("row1")); s.addColumn(Bytes.toBytes("column"),Bytes.toBytes("address")); SETTING RANGE FOR THE VERSIONS s.setTimeRange(0L,6L); ResultScanner scanner = table.getScanner(s); for (Result r : scanner) { for(KeyValue kv : r.sorted()) { System.out.println("To"+kv.getTimestamp()); System.out.println("from "+Bytes.toString(kv.getKey())); System.out.println("To "+Bytes.toString(kv.getValue())); } scanner.close(); } here im intending to print all versions of the column..... but it gives the most recent one... im stuck here...

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  • put link on table row or any other way to put link

    - by air
    i have one php code for button creation for($i=1;$i<=$n;$i++) { $row=mysql_fetch_array($result); if($row['btn_color']==1) $btbg="side-button5.png"; if($row['btn_color']==2) $btbg="side-button6.png"; if($row['btn_color']==3) $btbg="side-button7.png"; if($row['btn_color']==4) ?> <br> <table width="200" height="50" border="0" cellpadding="0" cellspacing="0"> <tr> <td background="images/<?php echo $btbg ; ?>" style="background-repeat:no-repeat"><table width="100%" border="0" cellspacing="0" cellpadding="0"> <tr> <td height="66"> <div align="center" class="buttonside"> <p> <a class="buttonside" href="vpa.php?pgid=<?php echo $row['page_id']; ?>"> <?php echo $row['btn_text']?></p> </a> </div> </td> </tr> </table> </td> </tr> </table> <?php } ?> this code is working fine but the link is on text, i want to put link on full button(background) Thanks

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  • How to replace pairs of strings in two files to identical IDs?

    - by Péter Török
    Sorry if the title is not very intelligible, I couldn't come up with anything better. Hopefully my explanation is clear enough: I have a pair of rather large log files with very similar content, except that some strings are different between the two. A couple of examples: UnifiedClassLoader3@19518cc | UnifiedClassLoader3@d0357a JBossRMIClassLoader@13c2d7f | JBossRMIClassLoader@191777e That is, wherever the first file contains UnifiedClassLoader3@19518cc, the second contains UnifiedClassLoader3@d0357a, and so on. [Update] There are about 40 distinct pairs of such identifiers.[/Update] I want to replace these with identical IDs so that I can spot the really important differences between the two files. I.e. I want to replace all occurrences of both UnifiedClassLoader3@19518cc in file1 and UnifiedClassLoader3@d0357a in file2 with UnifiedClassLoader3@1; all occurrences of both JBossRMIClassLoader@13c2d7f in file1 and JBossRMIClassLoader@191777e in file2 with JBossRMIClassLoader@2 etc. Using the Cygwin shell, so far I managed to list all different identifiers occurring in one of the files with grep -o -e 'ClassLoader[0-9]*@[0-9a-f][0-9a-f]*' file1.log | sort | uniq However, now the original order is lost, so I don't know which is the pair of which ID in the other file. With grep -n I can get the line number, so the sort would preserve the order of appearance, but then I can't weed out the duplicate occurrences. Unfortunately grep can not print only the first match of a pattern. I figured I could save the list of identifiers produced by the above command into a file, then iterate over the patterns in the file with grep -n | head -n 1, concatenate the results and sort them again. The result would be something like 2 ClassLoader3@19518cc 137 ClassLoader@13c2d7f 563 ClassLoader3@1267649 ... Then I could (either manually or with sed itself) massage this into a sed command like sed -e 's/ClassLoader3@19518cc/ClassLoader3@2/g' -e 's/ClassLoader@13c2d7f/ClassLoader@137/g' -e 's/ClassLoader3@1267649/ClassLoader3@563/g' file1.log > file1_processed.log and similarly for file2. However, before I start, I would like to verify that my plan is the simplest possible working solution to this. Is there any flaw in this approach? Is there a simpler way?

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  • Image processing on bifurcation diagram to get small eps size

    - by yCalleecharan
    Hello, I'm producing bifurcation diagrams (which are normally used in nonlinear dynamics). These diagrams identify abrupt changes in topologies due to stability changes. These abrupt changes occur as one or more parameters pass through some critical value(s). An example is here: http://en.wikipedia.org/wiki/File:LogisticMap_BifurcationDiagram.png On the above figure, some image processing has been done so as to make the plot more visually pleasant. A bifurcation diagram usually contains hundreds of thousands of points and the resulting eps file can become very big. Journal submission in the LaTeX format require that figures are to be submitted in the eps format. In my case one of such figures can result in about 6 MB in Matlab and even much more in Gnuplot. For the example in the above figure, 100,000 x values are calculated for each r and one can imagine that the resulting eps file would be huge. The site however explains some image processing that makes the plot more visually pleasing. Can anyone explain to me stepwise how go about? I can't understand the explanation provided in the "summary" section. Will the resulting image processing also reduce the figure size? Furthermore, any tips on reducing the file size of such a huge eps figure? Thanks a lot...

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  • SQLite transaction doesn't work as expected

    - by troll
    I prepared 2 files, "1.php" and "2.php". "1.php" is like this. <?php $dbh = new PDO('sqlite:test1'); $dbh->beginTransaction(); print "aaa<br>"; sleep(55); $dbh->commit(); print "bbb"; ?> and "2.php" is like this. <?php $dbh = new PDO('sqlite:test1'); $dbh->beginTransaction(); print "ccc<br>"; $dbh->commit(); print "ddd"; ?> and I excute "1.php". It starts a transaction and waits 55 seconds. So when I immediately excute "2.php", my expectation is this: "1.php" is getting transaction and "1" holds a database lock "2" can not begin a transaction "2" can not get database lock so "2" have to wait 55 seconds BUT, but the test went another way. When I excute "2",then "2" immediately returned it's result "2" did not wait so I have to think that "1" could not get transaction, or could not get database lock. Can anyone help?

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  • How to change scope data in controller?

    - by Derooie
    I am a real newbie at angular. I created something now which will let me retrieve and add items via angular and get/put them in mongodb. I use express and mongoose in the app The question is, how can i modify the data before it reaches the DOM in the controller. In this example i have created a way to retrieve data, and i get it exactly as it is stored in mongodb. What i would like is that the field where i store 1 or 0 in the database, to be shown as text. So if mongo has a value 1 i get "the value in mongo is 1" and when the field has a value of 0 get "the value is zero". (just as an example, i like other texts, but it illustrate what i want) I post my controller, html and current output. Any help would be appreciated. Controller function getGuests($scope, $http) { $scope.formData = {}; $http.get('/api/guests') .success(function(data) { $scope.x = data; }) .error(function(data) { console.log('Error: ' + data); }); } HTML <div ng-controller="getGuests"> <div ng-repeat="guest in x"> {{ guest.voornaam }} {{ guest.aanwezig }} </div> </div> The current scope output, what i see in HTML. I like to change only the value of "aanwezig" in case the value of aanwezig is 0 or 1. firstname1 1 firstname2 0 Something else, but would be great to learn, is how i can do a specific mongodb query by the push of a button and get that result.

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  • oracle plsql select pivot without dynamic sql to group by

    - by kayhan yüksel
    To whom it may respond to, We would like to use SELECT function with PIVOT option at a 11g r2 Oracle DBMS. Our query is like : "select * from (SELECT o.ship_to_customer_no, ol.item_no,ol.amount FROM t_order o, t_order_line ol WHERE o.NO = ol.order_no and ol.item_no in (select distinct(item_no) from t_order_line)) pivot --xml ( SUM(amount) FOR item_no IN ( select distinct(item_no) as item_no_ from t_order_line));" As can be seen, XML is commented out, if run as PIVOT XML it gives the correct output in XML format, but we are required to get the data as unformatted pivot data, but this sentence throws error : ORA-00936: missing expression Any resolutions or ideas would be welcomed, Best Regards -------------if we can get the result of this to sys_refcursor using execute immediate it will be solved ------------------------ the procedure : PROCEDURE pr_test2 (deneme OUT sys_refcursor) IS v_sql NVARCHAR2 (4000) := ''; TYPE v_items IS TABLE OF NVARCHAR2 (30); v_pivot_items NVARCHAR2 (4000) := ''; BEGIN FOR i IN (SELECT DISTINCT (item_no) AS items FROM t_order_line) LOOP v_pivot_items := ',''' || i.items || '''' || v_pivot_items; END LOOP; v_pivot_items := LTRIM (v_pivot_items, ','); v_sql := 'begin select * from (SELECT o.ship_to_customer_no, ol.item_no,ol.amount FROM t_order o, t_order_line ol WHERE o.NO = ol.order_no and OL.ITEM_NO in (select distinct(item_no) from t_order_line)) pivot --xml ( SUM(amount) FOR item_no IN (' || v_pivot_items || '));end;'; open DENEME for select v_sql from dual; Kayhan YÜKSEL

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  • Delayed_job not executing the perform method but emptying the job queue

    - by James
    I have a fresh rails 3 app, here's my Gemfile: source 'http://rubygems.org' gem 'rails', '3.0.0' gem 'delayed_job' gem 'sqlite3-ruby', :require = 'sqlite3' Here's the class that represents the job that I want to queue: class Me < Struct.new(:something) def perform puts "Hello from me" logger.info "Hello from me" logger.debug "Hello from me" raise Exception.new end end From the console with no workers running: irb(main):002:0> Delayed::Job.enqueue Me.new(1) => #<Delayed::Backend::ActiveRecord::Job id: 7, priority: 0, attempts: 0, handler: "--- !ruby/struct:Me \nsomething: 1\n", last_error: nil, run_at: "2010-12-29 07:24:11", locked_at: nil, failed_at: nil, locked_by: nil, created_at: "2010-12-29 07:24:11", updated_at: "2010-12-29 07:24:11"> Like I mentioned: there are no workers running: irb(main):003:0> Delayed::Job.all => [#<Delayed::Backend::ActiveRecord::Job id: 7, priority: 0, attempts: 0, handler: "--- !ruby/struct:Me \nsomething: 1\n", last_error: nil, run_at: "2010-12-29 07:24:11", locked_at: nil, failed_at: nil, locked_by: nil, created_at: "2010-12-29 07:24:11", updated_at: "2010-12-29 07:24:11">] I start a worker with script/delayed_job run The queue gets emptied: irb(main):006:0> Delayed::Job.all => [] However, nothing happens as a result of the puts, nothing is logged from the logger calls, and no exception is raised. I'd appreciate any help / insight or anything to try.

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  • What can be the reason for Windows error ERROR_DISK_FULL (112) when opening a NTFS alternate data st

    - by ur
    My application writes some bytes of data to an alternate data stream. This works fine on all but one machine (Windows Server 2003 SP2). Instead, CreateFile returns ERROR_DISK_FULL when I try to create an alternate data stream (on the root directory). I don't find the reason for this result, because... There's plenty of space on that drive. The drive is NTFS formatted (due to GetVolumeInformation). The drive supports altenate data streams (due to GetVolumeInformation). Edit: I can provide some more information about what the reason not is: I added many streams on a test system which didn't show the error and wondered if the error might occur. It didn't. Instead after about 2000 Streams with long file names another error occurred and persisted: 1450 (ERROR_NO_SYSTEM_RESOURCES). EDIT: Here is an example for one of the used file names: char szStreamFileName[] = "C:\\:abcdefghijklmnopqrstuvwxyz1234567890abcdefghijklmnoqrstuvwxyz012345"; EDIT: Our customer uses some corporate antivirus software from Avira on this server. Maybe this is the reason (Alternate data streams can be abused by malware).

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  • Raphael.js: Adding a new custom element

    - by Claudia
    I would like to create a custom Raphael element, with custom properties and functions. This object must also contain predefined Raphael objects. For example, I would have a node class, that would contain a circle with text and some other elements inside it. The problem is to add this new object to a set. These demands are needed because non-Raphael objects cannot be added to sets. As a result, custom objects that can contain Raphael objects cannot be used. The code would look like this: var Node = function (paper) { // Coordinates & Dimensions this.x = 0, this.y = 0, this.radius = 0, this.draw = function () { this.entireSet = paper.set(); var circle = paper.circle(this.x, this.y, this.radius); this.circleObj = circle; this.entireSet.push(circle); var text = paper.text(this.x, this.y, this.text); this.entireSet.push(text); } // other functions } var NodeList = function(paper){ this.nodes = paper.set(), this.populateList = function(){ // in order to add a node to the set // the object must be of type Raphael object // otherwise the set will have no elements this.nodes.push(// new node) } this.nextNode = function(){ // ... } this.previousNode = function(){ // ... } }

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

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

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  • What can cause my code to run slower when the server JIT is activated?

    - by durandai
    I am doing some optimizations on an MPEG decoder. To ensure my optimizations aren't breaking anything I have a test suite that benchmarks the entire codebase (both optimized and original) as well as verifying that they both produce identical results (basically just feeding a couple of different streams through the decoder and crc32 the outputs). When using the "-server" option with the Sun 1.6.0_18, the test suite runs about 12% slower on the optimized version after warmup (in comparison to the default "-client" setting), while the original codebase gains a good boost running about twice as fast as in client mode. While at first this seemed to be simply a warmup issue to me, I added a loop to repeat the entire test suite multiple times. Then execution times become constant for each pass starting at the 3rd iteration of the test, still the optimized version stays 12% slower than in the client mode. I am also pretty sure its not a garbage collection issue, since the code involves absolutely no object allocations after startup. The code consists mainly of some bit manipulation operations (stream decoding) and lots of basic floating math (generating PCM audio). The only JDK classes involved are ByteArrayInputStream (feeds the stream to the test and excluding disk IO from the tests) and CRC32 (to verify the result). I also observed the same behaviour with Sun JDK 1.7.0_b98 (only that ist 15% instead of 12% there). Oh, and the tests were all done on the same machine (single core) with no other applications running (WinXP). While there is some inevitable variation on the measured execution times (using System.nanoTime btw), the variation between different test runs with the same settings never exceeded 2%, usually less than 1% (after warmup), so I conclude the effect is real and not purely induced by the measuring mechanism/machine. Are there any known coding patterns that perform worse on the server JIT? Failing that, what options are available to "peek" under the hood and observe what the JIT is doing there?

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  • Rtti data manipulation and consistency in Delphi 2010

    - by Coco
    Has anyone an idea, how I can make TValue using a reference to the original data? In my serialization project, I use (as suggested in XML-Serialization) a generic serializer which stores TValues in an internal tree-structure (similar to the MemberMap in the example). This member-tree should also be used to create a dynamic setup form and manipulate the data. My idea was to define a property for the Data: TDataModel <T> = class {...} private FData : TValue; function GetData : T; procedure SetData (Value : T); public property Data : T read GetData write SetData; end; The implementation of the GetData, SetData Methods: procedure TDataModel <T>.SetData (Value : T); begin FData := TValue.From <T> (Value); end; procedure TDataModel <T>.GetData : T; begin Result := FData.AsType <T>; end; Unfortunately, the TValue.From method always makes a copy of the original data. So whenever the application makes changes to the data, the DataModel is not updated and vice versa if I change my DataModel in a dynamic form, the original data is not affected. Sure I could always use the Data property before and after changing anything, but as I use lot of Rtti inside my DataModel, I do not realy want to do this anytime. Perhaps someone has a better suggestion?

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  • Creating futures using Apple's GCD

    - by jer
    I'm working on a library which implements the actor model on top of Grand Central Dispatch (specifically the C level API libdispatch). Basically a brief overview of my system is as such: Communication happens between actors using messages Multicast communication only (one actor to many actors) Senders and receivers are decoupled from one another using a blackboard where messages are pushed to. Messages are sent in the default queue asynchronously using dispatch_group_async() once a message gets pushed onto the blackboard. I'm trying to implement futures in the language right now, so I've created a new type which holds some information: A group of its own The value being 'returned' However, I have a problem since dispatch_block_t is of type void (^)(void) so it doesn't return anything. So my idea of in my future_new() function of setting up another group which can be used to execute a block returning a result, which I can store in my "value" member in my future_t structure, isn't going to work. The rest of the futures implementation is very clear, except it all depends on being able to get the value into the future back from the actor, acting on the message. When using the library, it would greatly reduce its usefulness if I had to ask users (and myself) to be aware when futures were going to be used by other parts of the system—It just isn't practical. I'm wondering if anyone can think of a way around this?

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  • Avoiding a fork()/SIGCHLD race condition

    - by larry
    Please consider the following fork()/SIGCHLD pseudo-code. // main program excerpt for (;;) { if ( is_time_to_make_babies ) { pid = fork(); if (pid == -1) { /* fail */ } else if (pid == 0) { /* child stuff */ print "child started" exit } else { /* parent stuff */ print "parent forked new child ", pid children.add(pid); } } } // SIGCHLD handler sigchld_handler(signo) { while ( (pid = wait(status, WNOHANG)) > 0 ) { print "parent caught SIGCHLD from ", pid children.remove(pid); } } In the above example there's a race-condition. It's possible for "/* child stuff */" to finish before "/* parent stuff */" starts which can result in a child's pid being added to the list of children after it's exited, and never being removed. When the time comes for the app to close down, the parent will wait endlessly for the already-finished child to finish. One solution I can think of to counter this is to have two lists: started_children and finished_children. I'd add to started_children in the same place I'm adding to children now. But in the signal handler, instead of removing from children I'd add to finished_children. When the app closes down, the parent can simply wait until the difference between started_children and finished_children is zero. Another possible solution I can think of is using shared-memory, e.g. share the parent's list of children and let the children .add and .remove themselves? But I don't know too much about this. EDIT: Another possible solution, which was the first thing that came to mind, is to simply add a sleep(1) at the start of /* child stuff */ but that smells funny to me, which is why I left it out. I'm also not even sure it's a 100% fix. So, how would you correct this race-condition? And if there's a well-established recommended pattern for this, please let me know! Thanks.

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  • SQL using sum to count results of multiple subqueries

    - by asdas
    I have a table with 2 columns: integer and var char. I am given only the integer values but need to do work on the var char (string) values. Given an integer, and a list of other integers (no overlap), I want to find the string for that single integer. Then I want to take that string and do the INSTR command with that string, and all the other strings for all the other integers. Then I want the sum of all the INSTR so the result is one number. So lets say I have int x, and list y=[y0, y1, y2]. I want to do 3 INSTR commands like SUM(INSTR(string for x, string for y0), INSTR(string for x, string for y1), INSTR(string for x, string for y2)) I think im going in the wrong direction, this is what I have. Im not good with sub queries. SELECT SUM ( SELECT INSTR ( SELECT string FROM pages WHERE int=? LIMIT 1, ( SELECT string FROM pages WHERE id=? OR id=? OR id=? LIMIT 3 ) ) )

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  • Strange behaviour with PHP/Pear HTML_Quickform and Firfox 3.6

    - by chessweb
    I am using PHP/Pear HTMLQuickForm and HTMLQuickForm_Controller to do some stuff with HTML-forms. Then I noticed that certain phone numbers would not be displayed even though the data had been loaded correctly. I boiled it down to the following rather strange phenomenons that have me completely baffled: $this->addElement('static', null, 'Telefon:', '04556-8978765'); will just show "Telefon:" in Firefox 3.6. In IE8 I see "Telefon: 04556-8978765" as expected. $this->addElement('static', null, 'Telefon:', '904556-8978765'); displays just "Telefon: 9" in Firefox 3.6 and correctly "Telefon: 904556-8978765" in IE8. On the other hand $this->addElement('static', null, 'Telefon:', '099828-67776554'); shows "Telefon: 099828-67776554" in both browsers. So my question is this: What is so special about the string 04556-8978765 that Firefox 3.6 refuses to render it? And it gets even weirder: The string 0208-23345 and 02232-12345 have the same problem, but when I prefix them with any other character, then unlike 04556-8978765 they are displayed alright. And it is not as if the missing strings are not rendered at all. On page reload I see them for a short time and then they disappear for good. Now try to guess the result of $this->addElement('static', null, 'Telefon:', '04556-8978765'); $this->addElement('static', null, 'Telefon:', '04556-8978765'); Right, it is not Telefon: 04556-8978765 Telefon: 04556-8978765 as expected, but rather Telefon: Telefon: 04556-8978765 Can anybody make any sense of this?

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  • Max Daily Budget exceeded and Billing Status "Changing Daily Budget"

    - by draftpik
    We've exceeded the Max Daily Budget for our app, but we can't increase the budget due to a serious flaw in Google's billing system. Google App Engine and Google Wallet do not have very capable support for multiple sign-in. As a result, I went to change the budget, but it used the wrong Google Wallet account (a different Google Account I was signed in as). I had to go back and try again, but now our GAE app shows the following status: Billing Status: Changing Daily Budget Your account has been locked while we process your budget changes. If you were redirected to Google Checkout but did not complete the process, your settings will remain unchanged. (You will be able to make changes to your budget settings again once the outstanding payment is processed.) Now I'm completely prevented from making any billing changes, our app is shut off (over quota), and I have NOTHING I can do to fix it. This is a seriously fundamental flaw in App Engine's billing system and Google Wallet integration. Has anyone run into this before? Is there a workaround anyone is aware of? Right now, our production app is completely down thanks to this issue. Any help you can offer would be greatly appreciated? If you're from Google and you might be able to help on the backend, our app id is "nhldraftpik". Thanks! Brian

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  • How to trigger the event together on each two deferent class.

    - by XBasic3000
    I have two object class on a single unit, is it posible to trigger the two events? let say the FIRSTCLASS event is fired, The SECONDCLASS also will fired? Assuming...... //{Class 1}------------------------------------------------------------- type TOnEventTrigger = procedure(Sender : Tobject; Value :integer); TMyFirstClass = Class(Tcomponent) private .... public .... OnEventTrigger : TOnEventTrigger read Fevent write Fevent; end; procedure TMyFirstClass.FEvnt(Sender : Tobject; Value :integer); begin // here is normaly triggers the event // if Assigned(OnEventTrigger) then OnEventTrigger(Self,FSomevalue); // POSTMessage(GetForegroundWindow,WM_USER+3,0,0); // this is what i did here to get the result of FSomevalue // but this is not ideal. It work only on focus window. end; //{Class 2}------------------------------------------------------------- type TOnEventTrigger = procedure(Sender : Tobject; Value :integer); TMySecondClass = Class(Tobject) private .... public .... OnEventTrigger : TOnEventTrigger; read Fevent write Fevent; end; procedure TMySecondClass.FEvnt(Sender : Tobject; Value :integer); begin // I wanted here to trigger, whenenver the above is fired // if Assigned(OnEventTrigger) then OnEventTrigger(Self,FSomevalue); end;

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  • FreqTable with random values(#C)

    - by Sef
    Hello, I would like to make a frequency table with random numbers. So i have created a array that generates 11 random values between 0 and 9999. public void FillArrayRandom(int[] T) { Random Rndint = new Random(); for (int i=0; i < T.Length; i++) { T[i] = Rndint.Next(0, 9999); } }/*FillArrayRandom*/ The result i want is something alike this:(bar height up to 21) So this will be a constant. * * * * * * (the highest value will have the largest row/bar) * * * * 0 1 2 3 .....(index value's) 931 6669 10 8899 .... (up to 11 random values) My question is how do i exactly caculate the frequency between those 11 random values? The bars should have a relative relation with each other depending on there frequency. I would only like to use 1 single array in my program (for the generated values). F = (F * 21?) / ...? Really no clue how to obtain the proper results. If a frequency is =21 write * If a frequency is =20 write * If a frequency is =19 write * etc... Regards.

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