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  • How can i create an n-dimensional array in c

    - by shortCircuit
    I was thinking of making a function that would accept the size of array as a parameter and create a n dimensional array. My room-mate took the liberty of making it complex. He said lets write a function that takes n parameters and returns an n-dimensional array using those parameters as the dimensions. Now i realize an one-day and d array is easy to implement with pointers. For 2d array the snippet would be something like (standard way) : int** x; int* temp; x = (int**)malloc(m * sizeof(int*)); temp = (int*)malloc(m*n * sizeof(int)); for (int i = 0; i < m; i++) { x[i] = temp + (i * n); } where the array is of size m*n; But the problem lies how do we find the nested loop parameters for a n-dimensional array? Is there any way to optimize the code?

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  • JSF2: Re-render all components on page that have a given ID, without absolute paths

    - by tlind
    Is there any way in JSF 2.0/PrimeFaces of re-rendering all components (using the PrimeFaces update="id1 id2..." attribute or the <f:ajax render="..."/> tag) that have got a given ID, regardless of whether they are in the same form that contains the button triggering the AJAX re-render or not? For example, I want my button to re-render all sections on a page that visualize the user's current shopping basket. Right now, I always have to specify the absolute path to the components that I want to get updated, e.g. update=":header:basket :left-sidebar:menu:basket" which is rather impractical if the structure of the page changes (besides, I have not been able to figure out the correct path for one of these components). I already tried to implement a custom EL function like this, which traverses the component tree: update="{utilBean.findAllComponentsMatchingId('basket')}" but at the time that function is evaluated, apparently not the entire component tree has been set up as it doesn't contain the components I am looking for. How can I deal with this? There certainly must be an easy way of doing AJAX-based updates of sections of the page that are not part of the current <h:form>? Thanks!

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  • C++ arrays as parameters, EDIT: now includes variable scoping

    - by awshepard
    Alright, I'm guessing this is an easy question, so I'll take the knocks, but I'm not finding what I need on google or SO. I'd like to create an array in one place, and populate it inside a different function. I define a function: void someFunction(double results[]) { for (int i = 0; i<100; ++i) { for (int n = 0; n<16; ++n) //note this iteration limit { results[n] += i * n; } } } That's an approximation to what my code is doing, but regardless, shouldn't be running into any overflow or out of bounds issues or anything. I generate an array: double result[16]; for(int i = 0; i<16; i++) { result[i] = -1; } then I want to pass it to someFunction someFunction(result); When I set breakpoints and step through the code, upon entering someFunction, results is set to the same address as result, and the value there is -1.000000 as expected. However, when I start iterating through the loop, results[n] doesn't seem to resolve to *(results+n) or *(results+n*sizeof(double)), it just seems to resolve to *(results). What I end up with is that instead of populating my result array, I just get one value. What am I doing wrong? EDIT Oh fun, I have a typo: it wasn't void someFunction(double results[]). It was: void someFunction(double result[])... So perhaps this is turning into a scoping question. If my double result[16] array is defined in a main.cpp, and someFunction is defined in a Utils.h file that's included by the main.cpp, does the result variable in someFunction then wreak havoc on the result array in main?

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  • How to get attribute value using SelectSingleNode in C#?

    - by Nano HE
    Hello. I am parsing a xml document, I need find out the gid (an attribute) value (3810). Based on SelectSingleNode(). I found it is not easy to find the attribute name and it's value. Can I use this method or I must switch to other way. Attached my code. How can I use book obj to get the attribute value3810 for gid. Thank you. My test.xml file as below <?xml version="1.0"?> <root> <VersionInfo date="2007-11-28" version="1.0.0.2"/> <Attributes> <AttrDir name="EFEM" DirID="1"> <AttrDir name="Aligner" DirID="2"> <AttrDir name="SequenceID" DirID="3"> <AttrObj text="Slot01" gid="3810" unit="" scale="1"/> <AttrObjCount value="1"/> </AttrDir> </AttrDir> </AttrDir> </Attributes> </root> I wrote the test.cs as below public class Sample { public static void Main() { XmlDocument doc = new XmlDocument(); doc.Load("test.xml"); XmlNode book; XmlNode root = doc.DocumentElement; book = root.SelectSingleNode("Attributes[AttrDir[@name='EFEM']/AttrDir[@name='Aligner']/AttrDir[@name='SequenceID']/AttrObj[@text='Slot01']]"); Console.WriteLine("Display the modified XML document...."); doc.Save(Console.Out); } }

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  • Counting a cell up per Objects

    - by Auro
    hey i got a problem once again :D a little info first: im trying to copy data from one table to an other table(structure is the same). now one cell needs to be incremented, beginns per group at 1 (just like a histroy). i have this table: create table My_Test/My_Test2 ( my_Id Number(8,0), my_Num Number(6,0), my_Data Varchar2(100)); (my_Id, my_Num is a nested PK) if i want to insert a new row, i need to check if the value in my_id already exists. if this is true then i need to use the next my_Num for this Id. i have this in my Table: My_Id My_Num My_Data 1 1 'test1' 1 2 'test2' 2 1 'test3' if i add now a row for my_Id 1, the row would look like this: i have this in my Table: My_Id My_Num My_Data 1 3 'test4' this sounds pretty easy ,now i need to make it in a SQL and on SQL Server i had the same problem and i used this: Insert Into My_Test (My_Id,My_Num,My_Data) SELECT my_Id, ( SELECT CASE ( CASE MAX(a.my_Num) WHEN NULL THEN 0 Else Max(A.My_Num) END) + b.My_Num WHEN NULL THEN 1 ELSE ( CASE MAX(a.My_Num) WHEN NULL THEN 0 Else Max(A.My_Num) END) + b.My_Num END From My_Test A where my_id = 1 ) ,My_Data From My_Test2 B where my_id = 1; this Select gives null back if no Rows are found in the subselect is there a way so i could use max in the case? and if it give null back it should use 0 or 1? greets Auro

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  • How can I pivot these key+values rows into a table of complete entries?

    - by CodexArcanum
    Maybe I demand too much from SQL but I feel like this should be possible. I start with a list of key-value pairs, like this: '0:First, 1:Second, 2:Third, 3:Fourth' etc. I can split this up pretty easily with a two-step parse that gets me a table like: EntryNumber PairNumber Item 0 0 0 1 0 First 2 1 1 3 1 Second etc. Now, in the simple case of splitting the pairs into a pair of columns, it's fairly easy. I'm interested in the more advanced case where I might have multiple values per entry, like: '0:First:Fishing, 1:Second:Camping, 2:Third:Hiking' and such. In that generic case, I'd like to find a way to take my 3-column result table and somehow pivot it to have one row per entry and one column per value-part. So I want to turn this: EntryNumber PairNumber Item 0 0 0 1 0 First 2 0 Fishing 3 1 1 4 1 Second 5 1 Camping Into this: Entry [1] [2] [3] 0 0 First Fishing 1 1 Second Camping Is that just too much for SQL to handle, or is there a way? Pivots (even tricky dynamic pivots) seem like an answer, but I can't figure how to get that to work.

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  • How to control the "flow" of an ASP.NET MVC (3.0) web app that relies on Facebook membership, with Facebook C# SDK?

    - by Chad
    I want to totally remove the standard ASP.NET membership system and use Facebook only for my web app's membership. Note, this is not a Facebook canvas app question. Typically, in an ASP.NET app you have some key properties & methods to control the "flow" of an app. Notably: Request.IsAuthenticated, [Authorize] (in MVC apps), Membership.GetUser() and Roles.IsUserInRole(), among others. It looks like [FacebookAuthorize] is equivalent to [Authorize]. Also, there's some standard work I do across all controllers in my site. So I built a BaseController that overrides OnActionExecuting(FilterContext). Typically, I populate ViewData with the user's profile within this action. Would performance suffer if I made a call to fbApp.Get("me") in this action? I use the Facebook Javascript SDK to do registration, which is nice and easy. But that's all client-side, and I'm having a hard time wrapping my mind around when to use client-side facebook calls versus server-side. There will be a point when I need to grab the user's facebook uid and store it in a "profile" table along with a few other bits of data. That would probably be best handled on the return url from the registration plugin... correct? On a side note, what data is returned from fbApp.Get("me")?

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  • Stop writing blank line at the end of CSV file (using MATLAB)

    - by Grant M.
    Hello all ... I'm using MATLAB to open a batch of CSV files containing column headers and data (using the 'importdata' function), then I manipulate the data a bit and write the headers and data to new CSV files using the 'dlmwrite' function. I'm using the '-append' and 'newline' attributes of 'dlmwrite' to add each line of text/data on a new line. Each of my new CSV files has a blank line at the end, whereas this blank line was not there before when I read in the data ... and I'm not using 'newline' on my final call of 'dlmwrite'. Does anyone know how I can keep from writing this blank line to the end of my CSV files? Thanks for your help, Grant EDITED 5/18/10 1:35PM CST - Added information about code and text file per request ... you'll notice after performing the procedure below that there appears to be a carriage return at the end of the last line in the new text file. Consider a text file named 'textfile.txt' that looks like this: Column1, Column2, Column3, Column4, Column 5 1, 2, 3, 4, 5 1, 2, 3, 4, 5 1, 2, 3, 4, 5 1, 2, 3, 4, 5 1, 2, 3, 4, 5 Here's a sample of the code I am using: % import data importedData = importdata('textfile.txt'); % manipulate data importedData.data(:,1) = 100; % store column headers into single comma-delimited % character array (for easy writing later) columnHeaders = importedData.textdata{1}; for counter = 2:size(importedData.textdata,2) columnHeaders = horzcat(columnHeaders,',',importedData.textdata{counter}); end % write column headers to new file dlmwrite('textfile_updated.txt',columnHeaders,'Delimiter','','newline','pc') % append all but last line of data to new file for dataCounter = 1:(size(importedData.data,2)-1) dlmwrite('textfile_updated.txt',importedData.data(dataCounter,:),'Delimiter',',','newline','pc','-append') end % append last line of data to new file, not % creating new line at end dlmwrite('textfile_updated.txt',importedData.data(end,:),'Delimiter',',','-append')

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  • Connecting grouped dots/points on a scatter plot based on distance

    - by ToNoY
    I have 2 sets of depth point measurements, for example: > a depth value 1 2 2 2 4 3 3 6 4 4 8 5 5 16 40 6 18 45 7 20 58 > b depth value 1 10 10 2 12 20 3 14 35 I want to show both groups in one figure plotted with depth and with different symbols as you can see here plot(a$value, a$depth, type='b', col='green', pch=15) points(b$value, b$depth, type='b', col='red', pch=14) The plot seems okay, but the annoying part is that the green symbols are all connected (though I want connected lines also). I want connection only when one group has a continued data points at 2 m interval i.e. the symbols should be connected with a line from 2 to 8 m (green) and then group B symbols should be connected from 10-14 m (red) and again group A symbols should be connected (green), which means I do NOT want to see the connection between 8 m sample with the 16 m for group A. An easy solution may be dividing the group A into two parts (say, A-shallow and A-deep) and then plotting A-shallow, B, and A-deep separately. But this is completely impractical because I have thousands of data points with hundreds of groups i.e. I have to produce many depth profiles. Therefore, there has to be a way to program so that dots are NOT connected beyond a prescribed frequency/depth interval (e.g. 2 m in this case) for a particular group of samples. Any idea?

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  • EXC_BAD_ACCESS in NSURLConnection: how to debug?

    - by baswell
    I have an iPhone app that downloads URLs. (PDFs to display) Easy: self.conn = [NSURLConnection connectionWithRequest:self.request delegate:self]; where self.conn is a retained property. For specific URLs, this throws EXC_BAD_ACCESS. The URL is valid and is constructed in the same way as URLs that do work. (90% of URLs are fine) These ones work: http://www.airservicesaustralia.com/publications/current/ersa/FAC_YARG_11-Mar-2010.pdf http://www.airservicesaustralia.com/publications/current/ersa/FAC_YARK_11-Mar-2010.pdf These don't: http://www.airservicesaustralia.com/publications/current/ersa/FAC_YAMK_11-Mar-2010.pdf http://www.airservicesaustralia.com/publications/current/ersa/FAC_YATN_11-Mar-2010.pdf Spot the difference? Yeah, me neither. Also no difference in response headers from the server for them. To clarify, the ones that work ALWAYS work, the ones that don't NEVER work. So not some random release/retain issue it seems. For the ones that don't work, none of the methods in my delegate are ever called, it fails hard before that. And with no error message, just EXC_BAD_ACCESS. Sooo.... Any way to debug what is going on inside NSURLConnection?

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  • Releasing from development into production in maven

    - by Bruce
    Hi all, I'm confused about the use of maven in development and production environments - I'm sure it's something simple that I'm missing. Grateful for any help.. I set up maven inside eclipse on my local machine and wrote some software. I really like how it's made things like including dependent jars very easy. So that's my development environment. But now I want to release the project to production on a remote server. I've searched the documentation, but I can't figure out how it's supposed to work or what the maven best practice is.. Are you supposed to: a) Also be running maven on your production environment, and upload all your files to your production environment and rebuild your project there? (Something in me baulks at the idea of rebuilding 'released' code on the production server, so I'm fairly sure this isn't right..) b) use mvn:package to create your jar file and then copy that up to production? (But then what of all those nice dependencies? Isn't there a danger that your tested code is now going to be running against different versions of the dependent jars in the production environment, possibly breaking your code? Or missing a jar..?) c) Something else that I'm not figuring out.. Thanks in advance for any help!

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  • how to delete multiple folders,desktop and start menu shortcut using vbscript

    - by user1756858
    I never did any vbscript before, so i don't know if my question is very easy one. Following is the flow of steps that has to be done : Check if exist and delete a folder at c:\test1 if found and continue. If not found continue. Check if exist and delete a folder at c:\programfiles\test2 if found and continue. If not found continue. Check if a desktop shortcut and start menu shortcut exist and delete if found. If not exit. I could delete 2 folders with the following code: strPath1 = "C:\test1" strPath1 = "C:\test1" DeleteFolder strPath1 DeleteFolder strPath1 Function DeleteFolder(strFolderPath1) Dim objFSO, objFolder Set objFSO = CreateObject ("Scripting.FileSystemObject") If objFSO.FolderExists(strFolderPath) Then objFSO.DeleteFolder strFolderPath, True End If Set objFSO = Nothing But i need to run one script to delete 2 folders in different paths, 2 shortcuts one in start menu and one on desktop. I was experimenting with this code to delete the shortcut on my desktop: Dim WSHShell, DesktopPath Set WSHShell = WScript.CreateObject("WScript.Shell") DesktopPath = WSHShell.SpecialFolders("Desktop") on error resume next Icon = DesktopPath & "\sample.txt" Set fs = CreateObject("Scripting.FileSystemObject") Set A = fs.GetFile(Icon) A.Delete WScript.Quit It works fine for txt file on desktop, but how do i delete a shortcut for an application from desktop as well as start menu.

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  • Applying drop shadows to divs

    - by CJD
    Hi everyone, I need a bit of help applying a drop shadow image to a range of DIV elements. The elements in question already have a background image so I am wrapping another DIV around them. Things get complicated further because I'm also using the 960gs CSS framework. This is my current HTML for a content box type display: <div class="grid_12 boxout-shadow-920"> <div class="boxout"> <p>planetCJD.co.uk is the personal site and blog of CJD. The site is still a work-in-progress but please do have a look around and let me know what you think! </p> </div> </div> Boxout CSS: .boxout { background:url("../images/overlay.png") repeat-x scroll 0 0 #EEEEEE; -moz-border-radius:4px 4px 4px 4px; border:1px solid #DDDDDD; margin-bottom:15px; padding:5px; } boxout-shadow-920 CSS: .boxout-shadow-920 { background:url("../images/box-shadow-920.png") no-repeat scroll 50% 101% transparent; } Now this works to a degree. The boxshadow image shows at the bottom of the content box which is what I would like. However as I'm using a fixed percentage of 101%, if the content box height is too small, not much of the drop shadow image gets shown, and if the content box is too big, whitespace starts to appear between the box and the shadow image. So anyway, what I'm looking for is a cross-browser CSS based solution for doing this properly. I'm sure there is an easy answer to this - any help is appreciated!

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  • Database source control with Oracle

    - by borjab
    I have been looking during hours for a way to check in a database into source control. My first idea was a program for calculating database diffs and ask all the developers to imlement their changes as new diff scripts. Now, I find that if I can dump a database into a file I cound check it in and use it as just antother type of file. The main conditions are: Works for Oracle 9R2 Human readable so we can use diff to see the diferences. (.dmp files doesn't seem readable) All tables in a batch. We have more than 200 tables. It stores BOTH STRUCTURE AND DATA It supports CLOB and RAW Types. It stores Procedures, Packages and its bodies, functions, tables, views, indexes, contraints, Secuences and synonims. It can be turned into an executable script to rebuild the database into a clean machine. Not limitated to really small databases (Supports least 200.000 rows) It is not easy. I have downloaded a lot of demos that does fail in one way or another. EDIT: I wouldn't mind alternatives aproaches provided that they allows us to check a working system against our release DATABASE STRUCTURE AND OBJECTS + DATA in a bath mode. By the way. Our project has been developed for years. Some aproaches can be easily implemented when you make a fresh start but seem hard at this point. EDIT: To understand better the problem let's say that some users can sometimes do changes to the config data in the production eviroment. Or developers might create a new field or alter a view without notice in the realease branch. I need to be aware of this changes or it will be complicated to merge the changes into production.

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  • Can anyone provide a good "idiot's guide" to creating an installer in VS2008 (C#) Pro?

    - by paxdiablo
    I have Visual C# 2008 Professional and have developed the first half of a C# application (console mode) with the second half in progress now (GUI). I'm looking for an easy path to creating an installer for it. What are the steps that need to be taken to produce a professional installer? There's a similar question here regarding the Express edition but I have Pro, and I would like as much as possible to stick with just the standard VS stuff (if you think you can convince me that a third party installer creator is much better than a VS-only solution, give it a shot, by all means). Keep in mind that I have no interest in upgrading to VS2010 yet, even if it's a hundred times easier to create an installer. That can come later, when the revenue starts rolling in :-) Also be aware that the GUI component of this application is a totally separate executable from the console part. The console part is a simple "open file 1, do some work on it, write file 2" type and the GUI is a fairly standard "open file, do some stuff" beast so there's no tricky or wildly undocumented behaviour happening. Basically, I'm looking for (at least) the following: professional looking installer. ability to specify where the application files go. changes to the registry to allow double-clicks on my file extension to open the GUI app with the file as an argument. needs to install everything required (my stuff, .Net if required, and so on).

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  • Change URL Submitted to Depending on Form Selection

    - by Chris
    I have a form which I need to submit to one of three different URLs depending on a selection made in the form. I suspect the easiest solution is to use jQuery to insert the appropriate path before the rest of the form parameters as the selection is made, but not sure on what the code would be. Any pointers greratly appreciated! <form id="myForm" action='/booking/default-path' accept-charset='utf-8' method='get'> <select name="paramA" id="paramA"> <option id="optionA" value="A" selected="selected">Option A</option> <option id="optionB" value="B">Option B</option> </select> <select name="currency" id="currency"> <option id="GBP" value="GBP" selected="selected">British Pounds</option> <option id="EUR" value="EUR">Euros</option> <option id="USD" value="USD">US Dollars</option> </select> <input type="submit" value="submit" id="submit" name="submit" /> </form> Where the three different URLs would be: ../booking/default-path-gbp?...[params here]... ../booking/default-path-eur?...[params here]... ../booking/default-path-usd?...[params here]... I know it would be a lot easier to incorporate the parameter in the usual way and just use one submission URL root, but unfortunately I'm submitting to an eComms system out of my control and am stuck with having to find a solution to this. Should be easy I think, but not sure where to start, jQuery used elsewhere, so would prefer to use this framework in any solutions.

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  • Is it theoretically possible to emulate a human brain on a computer?

    - by JoelK
    Our brain consists of billions of neurons which basically work with all the incoming data from our senses, handle our consciousness, emotions and creativity as well as our hormone system, etc. So I'm completely new to this topic but doesn't each neuron have a fixed function? E.g.: If a signal of strength x enters, if the last signal was x ms ago, redirect it. From what I've learned in biology about our nerves system which includes our brain because both consist of simple neurons, it seems to me as our brain is one big, complicated computer. Maybe so complicated that things such as intelligence and cognition become possible? As the most complicated things about a neuron pretty much are the chemical aspects on generating an electric singal, keeping itself alive, and eventually segmenting itself, it should be pretty easy emulating some on a computer, or? You won't have to worry about keeping your virtual neuron alive, or? If you can emulate a single neuron on a computer, which shouldn't be too hard, could you theoretically emulate more than 1000 billions of them, recreating intelligence, cognition and maybe even creativity? In my question I'm leaving out the following aspects: Speed of our current (super) computers Actually writing a program for emulating neurons I don't know much about this topic, please tell me if I got anything wrong :) (My secret goal: Make a copy of my brain and store it on some 10 million TB HDD and make someone start it up in the future)

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  • Have ASP page call save function anytime the user tries to navigate away from page

    - by Breander
    What I have is an input page with a bunch of dynamically created textboxes for the user to input data. The textboxes are dynamically created because the number that are needed are not known until the user selects some options on the page. So what I need to have happen is if the user tries to either A) navigate away from the page or B) select different options bringing up new textboxes. Anything the user may have typed into the textboxes needs to automatically be saved to the database. Like they clicked on the save button on the page. This doesn't sound like a vary smart way to do things or even an easy way to do things but this is the requirement I have been given. No message just save to the database. I have looked into things like onbeforepageunload javascript but that mostly tries to stop the user from navigating away I can't call any code behind code from it. Any help is appreciated. Note : The number of the texboxes with data can be any where between 20 and 500. Yes very crazy but not my idea.

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  • Spring Data Neo4J @Indexed(unique = true) not working

    - by Markus Lamm
    I'm new to Neo4J and I have, probably an easy question. There're NodeEntitys in my application, a property (name) is annotated with @Indexed(unique = true) to achieve the uniqueness like I do in JPA with @Column(unique = true). My problem is, that when I persist an entity with a name that already exists in my graph, it works fine anyway. But I expected some kind of exception here...?! Here' s an overview over basic my code: @NodeEntity public abstract class BaseEntity implements Identifiable { @GraphId private Long entityId; ... } public class Role extends BaseEntity { @Indexed(unique = true) private String name; ... } public interface RoleRepository extends GraphRepository<Role> { Role findByName(String name); } @Service public class RoleServiceImpl extends BaseEntityServiceImpl<Role> implements { private RoleRepository repository; @Override @Transactional public T save(final T entity) { return getRepository().save(entity); } } And this is my test: @Test public void testNameUniqueIndex() { final List<Role> roles = Lists.newLinkedList(service.findAll()); final String existingName = roles.get(0).getName(); Role newRole = new Role.Builder(existingName).build(); newRole = service.save(newRole); } That's the point where I expect something to go wrong! How can I ensure the uniqueness of a property, without checking it for myself?? THANKS IN ADVANCE FOR ANY IDEAS!! P.S.: I'm using neo4j 1.8.M07, spring-data-neo4j 2.1.0.BUILD-SNAPSHOT and Spring 3.1.2.RELEASE.

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  • Convert enumerated records to php object

    - by Matt H
    I have a table containing a bunch of records like this: +-----------+--------+----------+ | extension | fwd_to | type | +-----------+--------+----------+ | 800 | 11111 | noanswer | | 800 | 12345 | uncond | | 800 | 22222 | unavail | | 800 | 54321 | busy | | 801 | 123 | uncond | +-----------+--------+----------+ etc The query looks like this: select fwd_to, type from forwards where extension='800'; Now I get back an array containing objects which look like the following when printed with Kohana::debug: (object) stdClass Object ( [fwd_to] => 11111 [type] => noanswer ) (object) stdClass Object ( [fwd_to] => 12345 [type] => uncond ) (object) stdClass Object ( [fwd_to] => 22222 [type] => unavail ) (object) stdClass Object ( [fwd_to] => 54321 [type] => busy ) What I'd like to do is convert this to an object of this form: (object) stdClass Object ( [busy] => 54321 [uncond] => 12345 [unavail] => 22222 [noanswer] => 11111 ) The reason being I want to then call json_encode on it. This will allow me to use jquery populate to populate a form. Is there a suggested way I can do this nicely? I'm fairly new to PHP and I'm sure this is easy but it's eluding me at the moment.

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  • Web services or shared database for (game) server communication?

    - by jaaronfarr
    We have 2 server clusters: the first is made up of typical web applications backed by SQL databases. The second are highly optimized multiplayer game servers which keep all data in memory. Both clusters communicate with clients via HTTP (Ajax with JSON). There are a few cases in which we need to share data between the two server types, for example, reporting back and storing the results of a game (should ultimately end up in the database). We're considering several approaches for inter-server communication: Just share the MySQL databases between clusters (introduce SQL to the game servers) Sharing data in a distributed key-value store like Memcache, Redis, etc. Use an RPC technology like Google ProtoBufs or Apache Thrift Using RESTful web services (the game server would POST back to the web servers, for example) At the moment, we're leaning towards web services or just sharing the database. Sharing the database seems easy, but we're concerned this adds extra memory and a new dependency into the game servers. Web services provide good separation of concerns and fit with the existing Ajax we use, but add complexity, overhead and many more ways for communication to fail. Are there any other good reasons not to use one or the other approach? Which would be easier to scale?

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  • How can I avoid encoding mixups of strings in a C/C++ API?

    - by Frerich Raabe
    I'm working on implementing different APIs in C and C++ and wondered what techniques are available for avoiding that clients get the encoding wrong when receiving strings from the framework or passing them back. For instance, imagine a simple plugin API in C++ which customers can implement to influence translations. It might feature a function like this: const char *getTranslatedWord( const char *englishWord ); Now, let's say that I'd like to enforce that all strings are passed as UTF-8. Of course I'd document this requirement, but I'd like the compiler to enforce the right encoding, maybe by using dedicated types. For instance, something like this: class Word { public: static Word fromUtf8( const char *data ) { return Word( data ); } const char *toUtf8() { return m_data; } private: Word( const char *data ) : m_data( data ) { } const char *m_data; }; I could now use this specialized type in the API: Word getTranslatedWord( const Word &englishWord ); Unfortunately, it's easy to make this very inefficient. The Word class lacks proper copy constructors, assignment operators etc.. and I'd like to avoid unnecessary copying of data as much as possible. Also, I see the danger that Word gets extended with more and more utility functions (like length or fromLatin1 or substr etc.) and I'd rather not write Yet Another String Class. I just want a little container which avoids accidental encoding mixups. I wonder whether anybody else has some experience with this and can share some useful techniques. EDIT: In my particular case, the API is used on Windows and Linux using MSVC 6 - MSVC 10 on Windows and gcc 3 & 4 on Linux.

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  • Extra NotifyIcon shown in system tray

    - by Kettch19
    I'm having an issue with an app where my NotifyIcon displays an extra icon. The steps to reproduce it are easy, but the problem is that the extra icon shows up after any of the actual codebehind we've added fires. Put simply, clicking a button triggers execution of method FooBar() which runs all the way through fine but its primary duty is to fire a backgroundworker to log into another of our apps. It only appears if this particular button is clicked. Strangely enough, we have a WndProc method override and if I step through until the extra NotifyIcon appears, it always appears during this method so something else beyond the codebehind must be triggering the behavior. Our WndProc method is currently (although I don't think it's caused by the WndProc): Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message) 'Check for WM_COPYDATA message from other app or drag/drop action and handle message If m.Msg = NativeMethods.WM_COPYDATA Then ' get the standard message structure from lparam Dim CD As NativeMethods.COPYDATASTRUCT = m.GetLParam(GetType(NativeMethods.COPYDATASTRUCT)) 'setup byte array Dim B(CD.cbData) As Byte 'copy data from memory into array Runtime.InteropServices.Marshal.Copy(New IntPtr(CD.lpData), B, 0, CD.cbData) 'Get message as string and process ProcessWMCopyData(System.Text.Encoding.Default.GetString(B)) 'empty array Erase B 'set message result to 'true', meaning message handled m.Result = New IntPtr(1) End If 'pass on result and all messages not handled by this app MyBase.WndProc(m) End Sub The only place in the code where the NotifyIcon in question is manipulated at all is in the following event handler (again, don't think this is the culprit, but just for more info): Private Sub TrayIcon_MouseDoubleClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles TrayIcon.MouseDoubleClick If Me.Visible Then Me.Hide() Else PositionBottomRight() Me.Show() End If End Sub The backgroundworker's DoWork is as follows (just a class call to log in to our other app, but again just for info): Private Sub LoginBackgroundWorker_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles LoginBackgroundWorker.DoWork Settings.IsLoggedIn = _wdService.LogOn(Settings.UserName, Settings.Password) End Sub Does anyone else have ideas on what might be causing this or how to possibly further debug this? I've been banging my head on this without seeing a pattern so another set of eyes would be extremely appreciated. :) I've posted this on MSDN winforms forums as well and have had no luck there so far either.

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  • Grails - Where to store properties related to domains

    - by GalmWing
    This is something I have been struggling about for some time now. The thing is: I have many (20 or so) static arrays of values. I say static because that is how I'm actually storing them, as static arrays inside some domains. For example, if I have a list of known websites, I do: class Website { ... static websites = ["web1", "web2" ...] } But I do this just while developing, because I can easily change the arrays if needed, but what I'm going to do when the application is ready for deployment? In my project it is very probable that, at some point, these arrays of values change. I've been researching on that matter, one can store application properties inside an external .properties file, but it will be impossible to store an array, even futile, because if some array gets an additional value, the application can't recognize it until the name of the new property is added where needed. Another approach is to store this information in the database, but for some reason it seems like a waste to add 20 or more tables that will have just two rows, an id and a name. And the last option, as far as I know, would be an XML, but I'm not very experienced with those. It seems groovy has a way of creating and reading XML files relatively easy, but I don't know how difficult would be to modify an XML whose layout is predefined in the application. Needless to say that storing them in the config.groovy is not an option since any change will require to recompile. I haven't come across some "standard" (maybe a best practice?) way of dealing with these. So the questions is: Where to store these arrays?

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  • c++ and visual studio 08, how to develop the following web extracting application. folloow up of las

    - by user287745
    the purpose is to use c++ in a useful way. i have just started programming and have made a few small applications in c and c#. my understanding is that programming for web and thing related to web is now a days a very easy task. please note this is for personnel learning not for rent a coder or any money making. an application which can run on any windows platform even win98. the application should start automatically at a scheduled time and do the following. connect to a site which displays stock prices summary (high low current open ). captures the data (excluding the other things in the site) and saves it to disk ( a sql database) please note:- internet connection is assumed to be there always. do not want to know how to make database schema or database. the stock exchange has no law prohibiting the use of the data provided on its site, but i do not want to mention the name in case i am wrong, but its for personnel private use only. the data of summary of pricing is arranged in a table such that when copied pasted to ms excel it automatically forms a table. guidance needed thank u.

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