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  • Creating a new object destroys an older object with different name in C++

    - by Mikael
    First question here! So, I am having some problems with pointers in Visual C++ 2008. I'm writing a program which will control six cameras and do some processing on them so to clean things up I have created a Camera Manager class. This class handles all operations which will be carried out on all the cameras. Below this is a Camera class which interacts with each individual camera driver and does some basic image processing. Now, the idea is that when the manager is initialised it creates two cameras and adds them to a vector so that I can access them later. The catch here is that when I create the second camera (camera2) the first camera's destructor is called for some reason, which then disconnects the camera. Normally I'd assume that the problem is somewhere in the Camera class, but in this case everything works perfectly as long as I don't create the camera2 object. What's gone wrong? CameraManager.h: #include "stdafx.h" #include <vector> #include "Camera.h" class CameraManager{ std::vector<Camera> cameras; public: CameraManager(); ~CameraManager(); void CaptureAll(); void ShowAll(); }; CameraManager.cpp: #include "stdafx.h" #include "CameraManager.h" CameraManager::CameraManager() { printf("Camera Manager: Initializing\n"); [...] Camera *camera1 = new Camera(NodeInfo,1, -44,0,0); cameras.push_back(*camera1); // Adding the following two lines causes camera1's destructor to be called. Why? Camera *camera2 = new Camera(NodeInfo,0, 44,0,0); cameras.push_back(*camera2); printf("Camera Manager: Ready\n"); }

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  • Is this overly clever or unsafe?

    - by Liberalkid
    I was working on some code recently and decided to work on my operator overloading in c++, because I've never really implemented it before. So I overloaded the comparison operators for my matrix class using a compare function that returned 0 if LHS was less than RHS, 1 if LHS was greater than RHS and 2 if they were equal. Then I exploited the properties of logical not in c++ on integers, to get all of my compares in one line: inline bool Matrix::operator<(Matrix &RHS){ return ! (compare(*this,RHS)); } inline bool Matrix::operator>(Matrix &RHS){ return ! (compare((*this),RHS)-1); } inline bool Matrix::operator>=(Matrix &RHS){ return compare((*this),RHS); } inline bool Matrix::operator<=(Matrix &RHS){ return compare((*this),RHS)-1; } inline bool Matrix::operator!=(Matrix &RHS){ return compare((*this),RHS)-2; } inline bool Matrix::operator==(Matrix &RHS){ return !(compare((*this),RHS)-2); } Obviously I should be passing RHS as a const, I'm just probably not going to use this matrix class again and I didn't feel like writing another function that wasn't a reference to get the array index values solely for the comparator operation.

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  • Using Java classes(whole module with Spring/Hibernate dependency) in Grails

    - by Sitaram
    I have a Java/Spring/Hibernate application with a payment module. Payment module has some domain classes for payment subscription and transactions etc. Corresponding hibernate mapping files are there. This module uses applicationContext.xml for some of the configuration it needs. Also, This module has a PaymentService which uses a paymentDAO to do all database related work. Now, I want to use this module as it is(without any or minimal re-writing) in my other application(Grails application). I want to bring in the payment module as a jar or copy the source files to src/java folder in Grails. With that background, I have following queries: Will the existing applicationContext.xml for Spring configuration in the module will work as it is in Grails? Does it merge with rest of Grails's Spring config? Where do I put the applicationContext.xml? classpath? src/java should work? Can I bundle the applicationContext.xml in Jar(If I use jar option) and can overwrite in Grails if anything needs to be changed? Multiple bean definition problems in that case? PaymentService recognized as regular service? Will it be auto-injected in controllers and/or other services? Will PaymentDAO use the datasource configuration of Grails? Where do I put the hbm files of this module? Can I bundle the hbm files in Jar(If I use jar option) and can overwrite in Grails if anything needs to be changed? Which hbms are picked? or, there will be problems with that? Too many questions! :) All these concerns are actually before trying. I am going to try this in next few days(busy currently). Any help is appreciated. Thanks. Sitaram Meena

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  • perl multithreading issue for autoincrement

    - by user3446683
    I'm writing a multi threaded perl script and storing the output in a csv file. I'm trying to insert a field called sl.no. in the csv file for each row entered but as I'm using threads, the sl. no. overlaps in most. Below is an idea of my code snippet. for ( my $count = 1 ; $count <= 10 ; $count++ ) { my $t = threads->new( \&sub1, $count ); push( @threads, $t ); } foreach (@threads) { my $num = $_->join; } sub sub1 { my $num = shift; my $start = '...'; #distributing data based on an internal logic my $end = '...'; #distributing data based on an internal logic my $next; for ( my $x = $start ; $x <= $end ; $x++ ) { my $count = $x + 1; #part of code from which I get @data which has name and age my $j = 0; if ( $x != 0 ) { $count = $next; } foreach (@data) { #j is required here for some extra code flock( OUTPUT, LOCK_EX ); print OUTPUT $count . "," . $name . "," . $age . "\n"; flock( OUTPUT, LOCK_UN ); $j++; $count++; } $next = $count; } return $num; } I need the count to be incremented which is the serial number for the rows that would be inserted in the csv file. Any help would be appreciated.

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  • Cross-browser method for getting width and height of a DIV?

    - by thinkthank
    This is my first post, so please go easy on me. I'm sure I'm doing everything wrong. However, I couldn't find any posts that answered the question above. I use jQuery. I'm trying to find a way to get the current width and height of a DIV element, even if they're set to "auto". I've found many ways to do this, but no method returns the same width in IE. It is important that this method is cross-browser, as it will break the layout of the page if different numbers are returned in different browsers. .width() and .height() do not work because in IE, padding is subtracted (e.g. width() returns 25 where width is 30 and padding is 5). .outerWidth() and .outerHeight() are not consistent either. While they work IE (believe it or not) in FF, the padding is added again to the full width (e.g. outerWidth() returns 110 in FF where width is 100px and padding is 10px). Is there any way out of this mess without writing complex browser checks? Thanks!

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  • Breaking dependencies when you can't make changes to other files?

    - by codemuncher
    I'm doing some stealth agile development on a project. The lead programmer sees unit testing, refactoring, etc as a waste of resources and there is no way to convince him otherwise. His philosophy is "If it ain't broke don't fix it" and I understand his point of view. He's been working on the project for over a decade and knows the code inside and out. I'm not looking to debate development practices. I'm new to the project and I've been tasked with adding a new feature. I've worked on legacy projects before and used agile development practices with good result but those teams were more receptive to the idea and weren't afraid of making changes to code. I've been told I can use whatever development methodology I want but I have to limit my changes to only those necessary to add the feature. I'm using tdd for the new classes I'm writing but I keep running into road blocks caused by the liberal use of global variables and the high coupling in the classes I need to interact with. Normally I'd start extracting interfaces for these classes and make their dependence on the global variables explicit by injecting them as constructor arguments or public properties. I could argue that the changes are necessary but considering the lead never had to make them I doubt he would see it my way. What techniques can I use to break these dependencies without ruffling the lead developer's feathers? I've made some headway using: Extract Interface (for the new classes I'm creating) Extend and override the wayward classes with test stubs. (luckily most methods are public virtual) But these two can only get me so far.

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  • (illustrator scripting) how to release objects to layers(sequence) but retain object's name?

    - by Eugene
    Hi, I've asked the same question to adobe scripting forum. but seems there are not many forum users there, and I'm asking the same question here. I was writing my first illustrator script to export all layers to png files with layer structure converted to file structure. I found there are many layers that my script can't detect and found out that they are not actually layers but objects(or groups). Found a layer menu (release to layers), but doesn't quite solve the problem perfectly. initially I have this layer 001 object 01 object 1 object 2 release to layers(sequence) on object 01 gives layer 001 layer 91(whatever the layer number illustrator gives when release to layers are performed) layer 92 object 1 layer 93 object 2 now I need to convert them to (so that layer can retain the name of the object) layer 001 layer 01 layer 1 object 1 layer 2 object 2 I have hundreds of layer 001, and couple thousands of object 01, and wonder if anything can be done with script to do this... If it's possible to detect object in a script, I could rewrite the 'release to layers' functionality in script maybe. Any help would be greatly appreciated.

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  • Reading from an write-only(OUT) parameter in pl/sql

    - by sqlgrasshopper5
    When I tried writing to an read-only parameter(IN) of a function, Oracle complains with an error. But that is not the case when reading from an write-only(OUT) parameter of a function. Oracle silently allows this without any error. What is the reason for this behaviour?. The following code executes without any assignment happening to "so" variable: create or replace function foo(a OUT number) return number is so number; begin so := a; --no assignment happens here a := 42; dbms_output.put_line('HiYA there'); dbms_output.put_line('VAlue:' || so); return 5; end; / declare somevar number; a number := 6; begin dbms_output.put_line('Before a:'|| a); somevar := foo(a); dbms_output.put_line('After a:' || a); end; / Here's the output I got: Before a:6 HiYA there VAlue: After a:42

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  • Use of unassigned local variable 'xxx'

    - by Tomislav
    I'm writing a database importer from our competitors to ours database:) I have a code generator which create Methods form import to our database like public void Test_Import_Customer_1() // variables string conn; string sqlSelect; string sqlInsert; int extID; string name; string name2; DateTime date_inserted; sqlSelect="select id,name,date_inserted from table_competitors_1"; oledbreader reader = new GetOledbRader(sqlString,conn); while (reader.read()) { name=left((string)myreader["name"],50); //limitation of my field date_inserted=myreader["date_inserted"]; sqlInsert=string.Format("insert into table(name,name2,date_inserted)values '{0}', '{1}', {2})",name,name2,date_inserted); //here is the problem name2 "Use of unassigned local variable" ExecuteSQL(sqlInsert) } As different companies database has different fields i can not set value to each variable and there is a big number of tables to go one variable to next. like sqlSelect_Company_1 = "select name,date_inserted from table_1"; sqlSelect_Company_2 = "select name,name2 from table_2"; is there a way to override the typing of each variable one by one with default values?

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  • extra new lines with several outputStream.write

    - by Sam
    Hi All, I am writing jsp to export data in excel format to user. An excel could be recieved on the cient side. However, since there's large amount of data, and I don't want to keep it in the server memory and write them at the end. I try to divide them and write serveral times. However, each extra write(..) will cause an extra new lines at the top of the excel worksheet and then the extra data is placed after these new lines. Does anyone know the reasons? The code is something like this: response.setHeader("Content-disposition","attachment;filename=DocuShareSearch.xls"); response.setHeader("Content-Type", "application/octet-stream"); responseContent ="<table><tr><td>12131</td></tr>......."; byte[] responseByte1 = responseContent.getBytes("utf-16"); outputStream.write(responseByte1, 0, responseByte1.length ); responseContent =".....<tr><td>12131</td></tr></table>"; byte[] responseByte2 = responseContent.getBytes("utf-16"); outputStream.write(responseByte2, 0, responseByte2.length ); outputStream.close();

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  • #include - brackets vs quotes in XCode?

    - by Chris Becke
    In MSVC++ #include files are searched for differently depending on whether the file is enclosed in "" or <. The quoted form searches first in the local folder, then in /I specified locations, The angle bracket form avoids the local folder. This means, in MSVC++, its possible to have header files with the same name as runtime and SDK headers. So, for example, I need to wrap up the windows sdk windows.h file to undefine some macro's that cause trouble. With MSVS I can just add a (optional) windows.h file to my project as long as I include it using the quoted form :- // some .cpp file #include "windows.h" // will include my local windows.h file And in my windows.h, I can pull in the real one using the angle bracket form: // my windows.h #include <windows.h> // will load the real one #undef ConflictingSymbol Trying this trick with GCC in XCode didn't work. angle bracket #includes in system header files in fact are finding my header files with similar names in my local folder structure. The MSVC system means its quite safe to have a "String.h" header file in my own folder structre. On XCode this seems to be a major no no. Is there some way to control this search path behaviour in XCode to be more like MSVC's? Or do I just have to avoid naming any of my headers anything that might possibly conflict with a system header. Writing cross platform code and using lots of frameworks means the possibility of incidental conflicts seems large.

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  • Tool to migrate a repo with only read access?

    - by Corazu
    I have a subversion repository located on our school servers from a project my friends and I worked on the past semester. We want to take the project and polish it and make it more of a portfolio item and I'm not quite sure that the repo will stay intact on the school servers (they usually wipe it after a few semesters). I don't have access to dump the repo, although I've sent an email to see if I can get one - which would be the best solution. I tried svnsync but the school server doesn't support the replay command (probably turned off), so that won't work for me. Now, theoretically, wouldn't it be possible to (manually or programmatically) checkout each revision of the repository and check it in to a new repository on our own server? I think it would work - there's only 3 of us, and there's no working copy conflicts that we'd have to worry about, just want a copy of all the history in the repo in case we need to go back and look at it. That being said, before I go and reinvent a wheel by writing a script to do it - does something like this already exist? I have to figure there's already a tool to do it, or that someone has wrote a script to do it.

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  • System Error when running PyQt4's loadUi()

    - by user633804
    Hello, I'm pretty new to Qt, Python and their combinations. I'm currently writing a QGIS plugin in python (I used QtCreator 2.1 (Qt Designer 4.7) to generate a .ui-file and am now trying to use it for a Quantum GIS plugin that's written in Python 2.5 (and running in the Quantum GIS Python 2.5 console)). I am running into trouble when loading the ui-file dynamically when the program runs the loadUi() function. What throws me off is that the error occurs outside my script. Does that mean, I'm passing something wrong into it? Where does the error come in? Any hints on what could be wrong? code_dir = os.path.dirname(os.path.abspath(__file__)) self.ui = loadUi(os.path.join(code_dir, "Ui_myfile.ui"), self) This is the Error Code I am getting (minus the first paragraph): File "C:/Dokumente und Einstellungen/name.name/.qgis/python/plugins\myfile\myfile_gui.py", line 42, in __ init __ self.ui = loadUi(os.path.join(code_dir, "Ui_myfile.ui"), self) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic__init__.py", line 112, in loadUi return DynamicUILoader().loadUi(uifile, baseinstance) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\Loader\loader.py", line 21, in loadUi return self.parse(filename) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 768, in parse actor(elem) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 616, in createUserInterface self.traverseWidgetTree(elem) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 594, in traverseWidgetTree handler(self, child) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 233, in createWidget topwidget.setCentralWidget(widget) SystemError: error return without exception set

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  • String comparison in Python: is vs. ==

    - by Coquelicot
    I noticed a Python script I was writing was acting squirrelly, and traced it to an infinite loop, where the loop condition was "while line is not ''". Running through it in the debugger, it turned out that line was in fact ''. When I changed it to != rather than 'is not', it worked fine. I did some searching, and found this question, the top answer to which seemed to be just what I needed. Except the answer it gave was counter to my experience. Specifically, the answerer wrote: For all built-in Python objects (like strings, lists, dicts, functions, etc.), if x is y, then x==y is also True. I double-checked the type of the variable, and it was in fact of type str (not unicode or something). Is his answer just wrong, or is there something else afoot? Also, is it generally considered better to just use '==' by default, even when comparing int or Boolean values? I've always liked to use 'is' because I find it more aesthetically pleasing and pythonic (which is how I fell into this trap...), but I wonder if it's intended to just be reserved for when you care about finding two objects with the same id.

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  • Autoscale Font in a TextBox Control so that its as big as possible and still fits in text area bound

    - by blak3r
    I need a TextBox or some type of Multi-Line Label control which will automatically adjust the font-size to make it as large as possible and yet have the entire message fit inside the bounds of the text area. I wanted to see if anyone had implemented a user control like this before developing my own. Example application: have a TextBox which will be half of the area on a windows form. When a message comes in which is will be approximately 100-500 characters it will put all the text in the control and set the font as large as possible. An implementation which uses Mono Supported .NET libraries would be a plus. Thanks in advance. If know one has implemented a control already... If someone knows how to test if a given text completely fits inside the text area that would be useful for if I roll my own control. Edit: I ended up writing an extension to RichTextBox. I will post my code shortly once i've verified that all the kinks are worked out.

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  • How to debug memory allocation issues?

    - by amitabh
    Hi I am writing an iPhone app that that is trying to create a second a view when the user clicks on an element in UITableView. The code looks like ReplyToViewController *reply = [[ReplyToViewController alloc] initWithNibName:@"ReplyTo" bundle:nil]; reply.delegate = self; Message *message = [resultData objectAtIndex:indexPath.row]; int dbid = [message.bizid intValue]; NSLog(@"dbid=%d",dbid); reply.currentMessage = message; reply.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal; [self presentModalViewController:reply animated:YES]; The reply object gets created properly and the view is proper. Last line in above code segment calls some framework code which eventually calls the viewDidLoad method of the ReplyToViewController. Address of the reply object in the above code and the address of the object in viewDidLoad is not same. Any idea where this new object is coming from? How do I debug? I also added init method the following method in ReplyToViewController hoping that it will get called and I can find who is creating this new object. But it does not stop in this method. Any help will be greatly appreciated. - (id) init { /* first initialize the base class */ self = [super init]; return self; } // Following gets called from the 1st code segment. - (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil { if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) { // Custom initialization } return self; } - (void)viewDidLoad { [super viewDidLoad]; NSLog(currentMessage.text]; // THIS returns nil and the program fails later in the code. }

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  • Unpacking varargin to individual variables

    - by Richie Cotton
    I'm writing a wrapper to a function that takes varargin as its inputs. I want to preserve the function signature in the wrapper, but nesting varargin causes all the variable to be lumped together. function inner(varargin) %#ok<VANUS> % An existing function disp(nargin) end function outer(varargin) % My wrapper inner(varargin); end outer('foo', 1:3, {}) % Uh-oh, this is 1 I need a way to unpack varargin in the outer function, so that I have a list of individual variables. There is a really nasty way to do this by constructing a string of the names of the variables to pass the inner, and calling eval. function outer2(varargin) %#ok<VANUS> % My wrapper, second attempt inputstr = ''; for i = 1:nargin inputstr = [inputstr 'varargin{' num2str(i) '}']; %#ok<AGROW> if i < nargin inputstr = [inputstr ', ']; %#ok<AGROW> end end eval(['inner(' inputstr ')']); end outer2('foo', 1:3, {}) % 3, as it should be Can anyone think of a less hideous way of doing things, please?

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  • Ways to implement tags - pros and cons of each

    - by bobobobo
    Related Using SO as an example, what is the most sensible way to manage tags if you anticipate they will change often? Way 1: Seriously denormalized (comma delimited) table posts +--------+-----------------+ | postId | tags | +--------+-----------------+ | 1 | c++,search,code | Here tags are comma delimited. Pros: Tags are retrieved at once with a single select query. Updating tags is simple. Easy and cheap to update. Cons: Extra parsing on tag retrieval, difficult to count how many posts use which tags. (alternatively, if limited to something like 5 tags) table posts +--------+-------+-------+-------+-------+-------+ | postId | tag_1 | tag_2 | tag_3 | tag_4 | tag_5 | +--------+-------+-------+-------+-------+-------+ | 1 | c++ |search | code | | | Way 2: "Slightly normalized" (separate table, no intersection) table posts +--------+-------------------+ | postId | title | +--------+-------------------+ | 1 | How do u tag? | table taggings +--------+---------+ | postId | tagName | +--------+---------+ | 1 | C++ | | 1 | search | Pros: Easy to see tag counts (count(*) from taggings where tagName='C++'). Cons: tagName will likely be repeated many, many times. Way 3: The cool kid's (normalized with intersection table) table posts +--------+---------------------------------------+ | postId | title | +--------+---------------------------------------+ | 1 | Why is a raven like a writing desk? | table tags +--------+---------+ | tagId | tagName | +--------+---------+ | 1 | C++ | | 2 | search | | 3 | foofle | table taggings +--------+---------+ | postId | tagId | +--------+---------+ | 1 | 1 | | 1 | 2 | | 1 | 3 | Pros: No repeating tag names. More girls will like you. Cons: More expensive to change tags than way #1.

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  • Delphi: Transporting Objects to remote computers

    - by pr0wl
    Hallo. I am writing a tier2 ordering software for network usage. So we have client and server. On the client I create Objects of TBest in which the Product ID, the amount and the user who orders it are saved. (So this is a item of an Order). An order can have multiple items and those are saved in an array to later send the created order to the server. The class that holds the array is called TBestellung. So i created both TBest.toString: string; and TBest.fromString(source: string): TBest; Now, I send the toString result to the server via socket and on the server I create the object using fromString (its parsing the attributes received). This works as intended. Question: Is there a better and more elegant way to do that? Serialisation is a keyword, yes, but isn't that awful / difficult when you serialize an object (TBestellung in this case) that contains an Array of other Objects (TBest in this case)? //Small amendment: Before it gets asked. Yes I should create an extra (static) class for toString and fromString because otherwise the server needs to create an "empty" TBest in order to be able to use fromString.

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  • Should a developer write their own test plan for Q/A?

    - by Mat Nadrofsky
    Who writes the test plans in your shop? Who should write them? I realize developers (like me) regularly do their own unit testing whilst developing and in some cases even their own Q/A depending on the size of the shop and the nature of the business, but in a big software shop with a full development team and Q/A team, who should be writing those official "my changes are done now" test plans? Soon, we'll be bringing on another Q/A member to our development team. My question is, going forward, is it a good practice to get your developers to write their own test plans? Something tells me that part of that might make sense but another part might not... What I like about that: Developer is very familiar with the changes made, thus it's easy to produce a document... What I don't like about that: Developer knows how it's supposed to work and might write a test plan that caters to this without knowing it. So, with the above in mind, what is the general stance on this topic? I'm of course already reading books like the Mythical Man-Month, Code Complete and a few others which really do help, but I'd like to get some input from the group as well.

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  • How to make ActiveRecord work with legacy partitioned/sharded databases/tables?

    - by Utensil
    thanks for your time first...after all the searching on google, github and here, and got more confused about the big words(partition/shard/fedorate),I figure that I have to describe the specific problem I met and ask around. My company's databases deals with massive users and orders, so we split databases and tables in various ways, some are described below: way database and table name shard by (maybe it's should be called partitioned by?) YZ.X db_YZ.tb_X order serial number last three digits YYYYMMDD. db_YYYYMMDD.tb date YYYYMM.DD db_YYYYMM.tb_ DD date too The basic concept is that databases and tables are seperated acording to a field(not nessissarily the primary key), and there are too many databases and too many tables, so that writing or magically generate one database.yml config for each database and one model for each table isn't possible or at least not the best solution. I looked into drnic's magic solutions, and datafabric, and even the source code of active record, maybe I could use ERB to generate database.yml and do database connection in around filter, and maybe I could use named_scope to dynamically decide the table name for find, but update/create opertions are bounded to "self.class.quoted_table_name" so that I couldn't easily get my problem solved. And even I could generate one model for each table, because its amount is up to 30 most. But this is just not DRY! What I need is a clean solution like the following DSL: class Order < ActiveRecord::Base shard_by :order_serialno do |key| [get_db_config_by(key), #because some or all of the databaes might share the same machine in a regular way or can be configed by a hash of regex, and it can also be a const get_db_name_by(key), get_tb_name_by(key), ] end end Can anybody enlight me? Any help would be greatly appreciated~~~~

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  • How to write an R function that evaluates an expression within a data-frame

    - by Prasad Chalasani
    Puzzle for the R cognoscenti: Say we have a data-frame: df <- data.frame( a = 1:5, b = 1:5 ) I know we can do things like with(df, a) to get a vector of results. But how do I write a function that takes an expression (such as a or a > 3) and does the same thing inside. I.e. I want to write a function fn that takes a data-frame and an expression as arguments and returns the result of evaluating the expression "within" the data-frame as an environment. Never mind that this sounds contrived (I could just use with as above), but this is just a simplified version of a more complex function I am writing. I tried several variants ( using eval, with, envir, substitute, local, etc) but none of them work. For example if I define fn like so: fn <- function(dat, expr) { eval(expr, envir = dat) } I get this error: > fn( df, a ) Error in eval(expr, envir = dat) : object 'a' not found Clearly I am missing something subtle about environments and evaluation. Is there a way to define such a function?

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  • Codeigniter only loads the default controller

    - by fh47331
    I am very new to CodeIgniter, but have been programming PHP for ages. I'm writing some software at the moment and using CI for the first time with it. The default controller is set to the first controller I want to action call 'login' (the controller is login.php, the view is login.php. When the form is submitted it calls the 'authenticate' controller. This executes fine, process the login data correctly and then does a redirect command (without any output to the screen prior) to the next page in this case 'newspage'. The problem is that the redirect, never reaches 'newspage' but the default controller runs again. It doesn't matter what I put ... ht tp://domain.name/anything ... (yes im using .htaccess to remove the index.php) the anything never gets called, just the default controller. I have left the standard 'welcome.php' controller and 'welcome_message.php' in the folders and even putting ht tp://domain.name/welcome all I get is the login screen! (Obviously there shouldn't be a space between the http - thats just done so it does not show as a hyperlink!) Can anyone tell me what i've done wrong!

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  • Calculating distance between two X,Y coordinates

    - by Umopepisdn
    I am writing a tool for a game that involves calculating the distance between two coordinates on a spherical plane 500 units across. That is, [0,0] through [499,499] are valid coordinates, and [0,0] and [499,499] are also right next to each other. Currently, in my application, I am comparing the distance between a city with an [X,Y] location respective to the user's own [X,Y] location, which they have configured in advance. To do this, I found this algorithm, which kind of works: Math.sqrt ( dx * dx + dy * dy ); Because sorting a paged list by distance is a useful thing to be able to do, I implemented this algorithm in a MySQL query and have made it available to my application using the following part of my SELECT statement: SQRT( POW( ( ".strval($sourceX)." - cityX ) , 2 ) + POW( ( ".strval($sourceY)." - cityY ) , 2 ) ) AS distance This works fine for many calculations, but does not take into account the fact that [0,0] and [499,499] are kitty-corner to one another. Is there any way I can tweak this algorithm to generate an accurate distance, given that 0 and 499 are adjacent? Thanks, -Umo

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  • iPhone inputting NSUserDefaults into a UITextField

    - by Rob
    I am writing a program where I where the first time a user runs it - they will have to fill out about 10 different UITextFields. I am trying to save the fields so that on subsequent runs of the program that whatever they previously put will already be displayed in those UITextFields so the wont have to re-input it in - unless they want to edit something in which case they still have that option. I think that I have figured out a good way to save the strings using NSUserDefaults but now I am trying to figure out how to have those fields populate a UITextField - it doesnt seem as easy as if they were UILabels. This is the route I am attempting: // in the viewDidLoad portion. NSUserDefaults *userData = [NSUserDefaults standardUserDefaults]; //Hooks. NSString *placeHolderName = [userData stringForKey:@"name"]; txtName.text = @"%@", placeHolderName; When I do this, it simply displays the '%@' in the textfields. I want whatever variable being held by placeHolderName to be automatically put into that UITextField. Is this possible?

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