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• Safari Web Inspector is not updating when I update an element with ajax

  - by Ashley

  I have a checkout page http://www.oipolloi.com/oipolloi/shop/viewbasket.php with multiple ajax calls after certain items update (EG look up postage cost when country is changed, then update discount boxes etc). I've asked for help in the past about the best method of making sure ALL calls have returned before allowing the form to be submitted for payment processing: http://stackoverflow.com/questions/2290372/how-do-i-prevent-form-submission-until-multiple-ajax-calls-have-finished-jquery I was fairly happy that the logic in the finished solution was correct, but I have still been receiving reports that people using Safari are able to submit the form without the ajax calls returning properly. I have tried using the Safari Web Inspector to debug but it seems that when you Inspect Element, then update an element with an ajax call, the Inspector doesn't seem to update. I am updating hidden fields, so it's hard to be able to know whether the problem lies with the DOM not being updated properly, or the Inspector itself. I'm using Safari 4.0.5 on PC and you can reproduce the problem above by looking for a div id="countryFieldsBilling" with Web Inspector. It should contain three hidden fields that are initially empty. You can try to make it update (or not) by choosing a country from the select menu at the bottom of 'Shipping Address' box, and then clicking the 'click to use Shipping Address' link at the top of the 'Billing Address' just below. The behaviour I am seeing is that the country chosen in the shipping select gets copied correctly to the country in the billing select, but the hidden inputs in the Web Inspector do not get updated. When these hidden inputs do not get updated, this causes the problem that Mac Safari users report. If you can let me know either how to get Web Inspector to work properly, or something else I may have missed in the behaviour of Mac Safari that may cause these problems, that would be great. Thanks in advance

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• Django - Moving database from development to production servers

  - by Garfonzo

  I am working on a Django project with a MySQL backend. I'm curious about the best way to update a production server's database to reflect the changes made on the development server's database? When I develop now, I make some changes to a models.py file, then to a schemamigration using South. Sometimes I do several migrations across several apps within the main project folder before it's ready for the production database. This means that there are several migration files in the app/migrations/ folder created by South. So on the production server, how does one update the database to reflect all the changes made in development, without having any data loss?

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• Jetty 7 will not allow me to customize a session cookie path

  - by Bob Obringer

  Using Jetty 7.0.2, I am unable to set a custom session cookie path. I am hosting multiple sites on the same server using apache to proxy requests to the proper context. (replaced http as htp as stackoverflow thinks my multiple links might be spam) <VirtualHost *:80> ServerName context.domain.com ProxyRequests On ProxyPreserveHost Off <Proxy *:80> Order deny,allow Allow from 127.0.0.1 </Proxy> ProxyPass / htp://localhost:8080/context/ ProxyPassReverse / htp://localhost:8080/context/ <Location /> Order allow,deny Allow from all </Location> </VirtualHost> Jetty is running on the same server on port 8080 and my context is available @ /context The user accesses the application @ htp://context.domain.com but jetty is setting the path for the session cookie @ /context. This prevents the browser from accessing the cookie since the the actual path to the context is not being used. I need to override Jetty's default setting to set the cookie for the context, and set the path at the root ( / ). In my Jetty's webdefault.xml I have the following, which is partially working: <context-param> <param-name>org.eclipse.jetty.servlet.SessionCookie</param-name> <param-value>CustomCookieName</param-value> </context-param> <context-param> <param-name>org.eclipse.jetty.servlet.SessionPath</param-name> <param-value>/</param-value> </context-param> The cookie is properly set with a custom name, but it is NOT setting the SessionPath. No matter what I set the value to... it refuses to set a cookie at any path but /context. This has been driving me crazy so any help would be greatly appreciated.

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• Dependency injection in constructors

  - by andre

  Hello everyone. I'm starting a new project and setting up the base to work on. A few questions have risen and I'll probably be asking quite a few in here, hopefully I'll find some answers. First step is to handle dependencies for objects. I've decided to go with the dependency injection design pattern, to which I'm somewhat new, to handle all of this for the application. When actually coding it I came across a problem. If a class has multiple dependencies and you want to pass on multiple dependencies via the constructor (so that they cannot be changed after you instantiate the object). How do you do it without passing an array of dependencies, using call_user_func_array(), eval() or Reflection? This is what i'm looking for: <?php class DI { public function getClass($classname) { if(!$this->pool[$classname]) { # Load dependencies $deps = $this->loadDependencies($classname); # Here is where the magic should happen $instance = new $classname($dep1, $dep2, $dep3); # Add to pool $this->pool[$classname] = $instance; return $instance; } else { return $this->pool[$classname]; } } } Again, I would like to avoid the most costly methods to call the class. Any other suggestions?

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• Entity Framework and WCf

  - by Nihilist

  Hi I am little confused on designing WCf services with EF. When using WCf and EF, where do we draw this line on what properties to return and what not to with the entity. Here is my scenario I have User. Here are the relations. User [1 to many] Address, User [ 1 to many] Email, User [ 1 to many] Phone So now on the webform, on page1 I can edit user information. say I can edit few properties on the user entity and can also edit address, phone, email entities[ like add / delete and update any] On page2, i can only update user properties and nothing related to navigation properties [ address, email, phone]. So when I return the User Entity [ OR DTO] should i be returning the navigation properties too? Or should the client make multiple calls to get navigation properites. Also, how does it go with Save? Like should the client make multiple calls to save user and related entites or just one call to save the graph? Lets say, if I just have a Save(User user) [ where user has all the related entities too] both page1 and page2 will call save and pass me the user. but one page1 i will need a lot more information. but on page2 i just need the user primitive properties. So my question is, where do we draw this line, how do we design theses services ? Is the WCF operation designed on the page and the fields it has ? I am hoping i explained my problem well enough.

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• Sharing a COM port over TCP

  - by guinness

  What would be a simple design pattern for sharing a COM port over TCP to multiple clients? For example, a local GPS device that could transmit co-ordinates to remote hosts in realtime. So I need a program that would open the serial port and accept multiple TCP connections like: class Program { public static void Main(string[] args) { SerialPort sp = new SerialPort("COM4", 19200, Parity.None, 8, StopBits.One); Socket srv = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); srv.Bind(new IPEndPoint(IPAddress.Any, 8000)); srv.Listen(20); while (true) { Socket soc = srv.Accept(); new Connection(soc); } } } I would then need a class to handle the communication between connected clients, allowing them all to see the data and keeping it synchronized so client commands are received in sequence: class Connection { static object lck = new object(); static List<Connection> cons = new List<Connection>(); public Socket socket; public StreamReader reader; public StreamWriter writer; public Connection(Socket soc) { this.socket = soc; this.reader = new StreamReader(new NetworkStream(soc, false)); this.writer = new StreamWriter(new NetworkStream(soc, true)); new Thread(ClientLoop).Start(); } void ClientLoop() { lock (lck) { connections.Add(this); } while (true) { lock (lck) { string line = reader.ReadLine(); if (String.IsNullOrEmpty(line)) break; foreach (Connection con in cons) con.writer.WriteLine(line); } } lock (lck) { cons.Remove(this); socket.Close(); } } } The problem I'm struggling to resolve is how to facilitate communication between the SerialPort instance and the threads. I'm not certain that the above code is the best way forward, so does anybody have another solution (the simpler the better)?

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• How do I handle the messages for a simple web-based live chat, on the server side?

  - by Carson Myers

  I'm building a simple live chat into a web application running on Django, but one thing I'm confused about is how I should store the messages between users. The chat will support multiple users, and a chat "session" is composed of users connected to one user that is the "host." The application is a sort of online document collaboration thing, so user X has a document, and users Y and Z would connect to user X to talk about the document, and that would be one chat session. If user Y disconnected for five minutes, and then signed back in and reconnected to user X, he should not get any of the messages shared between users X and Z while he was away. if users X, Y, and Z can have a chat session about user X's document, then users X and Y can connect to a simultaneous, but separate discussion about user Z's document. How should I handle this? Should I keep each message in the database? Each message would have an owner user and a target user (the host), and a separate table would be used to connect users with messages (which messages are visible to what users). Or should I store each session as an HTML file on the server, which messages get appended to? The problem is, I can't just send messages directly between clients. They have to be sent to the server in a POST request, and then each client has to periodically check for the messages in a GET request. Except I can't just have each message cleared after a client fetches it, because there could be multiple clients. How should I set this up? Any suggestions?

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• Paperclip: "missing" image when uses has_one

  - by EricR

  I'm working on a website that allows people who run bed and breakfast businesses to post their accommodations. I would like to require that they include a "profile image" of the accommodation when they post it, but I also want to give them the option to add more images later (this will be developed after). I thought the best thing to do would be to use the Paperclip gem and have a Accommodation and a Photo in my application, the later belonging to the first as an association. A new Photo record is created when they create an Accommodation. It has both id and accommodation_id attributes. However, the image is never uploaded and none of the Paperclip attributes get set (image_file_name: nil, image_content_type: nil, image_file_size: nil), so I get Paperclip's "missing" photo. Any ideas on this one? It's been keeping me stuck for a few days now. Accommodation models/accommodation.rb class Accommodation < ActiveRecord::Base validates_presence_of :title, :description, :photo, :thing, :location attr_accessible :title, :description, :thing, :borough, :location, :spaces, :price has_one :photo end controllers/accommodation_controller.erb class AccommodationsController < ApplicationController before_filter :login_required, :only => {:new, :edit} uses_tiny_mce ( :options => { :theme => 'advanced', :theme_advanced_toolbar_location => 'top', :theme_advanced_toolbar_align => 'left', :theme_advanced_buttons1 => 'bold,italic,underline,bullist,numlist,separator,undo,redo', :theme_advanced_buttons2 => '', :theme_advanced_buttons3 => '' }) def index @accommodations = Accommodation.all end def show @accommodation = Accommodation.find(params[:id]) end def new @accommodation = Accommodation.new end def create @accommodation = Accommodation.new(params[:accommodation]) @accommodation.photo = Photo.new(params[:photo]) @accommodation.user_id = current_user.id if @accommodation.save flash[:notice] = "Successfully created your accommodation." render :action => 'show' else render :action => 'new' end end def edit @accommodation = Accommodation.find(params[:id]) end def update @accommodation = Accommodation.find(params[:id]) if @accommodation.update_attributes(params[:accommodation]) flash[:notice] = "Successfully updated accommodation." render :action => 'show' else render :action => 'edit' end end def destroy @accommodation = Accommodation.find(params[:id]) @accommodation.destroy flash[:notice] = "Successfully destroyed accommodation." redirect_to :inkeep end private def check_owner end end views/accommodations/_form.html.erb <%= form_for @accommodation, :html => {:multipart => true} do |f| %> <%= f.error_messages %> <p> Title<br /> <%= f.text_field :title, :size => 60 %> </p> <p> Description<br /> <%= f.text_area :description, :rows => 17, :cols => 75, :class => "mceEditor" %> </p> <p> Photo<br /> <%= f.file_field :photo %> </p> [... snip ...] <p><%= f.submit %></p> <% end %> Photo The controller and views are still the same as when Rails generated them. models/photo.erb class Photo < ActiveRecord::Base attr_accessible :image_file_name, :image_content_type, :image_file_size belongs_to :accommodation has_attached_file :image, :styles => { :thumb=> "100x100#", :small => "150x150>" } end

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• When saving a model with has_one or has_many associations, which side of the association is saved fi

  - by SeeBees

  I have three simplified models: class Team < ActiveRecord::Base has_many :players has_one :coach end class Player < ActiveRecord::Base belongs_to :team validates_presence_of :team_id end class Coach < ActiveRecord::Base belongs_to :team validates_presence_of :team_id end I use the following code to test these models: t = Team.new team.coach = Coach.new team.save! team.save! returns true. But in another test: t = Team.new team.players << Player.new team.save! team.save! gives the following error: > ActiveRecord::RecordInvalid: > Validation failed: Players is invalid > from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/validations.rb:1090:in > `save_without_dirty!' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/dirty.rb:87:in `save_without_transactions!' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/transactions.rb:200:in > `save!' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/database_statements.rb:136:in > `transaction' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/transactions.rb:182:in > `transaction' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/transactions.rb:200:in > `save!' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/transactions.rb:208:in > `rollback_active_record_state!' from > /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/transactions.rb:200:in > `save!' from (irb):14 I figured out that when team.save! is called, it first calls player.save!. player needs to validate the presence of the id of the associated team. But at the time player.save! is called, team hasn't been saved yet, and therefore, team_id doesn't yet exist for player. This fails the player's validation, so the error occurs. But on the other hand, team is saved before coach.save!, otherwise the first example will get the same error as the second one. So I've concluded that when a has_many bs, a.save! will save bs prior to a. When a has_one b, a.save! will save a prior to b. If I am right, why is this the case? It doesn't seem logical to me. Why do has_one and has_many association have different order in saving? Any ideas? And is there any way I can change the order? Say I want to have the same saving order for both has_one and has_many. Thanks.

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• How to use named_scope to incrementally construct a complex query?

  - by wbharding

  I want to use Rails named_scope to incrementally build complex queries that are returned from external methods. I believe I can get the behavior I want with anonymous scopes like so: def filter_turkeys Farm.scoped(:conditions => {:animal => 'turkey'}) end def filter_tasty Farm.scoped(:conditions => {:tasty => true}) end turkeys = filter_turkeys is_tasty = filter_tasty tasty_turkeys = filter_turkeys.filter_tasty But say that I already have a named_scope that does what these anonymous scopes do, can I just use that, rather than having to declare anonymous scopes? Obviously one solution would be to pass my growing query to each of the filter methods, a la def filter_turkey(existing_query) existing_query.turkey # turkey is a named_scoped that filters for turkey end But that feels like an un-DRY way to solve the problem. Oh, and if you're wondering why I would want to return named_scope pieces from methods, rather than just build all the named scopes I need and concatenate them together, it's because my queries are too complex to be nicely handled with named_scopes themselves, and the queries get used in multiple places, so I don't want to manually build the same big hairy concatenation multiple times.

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• NSNotification vs. Delegate Protocols?

  - by jr

  I have an iPhone application which basically is getting information from an API (in XML, but maybe JSON eventually). The result objects are typically displayed in view controllers (tables mainly). Here is the architecture right now. I have NSOperation classes which fetch the different objects from the remote server. Each of these NSOperation classes, will take a custom delegate method which will fire back the resulting objects as they are parsed, and then finally a method when no more results are available. So, the protocol for the delegates will be something like: (void) ObjectTypeResult:(ObjectType *)result; (void) ObjectTypeNoMoreResults; I think the solution works well, but I do end up with a bunch of delegate protocols around and then my view controllers have to implement all these delegate methods. I don't think its that bad, but I'm always on the lookout for a better design. So, I'm thinking about using NSNotifications to remove the use of the delegates. I could include the object in the userInfo part of the notification and just post objects as received, and then a final event when no more are available. Then I could just have one method in each view controller to receive all the data, even when using multiple objects in one controller.† So, can someone share with me some pros/cons of each approach. Should I consider refactoring my code to use Events rather then the delegates? Is one better then the other in certain situations? In my scenario I'm really not looking to receive notifications in multiple places, so maybe the protocol based delegates are the way to go. Thanks!

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• Are some DSL modems cheaper to operate than others? (power usage question)

  - by SetJmp

  I recently have started using a Motorola 2210 in conjunction with AT&T's DSL service in the Silicon Valley area. That gadget runs hot to the touch! Which means... I assume it is gobbling lots of electricity even when I am not using it. Has anyone studied this subject in a rigorous way? Which leads to the question... if the 2210 is very energy inefficient are some DSL modem models cheaper to operate than others? -SetJmp

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• Using JQuery in an AJAX control and avoiding conflicts

  - by Rich Andrews

  Hi, I am using JQuery within a custom AJAX user control (part of a home grown toolkit) and I need to ensure that JQuery is present on the hosting page. There can be multiple instances of the control on a page and some controls may need to use different versions of JQuery. At the moment I am using the following code to load in JQuery when the control initializes... Page.ClientScript.RegisterClientScriptInclude(Page.GetType(), "jquery-1.4.4.min.js", this.ResolveUrl("TextControlPlugin/lib/jquery-1.4.4.min.js")); This works because the scriptmanager handles not putting multiple copies of the same script into he page. Problems... I cannot use JQuery statically in the calling page (I may not have a control on the page but need to use JQuery) The scriptmanager appears to handle only duplicate URL's and I will need to deploy it from potentially 2 different URL's (the calling page's copy and the controls copy) So, is there a way to isolate a version of JQuery to the context of my control that doesnt interfear with any use of JQuery from the calling page? The developer writing the page may not have access to the internals of the control. I have looked at JQuery.noConflict() but cannot seem to get it to work correctly - I believe I'm having problems with the order in which the scripts are injected into the page - I keep getting JQuery is undefined errors. Any help would be much appreciated

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• Terminate function on System.in .. possible?

  - by Ronald

  I am currently working on a project where I have to make an agent to interact with a server. Each 50ms, the server will receive the last thing I outputted to System.out and send me a new set of lines as a 'state' through the System.in printstream to analyze and send my next message to System.out. Also, if the server receives multiple outputs from me, it only regards the most recent one. .. As for my question: My program originally constructed a tree and then analyzed each leaf node to see which would be optimal, and then waited around for the next input, but I can recursively do a deeper tree search that would make my output 'better' (and again and again to keep returning a better result). Using this and the fact that if the server receives multiple outputs, it only takes the most recent one, I could do each level, print my result and start the next level. But here comes my problem... I can't be stuck in some complex algorithm while I am supposed to receiving the next input as I will then miss it. So I was wondering if there is a way to cancel anything else I am doing when I receive something via System.in and then go back to the beginning of the function and start the search again with the new set of input (and rinse and repeat..) I hope this all makes sense, Thank ye all

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• Database schema for a library

  - by ABach

  Hi all - I'm designing a library management system for a department at my university and I wanted to enlist your eyes on my proposed schema. This post is primarily concerned with how we store multiple copies of each book; something about what I've designed rubs me the wrong way, and I'm hoping you all can point out better ways to tackle things. For dealing with users checking out books, I've devised three tables: book, customer, and book_copy. The relationships between these tables are as follows: Every book has many book_copies (to avoid duplicating the book's information while storing the fact that we have multiple copies of that book). Every user has many book_copies (the other end of the relationship) The tables themselves are designed like this: ------------------------------------------------ book ------------------------------------------------ + id + title + author + isbn + etc. ------------------------------------------------ ------------------------------------------------ customer ------------------------------------------------ + id + first_name + first_name + email + address + city + state + zip + etc. ------------------------------------------------ ------------------------------------------------ book_copy ------------------------------------------------ + id + book_id (FK to book) + customer_id (FK to customer) + checked_out + due_date + etc. ------------------------------------------------ Something about this seems incorrect (or at least inefficient to me) - the perfectionist in me feels like I'm not normalizing this data correctly. What say ye? Is there a better, more effective way to design this schema? Thanks!

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• Use MySQL trigger to update another table when duplicate key found

  - by Jason

  Been scratching my head on this one, hoping one of you kind people and direct me towards solving this problem. I have a mysql table of customers, it contains a lot of data, but for the purpose of this question, we only need to worry about 4 columns 'ID', 'Firstname', 'Lastname', 'Postcode' Problem is, the table contains a lot of duplicated customers. A new table is being created where each customer is unique and for us, we decide a unique customer is based on 'Firstname', 'Lastname' and 'Postcode' However, (this is the important bit) we need to ensure each new "unique" customer record also can be matched to the original multiple entries of that customer in the original table. I believe the best way to do this is to have a third table, that has 'NewUniqueID', 'OldCustomerID'. So we can search this table for 'NewUniqueID' = '123' and it would return multiple 'OldCustomerID' values where appropriate. I am hoping to make this work using a trigger and the on duplicate key syntax. So what would happen is as follows: An query is run taking the old customer table and inserting it in to the new unique table. (A standard Insert Select query) On duplicate key continue adding records, but add one entry in to the third table noting the 'NewUniqueID' that duped along with the 'OldCustomerID' of the record we were trying to insert. Hope this makes sense, my apologies if it isn't clear. I welcome and appreciate any thoughts on this one! Many thanks Jason

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• No grammar constraints (DTD or XML schema) detected for the document.

  - by fastcodejava

  I have this dtd : http://fast-code.sourceforge.net/template.dtd But when I include in an xml I get the warning : No grammar constraints (DTD or XML schema) detected for the document. The xml is : <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE templates PUBLIC "//UNKNOWN/" "http://fast-code.sourceforge.net/template.dtd"> <templates> <template type="type"> <description>Some</description> <variation></variation> <variation-field></variation-field> <allow-multiple-variation></allow-multiple-variation> <class-pattern></class-pattern> <getter-setter>setter</getter-setter> <allowed-file-extensions>java</allowed-file-extensions> <number-required-classes>1</number-required-classes> <template-body> <![CDATA[ Some Data ]]> </template-body> </template> </templates> Any clue?

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

  - by rdurbin

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

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• merge my code with Ajax code>>> problem

  - by sandy

  I want to help me In the following link i found nice code in Ajax http://www.w3schools.com/php/php_ajax_livesearch.asp I want to link my code with the code you see in the link above and replace dropdown list How can I do it for I could not where is it change in code even my code work as Ajax ?? I wish .... I wish .... I wish any somebody can help me <?php include ("connect.php"); print_r($_POST['sector_list']); $member_id = intval($_POST['sector_list']); if($member_id == 0) { // Default choice was selected } else { $res = mysql_query("SELECT * FROM members WHERE MemberID = $member_id LIMIT 1"); if(mysql_num_rows($res) == 0) { // Not a valid member } else { // The member is in the database } } ?> <form method="POST" action=<?php echo $_SERVER["PHP_SELF"]; ?> > <input type="hidden" name="sector" value="sector_list"> <select name="sector_list[]" class="inputstandard" multiple="multiple"> <option size ="40" value="default">send to </option> <?php $result = mysql_query('SELECT * from members') or die(mysql_error()); while ($row = mysql_fetch_assoc($result)) { echo '<option value="' . $row['MemberName'] . '">' . $row['MemberName']. '</option>'; } ?> <input type ="submit" name ="go" value = "go" > </select> </form>

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• Questions about the Backpropogation Algorithm

  - by Colemangrill

  I have a few questions concerning backpropogation. I'm trying to learn the fundamentals behind neural network theory and wanted to start small, building a simple XOR classifier. I've read a lot of articles and skimmed multiple textbooks - but I can't seem to teach this thing the pattern for XOR. Firstly, I am unclear about the learning model for backpropogation. Here is some pseudo-code to represent how I am trying to train the network. [Lets assume my network is setup properly (ie: multiple inputs connect to a hidden layer connect to an output layer and all wired up properly)]. SET guess = getNetworkOutput() // Note this is using a sigmoid activation function. SET error = desiredOutput - guess SET delta = learningConstant * error * sigmoidDerivative(guess) For Each Node in inputNodes For Each Weight in inputNodes[n] inputNodes[n].weight[j] += delta; // At this point, I am assuming the first layer has been trained. // Then I recurse a similar function over the hidden layer and output layer. // The prime difference being that it further divi's up the adjustment delta. I realize this is probably not enough to go off of, and I will gladly expound on any part of my implementation. Using the above algorithm, my neural network does get trained, kind of. But not properly. The output is always XOR 1 1 [smallest number] XOR 0 0 [largest number] XOR 1 0 [medium number] XOR 0 1 [medium number] I can never train the [1,1] [0,0] to be the same value. If you have any suggestions, additional resources, articles, blogs, etc for me to look at I am very interested in learning more about this topic. Thank you for your assistance, I appreciate it greatly!

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• Select return dynamic columns

  - by Ascalonian

  I have two tables: Standards and Service Offerings. A Standard can have multiple Service Offerings. Each Standard can have a different number of Service Offerings associated to it. What I need to be able to do is write a view that will return some common data and then list the service offerings on one line. For example: Standard Id | Description | SO #1 | SO #2 | SO #3 | ... | SO #21 | SO Count 1 | One | A | B | C | ... | G | 21 2 | Two | A | | | ... | | 1 3 | Three | B | D | E | ... | | 3 I have no idea how to write this. The number of SO columns is set to a specific number (21 in this case), so we cannot exceed past that. Any ideas on how to approach this? A place I started is below. It just returned multiple rows for each Service Offering, when they need to be on one row. SELECT * FROM SERVICE_OFFERINGS WHERE STANDARD_KEY IN (SELECT STANDARD_KEY FROM STANDARDS)

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• implementing a Intelligent File Transfer Software in java over TCP/IP

  - by whyjava

  Hello I am working on a proposal where we have to implement a software which can move files between one source to destination.The overall goal of this project is to create intelligent file transfer.This software will have three components :- 1) Broker : Broker is the module that communicates with other brokers, monitors files, moves files, retrieves configurations from the Configuration Manager, supplies process information for the monitor, archives files, writes all process data to log files and escalates issues if necessary 2) Configuration Manager :Configuration Manager is a web-based application used to configure and deploy the configuration to all brokers. 3) Monitor : Monitor is a web-based application used to monitor each Broker in the environment. This project has to be built up in java and protocol for file transfer in tcp/ip. Client does not want to use FTP. File Transfer seems very easy, until there are several processes who are waiting to pick the file up automatically. Several problems arise: How can we guarantee the file is received at the destination? If a file isn’t received the first time, we should try it again (even after a restart or power breakdown) ? How does the receiver knows the file that is received is complete? How can we transfer multiple files synchronously? How can we protect the bandwidth, so file transfer isn’t blocking other processes? How does one interoperate between multiple OS platforms? What about authentication? How can we monitor het workflow? Auditing / logging Archiving Can you please provide answer to some of these? Thanks

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• NSFetchedResultsController on secondary UITableView - how to query data?

  - by Jason

  I am creating a core-data based Navigation iPhone app with multiple screens. Let's say it is a flash-card application. The data model is very simple, with only two entities: Language, and CardSet. There is a one-to-many relationship between the Language entity and the CardSet entities, so each Language may contain multiple CardSets. In other words, Language has a one-to-many relationship Language.cardSets which points to the list of CardSets, and CardSet has a relationship CardSet.language which points to the Language. There are two screens: (1) An initial TableView screen, which displays the list of languages; and (2) a secondary TableView screen, which displays the list of CardSets in the Language. In the initial screen, which lists the languages, I am using NSFetchedResultsController to keep the list of languages up-to-date. The screen passes the Language selected to the secondary screen. On the secondary screen, I am trying to figure out whether I should again use an NSFetchedResultsController to maintain the list of CardSets, or if I should work through Language.cardSets to simply pull the list out of the object model. The latter makes the most sense programatically because I already have the Language - but then it would not automatically be updated on changes. I have looked at the NSFetchedResultsController documentation, and it seems like I can easily create predicates based on attributes - but not relationships. I.e., I can create the following NSFetchedResultsController: NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name LIKE[c] 'Chuck Norris'"]; How can I access my data through the direct relationship - Language.cardSets - and also have the table auto-update using NSFetchedResultsController? Is this possible?

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• How to write automated tests for SQL queries?

  - by James

  The current system we are adopting at work is to write some extremely complex queries which perform multiple calculations and have multiple joins / sub-queries. I don't think I am experienced enough to say if this is correct or not so I am agreeing and attempting to function with this system as it has clear benefits. The problem we are having at the moment is that the person writing the queries makes a lot of mistakes and assumes everything is correct. We have now assigned a tester to analyse all of the queries but this still proves extremely time consuming and stressful. I would like to know how we could create an automated procedure (without specifically writing it with code if possible as I can work out how to do that the long way) to verify a set of 10+ different inputs, verify the output data and say if the calculations are correct. I know I could write a script using specific data in the database and create a script using c# (the db is SQL Server) and verify all the values coming out but I would like to know what the official "standard" is as my experience is lacking in this area and I would like to improve. I am happy to add more information if required, add a comment if necessary. Thank you. Edit: I am using c#

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• Tree-like queues

  - by Rehno Lindeque

  I'm implementing a interpreter-like project for which I need a strange little scheduling queue. Since I'd like to try and avoid wheel-reinvention I was hoping someone could give me references to a similar structure or existing work. I know I can simply instantiate multiple queues as I go along, I'm just looking for some perspective by other people who might have better ideas than me ;) I envision that it might work something like this: The structure is a tree with a single root. You get a kind of "insert_iterator" to the root and then push elements onto it (e.g. a and b in the example below). However, at any point you can also split the iterator into multiple iterators, effectively creating branches. The branches cannot merge into a single queue again, but you can start popping elements from the front of the queue (again, using a kind of "visitor_iterator") until empty branches can be discarded (at your discretion). x -> y -> z a -> b -> { g -> h -> i -> j } f -> b Any ideas? Seems like a relatively simple structure to implement myself using a pool of circular buffers but I'm following the "think first, code later" strategy :) Thanks

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