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• source of historical stock data

  - by rmeador

  I'm trying to make a stock market simulator (perhaps eventually growing into a predicting AI), but I'm having trouble finding data to use. I'm looking for a (hopefully free) source of historical stock market data. Ideally, it would be a very fine-grained (second or minute interval) data set with price and volume of every symbol on NASDAQ and NYSE (and perhaps others if I get adventurous). Does anyone know of a source for such info? I found this question which indicates Yahoo offers historical data in CSV format, but I've been unable to find out how to get it in a cursory examination of the site linked. I also don't like the idea of downloading the data piecemeal in CSV files... I imagine Yahoo would get upset and shut me off after the first few thousand requests. I also discovered another question that made me think I'd hit the jackpot, but unfortunately that OpenTick site seems to have closed its doors... too bad, since I think they were exactly what I wanted. I'd also be able to use data that's just open/close price and volume of every symbol every day, but I'd prefer all the data if I can get it. Any other suggestions?

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• Manage multiple UDP calls

  - by rayman

  Hi all, I would like to have an advice for this issue: I am using Jbos 5.1.0, EJB3.0 I have system, which sending requests via UDP'S to remote modems, and suppose to wait for an answer from the target modem. the remote modems support only UDP calls, therefor I o design asynchronous mechanism. (also coz I want to request X modems parallel) this is what I try to do: all calls are retrieved from Data Base, then each call will be added as a message to JMS QUE. let's say i will set X MDB'S on that que, so I can work asynchronous. now each MDB will send UDP request to the IP-address(remote modem) which will be parsed from the que message. so basicly each MDB, which takes a message is sending a udp request to the remote modem and [b]waiting [/b]for an answer from that modem. [u]now here is the BUG:[/u] could happen a scenario where MDB will get an answer, but not from the right modem( which it requested in first place). that bad scenario cause two wrong things: a. the sender which sent the message will wait forever since the message never returned to him(it got accepted by another MDB). b. the MDB which received the message is not the right one, and probablly if it was on a "listener" mode, then it supposed to wait for an answer from diffrent sender.(else it wouldnt get any messages) so ofcourse I can handle everything with a RETRY mechanisem. so both mdb's(the one who got message from the wrong sender, and the one who never got the answer) will try again, to do thire operation with a hope that next time it will success. This is the mechanism, mybe you could tell me if there is any design pattren, or any other effective solution for this problem? Thanks, ray.

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• Passing IDisposable objects through constructor chains

  - by Matt Enright

  I've got a small hierarchy of objects that in general gets constructed from data in a Stream, but for some particular subclasses, can be synthesized from a simpler argument list. In chaining the constructors from the subclasses, I'm running into an issue with ensuring the disposal of the synthesized stream that the base class constructor needs. Its not escaped me that the use of IDisposable objects this way is possibly just dirty pool (plz advise?) for reasons I've not considered, but, this issue aside, it seems fairly straightforward (and good encapsulation). Codes: abstract class Node { protected Node (Stream raw) { // calculate/generate some base class properties } } class FilesystemNode : Node { public FilesystemNode (FileStream fs) : base (fs) { // all good here; disposing of fs not our responsibility } } class CompositeNode : Node { public CompositeNode (IEnumerable some_stuff) : base (GenerateRaw (some_stuff)) { // rogue stream from GenerateRaw now loose in the wild! } static Stream GenerateRaw (IEnumerable some_stuff) { var content = new MemoryStream (); // molest elements of some_stuff into proper format, write to stream content.Seek (0, SeekOrigin.Begin); return content; } } I realize that not disposing of a MemoryStream is not exactly a world-stopping case of bad CLR citizenship, but it still gives me the heebie-jeebies (not to mention that I may not always be using a MemoryStream for other subtypes). It's not in scope, so I can't explicitly Dispose () it later in the constructor, and adding a using statement in GenerateRaw () is self-defeating since I need the stream returned. Is there a better way to do this? Preemptive strikes: yes, the properties calculated in the Node constructor should be part of the base class, and should not be calculated by (or accessible in) the subclasses I won't require that a stream be passed into CompositeNode (its format should be irrelevant to the caller) The previous iteration had the value calculation in the base class as a separate protected method, which I then just called at the end of each subtype constructor, moved the body of GenerateRaw () into a using statement in the body of the CompositeNode constructor. But the repetition of requiring that call for each constructor and not being able to guarantee that it be run for every subtype ever (a Node is not a Node, semantically, without these properties initialized) gave me heebie-jeebies far worse than the (potential) resource leak here does.

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• jQuery crashing Internet Explorer

  - by Bradley Bell

  Hello. Okay basically, I'm designing and developing a fairly complicated website which revolves around the use of jQuery.. My knowlege of jQuery is really poor and this is the first time I've properly used it. I posted a question here before about the script and apparently its awful, but I didn't show you exactly what I was actually writing it for, which I can now.. Because I've uploaded it onto a test directory. It now works fine in every browser other than IE. The CSS styling is getting there and it should be close to finish soon! However, Internet Explorer is showing bad problems.. In IE 7,8 it looks fine but when you go to hover over a link, it immediately crashes. IE 6, the display doesn't seem to be working properly at all. But IE 6 is a lesser problem. If you could take just 5 or 10 minutes to potentially rewrite a simple script which would potentially take me 10 hours, I would be so so grateful! Heres the site - http://openyourheart.org.uk/test/index.html I can send all the files zipped if required. Thankyou in advance. Bradley

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• ruby/datamapper: Refactor class methods to module

  - by DeSchleib

  Hello, i've the following code and tried the whole day to refactor the class methods to a sperate module to share the functionality with all of my model classes. Code (http://pastie.org/974847): class Merchant include DataMapper::Resource property :id, Serial [...] class << self @allowed_properties = [:id,:vendor_id, :identifier] alias_method :old_get, :get def get *args [...] end def first_or_create_or_update attr_hash [...] end end end I'd like to archive something like: class Merchant include DataMapper::Resource include MyClassFunctions [...] end module MyClassFunctions def get [...] def first_or_create_or_update[...] end => Merchant.allowed_properties = [:id] => Merchant.get( :id=> 1 ) But unfortunately, my ruby skills are to bad. I read a lot of stuff (e.g. here) and now i'm even more confused. I stumbled over the following two points: alias_method will fail, because it will dynamically defined in the DataMapper::Resource module. How to get a class method allowed_properties due including a module? What's the ruby way to go? Many thanks in advance.

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• Interface for reading variable length files with header and footer.

  - by John S

  I could use some hints or tips for a decent interface for reading file of special characteristics. The files in question has a header (~120 bytes), a body (1 byte - 3gb) and a footer (4 bytes). The header contains information about the body and the footer is only a simple CRC32-value of the body. I use Java so my idea was to extend the "InputStream" class and add a constructor such as "public MyInStream( InputStream in)" where I immediately read the header and the direct the overridden read()'s the body. Problem is, I can't give the user of the class the CRC32-value until the whole body has been read. Because the file can be 3gb large, putting it all in memory is a be an idea. Reading it all in to a temporary file is going to be a performance hit if there are many small files. I don't know how large the file is because the InputStream doesn't have to be a file, it could be a socket. Looking at it again, maybe extending InputStream is a bad idea. Thank you for reading the confused thoughts of a tired programmer. :)

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• Good practice to create extension methods that apply to System.Object?

  - by Christian

  Hello, I'm wondering whether I should create extension methods that apply on the object level or whether they should be located at a lower point in the class hierarchy. What I mean is something along the lines of: public static string SafeToString(this Object o) { if (o == null || o is System.DBNull) return ""; else { if (o is string) return (string)o; else return ""; } } public static int SafeToInt(this Object o) { if (o == null || o is System.DBNull) return 0; else { if (o.IsNumeric()) return Convert.ToInt32(o); else return 0; } } //same for double.. etc I wrote those methods since I have to deal a lot with database data (From the OleDbDataReader) that can be null (shouldn't, though) since the underlying database is unfortunately very liberal with columns that may be null. And to make my life a little easier, I came up with those extension methods. What I'd like to know is whether this is good style, acceptable style or bad style. I kinda have my worries about it since it kinda "pollutes" the Object-class. Thank you in advance & Best Regards :) Christian P.S. I didn't tag it as "subjective" intentionally.

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• Domain model: should things like Logging, Audit, Persistence be in it

  - by hom.tanks

  I'm having a hard time convincing our architect that a Domain model should only have the essential elements of the business domain on it. Things like the fact that a class is persistable, that it needs logging and auditing and that it has a RESTful URI should not drive the domain model. They can be added later on, by using interfaces. Ours is a healthcare information management system. At the very coarse level, its a system where users login and access their healthcare information. They can share this information with others and be custodian for others' information (think Roles). But because of a few sound bytes that caught on early like "Everything should be a REST resource" the model now has a top level class called Resource that every other class extends from. I'm trying to make him see that the domain model should have well defined concepts like User Account, HealthDocument, UserRole etc which are distinct entities of the business , with specific associations between them. Clubbing everything under Resource class lets our model be inflexible besides being potentially incorrect. But he wants me to show him why its a bad idea to do it his way. I don't know how to articulate that properly but all my OO instincts tell me that its just not right. Any thoughts?

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• ASP.NET MVC2 and Browser Caching

  - by Dan

  Hi I have a web application that fetches a lot of content via ajax. For example when a user edits some data, the browser will send the changes using an ajax post and then do an ajax get to get fresh content and replace an existing div on the page with that content. This was working just find with MVC1, but in MVC2 I would get inconsistent results. I've found that MVC1 by default included an Expires item in the response headers set to the current time, but in MVC2 the Expires header is missing. This is a problem with some browsers (IE8) actually using the cached version of the ajax get instead of the fresh version. To deal with the problem I created a simple ActionFilterAttribute that sets the reponse cache to NoCache (see below), which works, but it seems kind of sillly to decorate every controller with this attribute. Is there a global way to set this for every controller? Is this a bug in MVC2 and it really should be setting the expires on every ActionResult/view/page? Don't most MVC programs deal with data entry where stale data is a very bad thing? Thanks Dan public class ResponseNoCachingAttribute : ActionFilterAttribute { public override void OnResultExecuted(ResultExecutedContext filterContext) { base.OnResultExecuted(filterContext); filterContext.HttpContext.Response.Cache.SetCacheability(System.Web.HttpCacheability.NoCache); } }

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• Could my forms be hacked.

  - by Mike Sandman

  Hi there, I posted a question yesterday, which I intend to get back to today however I wrote some JavaScript as a first line of prevention against XSS. However when testing this on my live server I catch some invalid input as the javascript catches the php section. My form uses post and php isn't in my form items (i haven't typed it in). Could this be picking up the form action or something? I'm baffeled, Any ideas Here is my code, it is triggered on the submit button. function validateForBadNess(){ var theShit = new Array("*","^", "$", "(",")","{", "}","[", "]","\", "|", "'","/","?",",","=","","gt","lt", "<","script","`","´","php"); var tagName = new Array(); tagName[0] = "input"; tagName[1] = "select"; tagName[2] = "textbox"; tagName[3] = "textarea"; for (ms=0;ms // loop through the elements of the form var formItems = document.getElementsByTagName(tagName[ms]); for (var xs=0;xs var thisString = formItems[xs].value; // loop through bad array for (zs in theShit){ //alert(thisString + " " + thisString.indexOf(theShit[zs])) if(thisString.indexOf(theShit[zs]) >= 0){ alert("Sorry but the following character: " + theShit[zs] + " is not permitted. Please omit it from your input.\nIf this is part of your password please contact us to heave your password reset.") return false; } } // loop for formitems } // tagName toop } // original condition }

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• PHP Redirection with Post Parameters

  - by arik-so

  Hello, I have a webpage. This webpage redirects the user to another webpage, more or less the following way: <form method="post" action="anotherpage.php" id="myform"> <?php foreach($_GET as $key => $value){ echo "<input type='hidden' name='{$key}' value='{$value}' />"; } ?> </form> <script> document.getElementById('myform').submit(); </script> Well, you see, what I do is transferring the GET params into POST params. Do not tell me it is bad, I know that myself, and it is not exactly what I really do, what is important is that I collect data from an array and try submitting it to another page via POST. But if the user has JavaScript turned off, it won't work. What I need to know: Is there a way to transfer POST parameters by means of PHP so the redirection can be done the PHP way (header('Location: anotherpage.php');), too? It is very important for me to pass the params via POST. I cannot use the $_SESSION variable because the webpage is on another domain, thus, the $_SESSION variables differ. Anyway, I simply need a way to transfer POST variables with PHP ^^ Thanks in advance!

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• Custom Wordpress Post Page Breaks if More Thank 2 Posts?

  - by thatryan

  I have a very custom template, and it works great if there are 1 or 2 posts on the blog page. But as soon as a 3rd post is added, it alters the structure of the template... Literally moves a div inside of another and I can not understand why. The code for the blog template is here, and a screenshot of the structure as it should be and another showing the misplaced div when a third post is there. Does this make any sense, any ideas? Thank you much! <div class="post" id="post-<?php the_ID(); ?>"><!--start post--> <h2><?php the_title(); ?></h2> <div id="main_full" class=" clearfix"><!--start main--> <div id="top_bar"><h3 class="gallery-title">news</h3></div> <div id="blog_page"><!--start blog page--> <div class="entry"><!--start entry--> <?php the_content(); ?> </div><!--end entry--> </div><!--end blog page--> </div><!--end main--> <?php endwhile; endif; ?> </div><!--end post--> <?php edit_post_link('Edit this entry.', '<p>', '</p>'); ?> <?php comments_template(); ?> Good One Bad One

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• Deterministic and non uniform long string generation from seed

  - by Limonup

  I had this weird idea for an encryption that I wanted to try out, it may be bad, and it may have done before, but I'm just doing it for fun. The short version of the question is: Is it possible to generate a long, deterministic and non-uniformly distributed string/sequence of numbers from a small seed? Long(er) version: I was thinking to encrypt a text by changing encoding. The new encoding would be generated via Huffman algorithm. To work well, the Huffman algorithm would need a fairly long text with non uniform distribution. Then characters can have different bit-lengths which would be the primary strength of this encryption. The problem is that its impractical to enter in/remember a long text each time you want to decrypt the text. So I was wondering if it was possible to generate a text from password seed? It doesn't matter what the text is, as long as it has non uniform distribution of characters and that the exact same sequence can be recreated each time you give it the same seed. Preferably, are there any functions/extensions in Python that can do this? EDIT: To expand on the "strength" of varying bit length: if I have a string "test", ASCII values 116, 101, 115, 116, which gives bit values of 1110100 1100101 1110011 1110100 Then, say my Huffman algorithm generates encoding like t = 101 e = 1100111 s = 10001 The final string is 101 1100111 10001 101, if we encode this back to ASCII, we get 1011100 1111000 1101000, which is 3 entirely different characters. Obviously its impossible to perform any kind of frequency analysis or something like that on this.

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• How should I progressively enhance this content with JavaScript?

  - by Sean Dunwoody

  The background to this problem is that I'm doing a computing project which involves Some drop down boxes for input, and a text input where the user can input a date. I've used YUI to enhance the form, so the calendar input uses the YUI calendar widget and the drop down list is converted into a horizontal list of inputs where the user only has to click once to select any input as opposed to two clicks with the drop down box (hope that makes sense, not sure how to explain it clearly) The problem is, that in the design section of my project I stated that I would follow the progressive enhancement principles. I am struggling however to ensure that users without JavaScript are able to view the drop down box / text input on said page. This is not because I do not necessarily know how, but the two methods I've tried seem unsatisfactory. Method 1 - I tried using YUI to hide the text box and drop down list, this seemed like the ideal solution however there was quite a noticeable lag when loading the page (especially for the first time), the text box and drop down list where visibile for at least a second. I included the script for this just before the end of the body tag, is there any way that I can run it onload with YUI? Would that help? Method 2 - Use the noscript tag . . . however I am loathed to do this as while it would be a simple solution, I have read various bad things about the noscript tag. Is there a way of making mehtod one work? Or is there a better way of doing this that I am yet to encounter?

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• how to edit a text message ( sms ) as it arrives in windows mobile 6 using managed code

  - by x86shadow

  I want to make an application to be installed on two pocket PCs and send Encrypted text messages and receive and decrypt them on the other device. I already made an application that gets special text messages ( starting with !farenc! ) and I know how to Encrypt/Decrypt the messages as well but I don't know how to edit a text message as it's arrive ( for decryption ). please help. thanks in advance and sorry for my bad English using System; using System.Linq; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; using Microsoft.WindowsMobile; using Microsoft.WindowsMobile.PocketOutlook; using Microsoft.WindowsMobile.PocketOutlook.MessageInterception; namespace SMSDECRYPT { public partial class Form1 : Form { MessageInterceptor _SMSCatcher = new MessageInterceptor(InterceptionAction.Notify, true); MessageCondition _SMSFilter = new MessageCondition(); public Form1() { InitializeComponent(); _SMSFilter.Property = MessageProperty.Body; _SMSFilter.ComparisonType = MessagePropertyComparisonType.StartsWith; _SMSFilter.CaseSensitive = true; _SMSFilter.ComparisonValue = "!farenc!"; _SMSCatcher.MessageCondition = _SMSFilter; _SMSCatcher.MessageReceived += new MessageInterceptorEventHandler(_SMSCatcher_MessageReceived); } private void Form1_Load(object sender, EventArgs e) { //... } void _SMSCatcher_MessageReceived(object sender, MessageInterceptorEventArgs e) { SmsMessage mySMS = (SmsMessage)e.Message; string sms = mySMS.Body.ToString(); sms = sms.Substring(8); //Decryption //... //Update the received message and replace it with the decrypted text //!!!HELP!!! } } }

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• How to fetch and populate backbone model for Google Places JS API?

  - by code-gijoe

  I'm implementing a system that require access to Google Places JS API. I've been using rails for most of the project, but now I want to inject a bit of AJAX in one of my views. Basically it is a view that displays places near your location. For this, I'm using the JS API of Google places. A quick workflow would be: 1- The user inputs a text query and hits enter. 2- There is an AJAX call to request data from Google Places API. 3- The successful result is presented to the user. The problem is primarily in step 2. I want to use backbone for this but when I create a backbone model, it requests to the 'rootURL'. This wouldn't be a problem if the requests to Places was done from the server but it is not. A place call is done like this: service = new google.maps.places.PlacesService(map); service.nearbySearch(request, callback); Passing a callback function: function callback(results, status) { if (status == google.maps.places.PlacesServiceStatus.OK) { for (var i = 0; i < results.length; i++) { var place = results[i]; createMarker(results[i]); } } } Is it possible to override the 'fetch' method in backbone model and populate the model with the successful Places result? Is this a bad idea?

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• The rules to connect a web service trough the SSL and Certificates

  - by blgnklc

  There is a web service running on tomcat on a server. It is built on Java Servlet. It is listening others to call itself on a SSL enabled http port. so its web service adreess looks like: https://172.29.12.12/axis/services/XYZClient?wsdl On the other hand I want to connect the web service above from a windows application which is built on .NET frame work. Finally, when I want to connect the web service from my computer; I get some specific erros; Firstly I get; Proxy authentication error; then I added some new line to my code; Dim cr As System.Net.NetworkCredential = New System.Net.NetworkCredential("xname", "xsurname", "xdomainname") Dim myProxy As New WebProxy("http://mar.xxxyyy.com", True) myProxy.Credentials = cr Secondly, after this modifications It says that bad request. I did not get over this error. Moreover I did try to connect the web server on the same computer. I copied my executable program to the computer where the web service runs. The error was like; The underlying connection was closed: Could not establish trust relationship for SSL/TLS secure channel PS: When I try to connect to web service by using Internet Explorer; I see firstly some warnings about accepting an unknown certificate and I click take me to web service an I get there clearly. I want to know what are the basic elements to connect a web service, could you please tell me the requirements that I have to use on my windows project. regards bk

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• Python subprocess: 64 bit windows server PIPE doesn't exist :(

  - by Spaceman1861

  I have a GUI that launches selected python scripts and runs it in cmd next to the gui window. I am able to get my launcher to work on my (windows xp 32 bit) laptop but when I upload it to the server(64bit windows iss7) I am running into some issues. The script runs, to my knowledge but spits back no information into the cmd window. My script is a bit of a Frankenstein that I have hacked and slashed together to get it to work I am fairly certain that this is a very bad example of the subprocess module. Just wondering if i could get a hand :). My question is how do i have to alter my code to work on a 64bit windows server. :) from Tkinter import * import pickle,subprocess,errno,time,sys,os PIPE = subprocess.PIPE if subprocess.mswindows: from win32file import ReadFile, WriteFile from win32pipe import PeekNamedPipe import msvcrt else: import select import fcntl def recv_some(p, t=.1, e=1, tr=5, stderr=0): if tr < 1: tr = 1 x = time.time()+t y = [] r = '' pr = p.recv if stderr: pr = p.recv_err while time.time() < x or r: r = pr() if r is None: if e: raise Exception(message) else: break elif r: y.append(r) else: time.sleep(max((x-time.time())/tr, 0)) return ''.join(y) def send_all(p, data): while len(data): sent = p.send(data) if sent is None: raise Exception(message) data = buffer(data, sent) The code above isn't mine def Run(): print filebox.get(0) location = filebox.get(0) location = location.__str__().replace(listbox.get(ANCHOR).__str__(),"") theTime = time.asctime(time.localtime(time.time())) lastbox.delete(0, END) lastbox.insert(END,theTime) for line in CookieCont: if listbox.get(ANCHOR) in line and len(line) > 4: line[4] = theTime else: "Fill In the rip Details to record the time" if __name__ == '__main__': if sys.platform == 'win32' or sys.platform == 'win64': shell, commands, tail = ('cmd', ('cd "'+location+'"',listbox.get(ANCHOR).__str__()), '\r\n') else: return "Please use contact admin" a = Popen(shell, stdin=PIPE, stdout=PIPE) print recv_some(a) for cmd in commands: send_all(a, cmd + tail) print recv_some(a) send_all(a, 'exit' + tail) print recv_some(a, e=0) The Code above is mine :)

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• FQL query using stream table doesn't accept app access token

  - by tougher

  I've searched stackoverflow all day long to find an answer without luck, so here we go. I'm trying to fetch data from the stream table like this: FQL: SELECT post_id, message, created_time FROM stream WHERE source_id = 131559313586863 URL: http:// graph.facebook.com/fql?q=SELECT+post_id%2C+message%2C+created_time+FROM+stream+WHERE+source_id+%3D+131559313586863&access_token=10669xxxxx74470|PF-7GSdBx0Nxxxxxkdi1KwSQG-w But I get a 400 Bad Request as response with the error message: "An access token is required to request this resource.". I'm fetching an application access token with this url: https:// graph.facebook.com/oauth/access_token?client_id=FACEBOOK_APP_ID&client_secret=FACEBOOK_APP_SECRET&grant_type=client_credentials Facebook state in this blog post that "You will need to pass a valid app or user access token to access this functionality.". Functionality refers to /feed and /posts (the stream table). Futhermore this wiki tells the same story about using the stream table, "From June 3 2011 a token is required to query this table. You can use any application or user token to make the query.". Does anyone see my hopefully obvious flaw? Please note: The profile in the FQL query is public. I need this to run userless though a cronjob. No user interaction is possible. The request works if I replace the app access token with my own user token from https:// developers.facebook.com/tools/explorer Sorry for breaking the URL's. I need more reputation to post more than 2 links :-/

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• Why does adding Crossover to my Genetic Algorithm give me worse results?

  - by MahlerFive

  I have implemented a Genetic Algorithm to solve the Traveling Salesman Problem (TSP). When I use only mutation, I find better solutions than when I add in crossover. I know that normal crossover methods do not work for TSP, so I implemented both the Ordered Crossover and the PMX Crossover methods, and both suffer from bad results. Here are the other parameters I'm using: Mutation: Single Swap Mutation or Inverted Subsequence Mutation (as described by Tiendil here) with mutation rates tested between 1% and 25%. Selection: Roulette Wheel Selection Fitness function: 1 / distance of tour Population size: Tested 100, 200, 500, I also run the GA 5 times so that I have a variety of starting populations. Stop Condition: 2500 generations With the same dataset of 26 points, I usually get results of about 500-600 distance using purely mutation with high mutation rates. When adding crossover my results are usually in the 800 distance range. The other confusing thing is that I have also implemented a very simple Hill-Climbing algorithm to solve the problem and when I run that 1000 times (faster than running the GA 5 times) I get results around 410-450 distance, and I would expect to get better results using a GA. Any ideas as to why my GA performing worse when I add crossover? And why is it performing much worse than a simple Hill-Climb algorithm which should get stuck on local maxima as it has no way of exploring once it finds a local max?

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• Multiple on-screen view controllers in iPhone apps

  - by Felixyz

  I'm creating a lot of custom views and controllers in a lot of my apps and so far I've mostly set them up programmatically, with adjustments and instantiations being controlled from plists. However, now I'm transitioning to using Interface Builder as much as possible (wish I had done that before, was always on my back-list). Apple is recommending against having many view controllers being simultaneously active in iPhone apps, with a couple of well-known exceptions. I've never fully understood why it should be bad to have different parts of the interface belong to different controllers, if they have no interdependent functionality at all. Does having multiple controllers risk messing up the responder chain, or is there some other reason that it's not recommended, except for the fact that it's usually not needed? What I want to be able to do is design reusable views and controls in IB, but since a nib is not associated with a view, but with a view controller, it seems I'd have to have different parts of the screen be connected to different controllers. I know it's possible to have other objects than view controllers being instantiated from nibs. Should I look into how to create my own alternative more light-weight controllers (that could be sub-controllers of a UIViewController) which could be instantiated from nibs?

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• Why are a visual studio project's command-line settings stored per user? Is it OK to check-in (and

  - by DanO

  We're creating an application that understands some command-line parameters. There are some default's we would like to supply on the command-line when debugging, and these are easily set in the project settings as explained here. The thing is visual studio stores these settings in a *.csproj.user file, and the default settings for integrated source control do not check-in *.user files. We would like to just have these default command-line parameters in everyone's IDE when debugging this project. Often (but not always) when visual studio guides you into doing things a certain way it is for good reason. We probably don't want to just check-in someone's .csproj.user file... right? This question is has a few parts: Why does Visual Studio store this particular setting per user? Is there a way to alter this behavior? - Would doing so bring bad juju? Under these circumstances is it OK to check-in and share a .user file? Is there a better way to accomplish what we are trying to do here? Thank you -

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• What arguments to use to explain why a SQL DB is far better then a flat file

  - by jamone

  The higher ups in my company were told by good friends that flat files are the way to go, and we should switch from MS SQL server to them for everything we do. We have over 300 servers and hundreds of different databases. From just the few I'm involved with we have 10 billion records in quite a few of them with upwards of 100k new records a day and who knows how many updates... Me and a couple others need to come up with a response saying why we shouldn't do this. Most of our stuff is ASP.NET with some legacy ASP. We thought that making a simple console app that tests/times the same interactions between a flat file (stored on the network) and SQL over the network doing large inserts, searches, updates etc along with things like network disconnects randomly. This would show them how bad flat files can be espically when you are dealing with millions of records. What things should I use in my response? What should I do with my demo code to illustrate this? My sort list so far: Security Concurent access Performance with large ammounts of data Ammount of time to do such a massive rewrite/switch Lack of transactions PITA to map relational data to flat files I fear that this will be a great post on the Daily WTF someday if I can't stop it now.

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• How to store an inventory using hashtables?

  - by Harm De Weirdt

  Hello everyone. For an assignment in collego we have to make a script in Perl that allows us to manage an inventory for an e-store. (The example given was Amazon) Users can make orders in a fully text-based environment and the inventory must be updated when an order is completed. Every item in the inventory has 3 to 4 attributes: a product code, a title, a price and for some an amount (MP3's for example do not have this attribute) Since this is my first encounter with Perl, i don't really know how to start. My main problem is how i should "implement" the inventory in the program. One of the functions of the program is searching trough the titles. Another is to make an order, where the user should give a product code. My first idea was a hashtable with the productcode as key. But if i wanted to search in the titles that could be a problem because of this: the hashkey would be something like DVD-123, the information belonging to that key could be "The Green Mask 12" (without the ") where the 12 indicates how many of this DVD are currently in stock. So i'd have to find a way to ignore the 12 in the end. Another solution was to use the title as Hashkey, but that would prove cumbersome too I think. Is there a way to make a hashtable with 2 key's, and when I give only one it returns an array with the other values? (Including the other key and the other information) That way I could use another key depending on what info I need from my inventory. We have to read the default inventory from a txt file looking like this: MP3-72|Lady Gaga - Kiss and Run (Fear of Commitment Monster)|0.99 CD-400|Kings of Leon - Only By The Night|14.50|2 MP3-401|Kings of Leon - Closer|0.85 DVD-144|Live Free or Die Hard|14.99|2 SOFT-864|Windows Vista|49.95 Any help would be appreciated very much :) PS: I am sorry for my bad grammar, English isn't my native language.

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• How does a client find the port number of a server?

  - by Jonathan

  Hello all, I am currently learning about basic networking in java. I have been playing around with the server and client relationship between two of my computers. However, I cannot figure out how distributed programs (say, a videogame), can not only find the 'host' computer, but also the port number on which the server is running in order to create a Socket between the two computers. The only way I really see to create a Socket is with an already known IP Address, and with a known port number. How do you search a LAN network for another computer (host) searching for clients? How do you determine what port the server is located on without 'pinging' all available ports for a response (which, I understand, is bad form... Something about 'server attack'...)? In such a situation as a video game, there can be any number of computers on the same network, and any number of them might be attempting to host, or otherwise running the application. Any other important information, or perhaps reference to a more detailed tutorial than the one I am using, regarding making connections on so very little information on the client side would be appreciated. Many thanks, Jonathan

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