Search Results

Search found 25440 results on 1018 pages for 'agent based modeling'.

Page 600/1018 | < Previous Page | 596 597 598 599 600 601 602 603 604 605 606 607  | Next Page >

• Hosting and scaling of a facebook application on cloud?

  - by DhruvPathak

  We would be building a facebook application in django(Python), but still not sure of where to host it economically,and with a good provision to scale in case the app gets viral. Some details about the app: i) Would be HTML based like a website,using django as a framework. ii) 100K is the number of expected pageviews in a day,if the app is viral. iii) The users will not generate any media content,only some database data will be generated by them. It would be great if someone with more experience can guide on following points: A) Hosting on google app engine or Amazon EC2 or some other cloud like RackSpace : Preferable points found in AppEngine were ease of deployment,cost effectiveness and easy scaling. For EC2: Full hold of the virtual machine,Amazon NoSQL and RDMBS database services in case we decide to use them. B) Does backend technology affect monthly cost ? eg. would CPU and memory usage difference of Django over , for example , PHP framework like CodeIgnitor really make remarkable difference in running costs. ( Here is the article that triggered this thought process : http://journal.dedasys.com/2010/01/12/rough-estimates-of-the-dollar-cost-of-scaling-web-platforms-part-i#comments) C) Does something like Heroku , which provides additional services over Amazon EC2, prove to be better than raw cloud management ? It is not that we are trying for premature scaling, we just want to have a good start so that we are ready to handle unpredicted growth and scale.

  Read the article

• update terminal title from standard output of long running command?

  - by Sam Hasler

  I'd like to change the title of a terminal window during a long running command (for example: git svn fetch) with values greped from the output, whilst still writing to standard output. Is this possible using named pipes or tee and xargs? I'm thinking something like git svn fetch | sed "s/^\(r\d*\).*$/ \"\\\033]0;\"\1\"\\\007\"/" | xargs -l1 echo -ne based on: http://tldp.org/HOWTO/Xterm-Title-3.html Update: getting this to work would be enough: (echo "r9" ; echo "r10") | sed "s/^\(r\d*\).*$/ \"\\\033]0;\"\1\"\\\007\"/" | xargs -l1 echo -ne Update 2: This almost does what I want. I see r10, but not r9: (echo "r9" ; sleep 1 ; echo "r10") | sed "s/^\(r[0-9]*\)\.*$/\\\033]0;\1\\\007/" | xargs -0 echo -ne

  Read the article

• General High-Level Assessment

  - by tcarper

  Guys and Gals, I've been tasked with a doozy of an assignment. The objective is something akin to "laying of hands" on several database servers which work in concert to provide data to various Web, Client-Server and Tablet-Sync'd distributed Client-Server programs. More specifically, I've been asked to come up with a "Maintenance Plan" which includes recommendations for future work to improve these machines' performance/reliability/security/etc. Might there be some good articles on teh interwebs ya'll could point me towards which would give me some good basis to start? Articles describing "These are the top 4 overarching categories and this is how you should proceed when drilling down on each of them" sort-of-thing would be fabulous. The Databases are all SQL 2005, however the compatibility level is 80 and they were originally created with ERwin based on SQL 6.5. The OSs are all Windows Server 2003. Thanks all! Tim

  Read the article

• Question about a simple design problem

  - by Uri

  At work I stumbled uppon a method. It made a query, and returned a String based on the result of the query, such as de ID of a customer. If the query didn't return a single customer, it'd return a null. Otherwise, it'd return a String with the ID's of them. It looked like this: String error = getOwners(); if (error != null) { throw new Exception("Can't delete, the flat is owned by: " + error); } ... Ignoring the fact that getCustomers() returns a null when it should instead return an empty String, two things are happening here. It checks if the flat is owned by someone, and then returns them. I think a more readable logic would be to do this: if (isOwned) { throw new Exception("Can't delete, the flat is owned by: " + getOwners()); } ... The problem is that the first way does with one query what I do with two queries to the database. What would be a good solution involving good design and efficiency for this?

  Read the article

• Hash Algorithm Randomness Visualization

  - by clstroud

  I'm curious if anyone here has any idea how the images were generated as shown in this response: Which hashing algorithm is best for uniqueness and speed? Ian posted a very well-received response but I can't seem to understand how he went about making the images. I hate to make a new question dedicated to this, but I can't find any means to ask him more directly. On the other hand, perhaps someone has an alternative perspective. The best I can personally come up with would be to have it almost like a bar graph, which would illustrate how evenly the buckets of the hash table are being generated. I have a working Cocoa program that does this, but it can't generate anything like what he showed there. So the question is two fold I suppose: A) How does one truly interpret the data he shows? Is it more than "less whitespace = better"? B) How does one generate such an image based on some set of inputs, a hash, and an index? Perhaps I'm misunderstanding entirely, but I really would like to know more about this particular visualization technique. Or maybe I'm mis-applying this to hash tables rather than just hashes in general, but in that case I don't know how it would be "bounded" for the image.

  Read the article

• can canonical links be used to make 'duplicate' pages unique?

  - by merk

  We have a website that allows users to list items for sale. Think ebay - except we don't actually deal with selling the item, we just list it for sale and provide a way to contact the seller. Anyhow, in several cases sellers maybe have multiple units of an item for sale. We don't have a quantity field, so they upload each item as a separate listing (and using a quantity field is not an option). So we have a lot of pages which basically have the exact same info and only the item # might be different. The SEO guy we've started using has said we should put a canonical link on each page, and have the canonical link point to itself. So for example, www.mysite.com/something/ would have a canonical link of href="www.mysite.com/something/" This doesn't really seem kosher to me. I thought canonical links we're suppose to point to other pages. The SEO guy claims doing it this way will tell google all these pages are indeed unique, even if they do basically have the same content. This seems a little off to me since what's to stop a spammer from putting up a million pages and doing this as well? Can anyone tell me if the SEO guy's suggestion is valid or not? If it's not valid, then do i need to figure out some way to check for duplicated items and automatically pick one of the duplicates to serve as an original and generate canonical links based off that? Thanks in advance for any help

  Read the article

• Android - Efficient way to draw tiles in OpenGL ES

  - by Maecky

  Hi, I am trying to write efficient code to render a tile based map in android. I load for each tile the corresponding bitmap (just one time) and then create the according tiles. I have designed a class to do this: public class VertexQuad { private float[] mCoordArr; private float[] mColArr; private float[] mTexCoordArr; private int mTextureName; private static short mCounter = 0; private short mIndex; As you can see, each tile has it's x,y location, a color array, texture coordinates and a texture name. Now, I want to render all my created tiles. To reduce the openGL api calls (I read somewhere that the state changes are costly and therefore I want to keep them to a minimum), I first want to hand ALL the coordinate-arrays, color-arrays and texture-coordinates over to OpenGL. After that I run two for loops. The first one iterates over the textures and binds the texture. The second for loop iterates over all Tiles and puts all tiles with the corresponding texture into an IndexBuffer. After the second for loop has finished, I call gl.gl_drawElements() whith the corresponding index buffer, to draw all tiles with the texture associated. For the next texture I do the same again. Now I run into some problems: Allocating and filling the FloatBuffers at the start of each rendering cycle costs very much time. I just run a test, where i wanted to put 400 coordinates into a FloatBuffer which took me about 200ms. My questions now are: Is there a better way, handling the coordinate and color structures? How is this correctly done, this is obviously not the optimal way? ;) thanks in advance, regards Markus

  Read the article

• Internet Explorer 9 is coming Monday to a web near you

  - by brian_ritchie

  Internet Explorer 9 is finally here...well almost.  Microsoft is releasing their new browser on March 14, 2011. IE9 has a number of improvements, including: Faster, Faster, Faster.  Did I mention it is faster?   With the new browsers coming out from Mozilla, Google, and Microsoft, there have been a flood of speed test coverage.  Chrome has long held the javascript speed crown.  But according to Steven J. Vaughan-Nichols over at ZDNET..."for the moment at least IE9 is actually the fastest browser I’ve tested to date."  He came to this revelation after figuring out that the 32-bit version of IE9 has the new Chakra JIT (the 64-bit version doesn't).  It also has a DirectX-based rendering engine so it can do cool tricks once reserved for desktop applications. Windows 7 Desktop Integration.  Read my post for more details.  Unfortantely, they didn't integrate my ideas...at least not yet :) Hot new UI.  Ok, they "borrowed" some ideas from Chrome...but that is the best form of flattery. Standards Compliance.  A real focus on HTML5 and CSS3.  Definite goodness for developers. So, go get yourself some IE9 on Monday and enjoy! 

  Read the article

• How can Facebook's session get mixed up because of NAT and/or Proxy

  - by Alex

  Have received some reports from a customer (a very large company) they reported issues from clients who are using Facebook. These clients claim that once in a while when they log in to Facebook they end up in someone else's session. I know that network is NATed then Proxied before getting to Facebook.com. Although I'm not able to explain how this issue can occur. Is it possible that the Proxy is not sending the right session back to the clients? How can they end up with someone else's session since Facebook is cookie based session?? Anyone seen this before?

  Read the article

• How can I use timer to stop another thread? [on hold]

  - by Haoda Fu

  How can we stop another thread based on a timer? I was trying to use timer to stop another thread. But I didn't got a success. To better illustrate my point and for your easy to understand the key issue. I made the following sample example. Your help is really appreciated using System; using System.Collections.Generic; using System.Text; using System.Threading; using System.Timers; namespace TestCodes { public static class Program { private static Thread nT = new Thread(PrintABC); private static System.Timers.Timer aTimer; public static void Main() { aTimer = new System.Timers.Timer(1000); aTimer.Elapsed += TimerCallback; aTimer.Interval = 1000; aTimer.Enabled = true; nT.Start(); Console.ReadLine(); } private static void TimerCallback(Object o, ElapsedEventArgs e) { nT.Join(); Console.WriteLine("Complete the PrintABC"); GC.Collect(); } private static void PrintABC() { for (int iter = 1; iter < 300; iter++) { Console.WriteLine(iter+"abc"); Console.ReadKey(); //Thread.Sleep(100); } } } }

  Read the article

• Using JCal Pro and Community Builder together for registration

  - by Kate

  Does anyone know if there is a way to use JCal Pro and Community Builder together in order to have users register for a specific event? When our new website was designed JCal Pro was implemented with the idea that individuals could look at the calendar and see what events they wanted to sign up for based spots open for that specific day. Now that we have more events and scheduling has become a major issue. For another project we installed CB in order to allow individuals to register and create profiles for an annual event. As I am looking at this nightmare I am living trying to organize various groupings of people I am assuming that there has to be some sort of a way to connect the two up so that those who have a user account through CB could also go in look at the calendar and sign up for an event. There is a JCal plug-in installed in CB however I have not had much luck at figuring out its functionality. I am running: Joomla 1.5.14 JCal Pro version 2.2.7.441 Community Builder: 1.2

  Read the article

• Tomcat + Spring + CI workflow

  - by ex3v

  We're starting our very first project with Spring and java web stack. This project will be mainly about rewriting quite large ERP/CRM from Zend Framework to Java. Important factor in my question is that I come from php territory, where things (in terms of quality) tend to look different than in java world. Fatcs: there will be 2-3 developers, at least one of developers uses Windows, rest uses Linux, there is one remote linux-based machine, which should handle test and production instances, after struggling with buggy legacy code, we want to introduce good programming and development practices (CI, tests, clean code and so on) client: internal, frequent business logic changes, scrum, daily deployments What I want to achieve is good workflow on as many development stages as possible (coding - commiting - testing - deploying). The problem is that I've never done this before, so I don't know what are best practices to do this. What I have so far is: developers code locally, there is vagrant instance on every development machine, managed by puppet. It contains the same linux, jenkins and tomcat versions as production machine, while coding, developer deploys to vagrant machine, after local merge to test branch, jenkins on vagrant handles tests, when everything is fine, developer pushes commits and merges jenkins on remote machine pulls commit from test branch, runs tests and so on, if everything looks green, jenkins deploys to test tomcat instance Deployment to production is manual (altough it can be done using helping scripts) when business logic is tested by other divisions and everything looks fine to client. Now, the real question: does above make any sense? Things that I'm not sure about: Remote machine: won't there be any problems with two (or even three, as jenkins might need one) instances of same app on tomcat? Using vagrant to develop on php environment is just vise. Isn't this overkill while using Tomcat? I mean, is there higher probability that tomcat will act the same on every machine? Is there sense of having local jenkins on vagrant?

  Read the article

• Overloading methods that do logically different things, does this break any major principles?

  - by siva.k

  This is something that's been bugging me for a bit now. In some cases you see code that is a series of overloads, but when you look at the actual implementation you realize they do logically different things. However writing them as overloads allows the caller to ignore this and get the same end result. But would it be more sound to name the methods more explicitly then to write them as overloads? public void LoadWords(string filePath) { var lines = File.ReadAllLines(filePath).ToList(); LoadWords(lines); } public void LoadWords(IEnumerable<string> words) { // loads words into a List<string> based on some filters } Would these methods better serve future developers to be named as LoadWordsFromFile() and LoadWordsFromEnumerable()? It seems unnecessary to me, but if that is better what programming principle would apply here? On the flip side it'd make it so you didn't need to read the signatures to see exactly how you can load the words, which as Uncle Bob says would be a double take. But in general is this type of overloading to be avoided then?

  Read the article

• Routing application traffic through specific interface

  - by UnicornsAndRainbows

  Hello All! First question here, so please go easy: I have a debian linux 5.0 server with two public interfaces. I would like to route outbound traffic from one instance of an application via one interface and the second instance through the second interface. There are some challenges: both instances of the application use the same protocol both instances of the application can access the entire internet (can't route based on dest network) I can't change the code of the application I don't think a typical approach to load balancing all traffic is going to work well, because there are relatively few destination servers being accessed in the outbound traffic, and all traffic would really need to be distributed pretty evenly across these relatively few servers. I could probably run two virtualized servers on the box and bind each of them to a different external ip, but I'm looking for a simpler solution, maybe using iproute or iptables? Any ideas for me? Thanks in advance - and I'm happy to answer any questions.

  Read the article

• Genetic Algorithm new generation exponentially increasing

  - by Rdz

  I'm programming Genetic Algorithm in C++ and after searching all kind of ways of doing GA'a operators (selection, crossover, mutation) I came up with a doubt. Let's say I have an initial population of 500. My selection will consist in getting the top 20% of 500(based on best fitness). So I get 100 individuals to mate. When I do the crossover I'll get 2 children where both together have 50% of surviving. So far so good. I start the mutation, and everything's ok.. Now when I start choosing the Next generation, I see that I have a big number of children (in this case, 4950 if you wanna know). Now the thing is, every time I run GA, if I send all the children to the next generation, the number of individuals per generation will increase exponentially. So there must be a way of choosing the children to fulfill a new generation without getting out of this range of the initial population. What I'm asking here is if there is anyway of choosing the children to fill the new generations OR should I choose somehow (and maybe reduce) the parents to mate so I don't get so many children in the end. Thanks :)

  Read the article

• Congratulations to 2012 Innovation Award winners in BPM category

  - by Manoj Das

  Last year many of our customers went live on BPM 11g. It is my extreme pleasure to congratulate two of them – Amadeus and Navistar – for being awarded Oracle Fusion Middleware Innovation Award at Oracle OpenWorld 2012. We invited our customers to submit their most innovative BPM implementations that have delivered substantiated value to them. This year we saw more than 20 submissions from our customers seeing significant business value from their live BPM 11g deployments. The submissions came from across the world, spanning various industry verticals including manufacturing, healthcare, logistics, Hi-Tech, Public Sector, Education and covering many process usage patterns. Award submissions were evaluated based on the uniqueness of their business case, business benefits, level of impact relative to the size of the organization, complexity and magnitude of implementation, and the originality of architecture. Amadeus Team Receiving Innovation Award from Hasan Rizvi Congratulations to Amadeus and Navistar and their teams on being recognized from among some very strong submissions and more importantly for the business value delivered. It is an honor to be part of your success and to play a small role in the innovation you drive. Navistar is a leading truck manufacturing company which produces International® brand commercial and military trucks, MaxxForce® brand diesel engines, IC Bus™ brand school and commercial buses, and Navistar RV brands of recreational vehicles. The company also provides truck and diesel engine service parts. Amadeus is a leading transaction processor for the global travel and tourism industry, providing transaction processing power and technology solutions to both travellers and travel providers. Both Navistar and Amadeus have leveraged Oracle BPM Suite to improve visibility into their business and made their business more agile and efficient. We congratulate them again and wish them continued success in their business and future BPM initiatives.

  Read the article

• KVM to Xen migration

  - by qweet

  I've recently been appointed to create some VMs for production use, and went gung ho into making a KVM based VM instead of finding out what our production server uses. I've only recently found out though that our own servers use Xensource OS, and don't look like they're going to be upgraded in the near future. So for the moment, I'm stuck with either two choices- attempting to convert the KVM VM into a Xen VM, or rebuilding what I have into a new Xen VM. Being the lazy person I am, I would rather not have to rebuild the VM. I've looked for some documentation on a procedure to do this, but the only thing I can come up with is an ancient article with some vague instructions. So this is my question, Server Fault- can one migrate a KVM running on a KVM kernel to a Xen kernel? And if so, how?

  Read the article

• Help deciding on language for a complex desktop - web application

  - by user967834

  I'm about to start working on a fairly complex project needing a desktop GUI as well as a web interface and I need to decide on a language(s) to use. This is from an electrical engineering/robotics background. These are the requirements: Program will have to read data from multiple sensors and inputs (motion sensor, temperature sensor, capacitive sensor, infrared, magnetic sensors, etc) through a port on a computer - so either through USB or ethernet. Program will have to be able to send control signals based on this input. Program will have to continuously monitor all input signals at all times - so realtime data. Program will require authentication. Program will need to be controllable from a web interface from anywhere via logging in to a website. Web interface will also need to have realtime feedback once authenticated. What language do you think would best accomplish this? I was thinking maybe saving everything into a database which can be accessed by both the desktop and web app? And would Python be able to do all of this? Or something like a remote desktop app? I know this is a complex project but let's assume I can learn any language. Has anyone done something like this and if so how did you accomplish it?

  Read the article

• Why it is called "hash table", or "hash function"? Hash doesn't make any sense to me here

  - by Saeed Neamati

  It's now about 4 years of development that I'm using, hearing, talking about, and implementing hash tables and hash functions. But I really never understand why it's called hash? I remember the first days I started programming, this term was kind'of cumbersome terminology to me. I never figured out what is it, based on its name. I just experimentally understood what it does and why and when should we use it. However, I still sometimes try to figure out why it's called hash. I have no problem with table or function and to be honest, they are pretty deductive, rational terms. However, I think better words could be used instead of hash, like key, or uniqueness. Don't key table or uniqueness table. According to my dictionary, hash means: Fried dish of potato and meats (highly irrelevant) # symbol (AKA number sign, pound sign, etc.) (still irrelevant, maybe just a mis-nomenclature) Apply algorithm to character string (still has nothing to do with uniqueness, which is the most important feature of a hash table) Cut food Another term for hashish Does anyone know why it's called hash?

  Read the article

• I need an approach to the problem of preventing inserting duplicate records into the database

  - by Maurice

  Apologies is this question is asked on the incorrect "stack" A webservice that I call returns a list of data. The data from the webservice is updated periodically, so a call to the webservice done in one hour could return the same data as a call done in an hour. Also, the data is returned based on a start and end date. We have multiple users that can run the webservice search, and duplicate data is most likely to be returned (especially for historical data). However I don't want to insert this duplicate data in the database. I've created a db table in which the data is stored (most important columns are) Id int autoincrement PK Date date not null --The date to which the data set belongs. LastUpdate date not null --The date the data set was last updated. UserName varchar(50) --The name of the user doing the search. I use sql server 2008 express with c# 4.0 and visual studio 2010. Entity Framework is used as the ORM. If stored procedures could be avoided in the proposed solution, then that will be a plus. Another way of looking interpreting what I'm asking a solution for is as follows: I have a million unique records in my table. A user does a new search. The search results from the user contains around 300k of the data that is already in the db. An efficient solution to finding an inserting only the unique records is needed.

  Read the article

• Layout Columns - Equal Height

  - by Kyle

  I remember first starting out using tables for layouts and learned that I should not be doing that. I am working on a new site and can not seem to do equal height columns without using tables. Here is an example of the attempt with div tags. <div class="row"> <div class="column">column1</div> <div class="column">column2</div> <div class="column">column3</div> <div style="clear:both"></div> </div> Now what I tried with that was doing making columns float left and setting their widths to 33% which works fine, I use the clear:both div so that the row would be the size of the biggest column, but the columns will be different sizes based on how much content they have. I have found many fixes which mostly involve css hacks and just making it look like its right but that's not what I want. I thought of just doing it in javascript but then it would look different for those who choose to disable their javascript. The only true way of doing it that I can think of is using tables since the cells all have equal heights in the same row. But I know its bad to use tables. After searching forever I than came across this: http://intangiblestyle.com/lab/equal-height-columns-with-css/ What it seems to do is exactly the same as tables since its just setting its display exactly like tables. Would using that be just as bad as using tables? I honestly can't find anything else that I could do. edit @Su' I have looked into "faux columns" and do not think that is what I want. I think I would be able to implement better designs for my site using the display:table method. I posted this question because I just wasn't sure if I should since I have always heard its bad using tables in website layouts.

  Read the article

• Do you tend to write your own name or your company name in your code?

  - by Connell Watkins

  I've been working on various projects at home and at work, and over the years I've developed two main APIs that I use in almost all AJAX based websites. I've compiled both of these into DLLs and called the namespaces Connell.Database and Connell.Json. My boss recently saw these namespaces in a software documentation for a project for the company and said I shouldn't be using my own name in the code. (But it's my code!) One thing to bear in mind is that we're not a software company. We're an IT support company, and I'm the only full-time software developer here, so there's not really any procedures on how we should write software in the company. Another thing to bear in mind is that I do intend on one day releasing these DLLs as open-source projects. How do other developers group their namespaces within their company? Does anyone use the same class libraries in personal and in work projects? Also does this work the other way round? If I write a class library entirely at work, who owns that code? If I've seen the library through from start to finish, designed it and programmed it. Can I use that for another project at home? Thanks, Update I've spoken to my boss about this issue and he agrees that they're my objects and he's fine for me to open-source them. Before this conversation I started changing the objects anyway, which was actually quite productive and the code now suits this specific project more-so than it did previously. But thank you to everyone involved for a very interesting debate. I hope all this text isn't wasted and someone learns from it. I certainly did. Cheers,

  Read the article

• Time Machine (archive) of pre-Leopard systems?

  - by benc

  I want to get off an older Mac OS X system permanently. It is an iBook G3, so that has two important characteristics: Power PC, not Intel based. Runs only Tiger, not Leopard. This means, as far as I can tell: Cannot run Time Machine directly. Here's the approach I have been contemplating: Mount the drive in Firewire mode. Back up the drive as a external drive to the Time Machine volume. Disconnect the drive (permanently). However, I'm concerned that this drive will eventually age out, when the Time Machine volume fills up, and the old-system-as-external-drive is gone. Would it be better to do a single backup with another utility, to shared disk?

  Read the article

• On Screen Coin Animation

  - by Siddharth

  am working with side scrolling skater game. I want to perform coin animation such that as player collect coin it moves upside and attach with currency sprite. My main character and coin present in game scene and currency sprite present in HUD layer. This situation creates problem for me. Directly I can not apply modifier to coin because it is side scrolling game so based on main character speed it reaches at different position. That I have checked. So that I have to generate other coin at same position at game layer coin has, in HUD layer and move upward to it. But I didn't able to get its y position correct though I can able to get x position correctly. Many time main character goes downward so it get minus value many time. I also tried following code float[] position = GameHUD.this .convertSceneCoordinatesToLocalCoordinates(GameManager .getInstance().getCoinX(), GameManager.getInstance() .getCoinY()); But I am getting same coordinate as I provide. No difference in that so please some one provide me guidance in that. Because I am near to complete my game. EDIT: Here game layer and hud layer is totally different. Actual coin present in game layer which player has to collect and at same position I want to generate another coin in hud layer to perform some animation. It is recommended to generate coin in hud layer because through that only I can able to complete my target.

  Read the article

• How do I get a new column from a Sharepoint list into Excel?

  - by Jono

  I've been using Excel to process data from a Sharepoint list for a while now. However, I recently added a column to the Sharepoint table, and when I refresh the data in Excel, I don't get the new column. I perform a lot of calculations based on this data, so creating a new worksheet with the "new" Sharepoint list, moving the calculations and the pivots to THAT sheet is more hassle than I'd like to face. Is there a way to force Excel to display this new column that I've added? Maybe by modifying the connection string?

  Read the article

< Previous Page | 596 597 598 599 600 601 602 603 604 605 606 607  | Next Page >