Wikipedia:Reference desk/Archives/Computing/2010 October 12

= October 12 =

Wanted: Offline Windows Live Installer Wave 2, English
Does anyone have it?

It was located at http://g.live.com/1rewlive/en/WLSetup.exe, which redirects to http://download.microsoft.com/download/3/6/e/36e9a77e-6eee-4b8c-b223-5d8b5b4e2a28/EN/WLSetup.exe. Unfortunately, the file has been taken down.

P.S. This is for my personal collection, so no newer versions and online installers, please.

118.96.161.28 (talk) 00:01, 12 October 2010 (UTC)

User Account
Hi There,

My user name is HappyGod. Recently I changed my password, and I am no longer able to login.

Please note that I am certain of my password, and have not forgotten it. I think you may have bugs in your change password functionality.

Anyhow, could I suggest that you include a "Forgot your password" option on the login page? In the meantime, could you please advise as to how I can regain access to my account?

Regards, Matt Vermeulen —Preceding unsigned comment added by 203.161.88.182 (talk) 08:11, 12 October 2010 (UTC)
 * For Wikipedia, you must go to the Help Desk and ask there. However, I think there is no way you can get it back, unless a bureaucrat does it... And yes, you can also suggest a Forgot your password at the Help desk as well. The help desk can be accessed by going to the top of the page and clicking on the link on the right hand side of this page. Sir Stupidity (talk) 08:24, 12 October 2010 (UTC)
 * There is already a facility for forgotten passwords on the login page:
 * "If you entered your e-mail address when you signed up, you can have a new password generated. Click on the "Log in" link in the upper-right corner. Enter your user name, and click the button near the bottom of the page called "Mail me a new password". You should receive an e-mail message with a new random password; you can use it to log in, go to your preferences, and change your password to something you'll remember.".
 * Unfortunately, if you have changed your e-mail address and forgotten to update your profile, then this will not work, so you might just have to create a new account, but if this is the case, then ask at the help desk, as advised above.   D b f i r s   09:28, 12 October 2010 (UTC)

Thumb drive security
I am using a U3 thumb drive and wish to minimise the impact if I lose it. So:

1. Is there a way to password protect individual files or folders on a thumb drive?

2. How can I easily backup/synchronise all files between two thumb drives (assuming all files are password protected)?

Also, I am looking for portable security software that I can install on thumb drives (antivirus software, virtual sandboxing, etc.). —Preceding unsigned comment added by 59.189.218.201 (talk) 08:17, 12 October 2010 (UTC)
 * TrueCrypt 82.44.55.25 (talk) 09:38, 13 October 2010 (UTC)
 * For hardware based encryption see Comparison_of_encrypted_external_drives and Ironkey.Smallman12q (talk) 13:04, 13 October 2010 (UTC)


 * I use TrueCrypt, too. I create an "encrypted file container" on the thumb drive of, say, 1GB, install TrueCrypt on all my machines, and then when I need the files from the thumb drive, I use TrueCrypt to mount the encrypted file container as my G: drive (or whatever).  There is one significant disadvantage to this:  If you take the thumb drive to a friend's house or a print shop or a client, then they also need TrueCrypt installed in order to get to any of the files.  (I keep the TrueCrypt installer, unencrypted, on that thumb drive, of course, to take care of those situations.)  Comet Tuttle (talk) 22:02, 13 October 2010 (UTC)
 * TrueCrypt can be run in portable mode directly from the usb drive 82.44.55.25 (talk) 22:16, 13 October 2010 (UTC)

Is there a way to burn a CD from Ubuntu Live
I am in the process of upgrading my Ubuntu OS to 10.10. I started installing and the installation failed with "unable to copy from CD". After some investigation I discovered that: I have now downloaded a new copy of the image and verified it (booting from Live CD). If I can burn this image then I can continue. The only problem is that I am running from the LiveCD and every attempt to remove the CD and enter a blank results in failure (the write-cd crashes). Is there a way round this or will I have to reinstall the previous version, write the CD, then install the new version again? -- Q Chris (talk) 11:12, 12 October 2010 (UTC)
 * My computer is now unbootable - I have already overwritten the system partition
 * The CD image I downloaded is incomplete (I know I should have done an md5sum before installing.


 * Rather than burn a CD/DVD, do you have a usb drive (a flash drive will do) from which your computer will boot? You should be able to make a bootable USB system with Ubuntu Live USB creator. -- Finlay McWalter ☻ Talk 11:16, 12 October 2010 (UTC)
 * A good idea but I'm afraid its an old laptop and the BIOS doesn't support booting from a flash drive. I have started reinstalling the previous version, but if anyone does know a way it might help other people save time. -- Q Chris (talk) 12:44, 12 October 2010 (UTC)
 * I have now gone through the process of reinstalling the old system, burning the CD then installing the new one. I will mark as resolved but if there is a "shortcut" other people might be interested. -- Q Chris (talk) 06:19, 13 October 2010 (UTC)

Game programming
How is a game like Doodle Jump likely programmed? Would the various platforms be given rules about where they can be placed, along with enemies, power-ups, etc. and then the game creates a new board for each new game played? This could provide an infinite number of maps. Or would the programmer put together maps, say maybe 100 or so, and the game picks one randomly at start up? Dismas |(talk) 12:59, 12 October 2010 (UTC)


 * If it's really infinite, like the article says, you'd use procedural generation to build content, based on pre-defined rules. If it's for something vital like the playfield itself (rather than textures, terrain, sound etc.), where a defect could cause an unwinnable scenario, you'd either use a set of generator rules that you could show were guaranteed to produce a winnable game, or you'd write a little analyser than checked a generated map to verify that it was winnable.  A decent generator should be tunable to allow for a difficulty gradient: as the game progresses, magic swords get fewer, lava streams wider, and giant aliens more frequent.  It can be a challenge to write generators that produce game content that, at the higher reaches, still feels credible. -- Finlay McWalter ☻ Talk 13:31, 12 October 2010 (UTC)


 * Or "procedural generation with hacky fudging". A friend of mine wrote a Oblivion-like adventure game, with fractally-generated terrain. But sometimes the randomly generated locations for things was such that you just couldn't walk from A to B. So he wrote a thing that detected this, and blurred the map over a wobbly pattern between A and B (like a giant finger that had descended from the sky, squishing the offending obstacle). It mostly worked okay, but if you knew what to look for, you could stand on a mountain top and see where A or B might be, as the fingerprint of the giant finger was a bit too visible. -- Finlay McWalter ☻ Talk 13:54, 12 October 2010 (UTC)


 * Interesting. Thanks!  Dismas |(talk) 23:11, 12 October 2010 (UTC)


 * Actually (as of whatever the last version was that wasn't codesigned, and therefore was source-readable to some degree, and I doubt the game has undergone a major overhaul since then), it's not generated according to a set of "rules". In the source, there was a whole section of XML files for various difficulties (about 35 per difficulty level, I believe) that defined exact placement of articles. The main game engine then picked a random XML file and stacked it on top of the existing map whenever it needed to; so in that sense it was "infinite", but not random.
 * (also, the fact that it was XML and not compiled code made it easy to "hack" or mod, so that you could just put auto-rockets everywhere. If you look in the highscores, you'll see some people with absolutely ridiculously high scores. OpenFeint doesn't check for the game version, just the game, so people would revert to old versions, mod, and use that score for OpenFeint.) [&#65279;flaminglawyer] 23:54, 14 October 2010 (UTC)

price/performance sweet spots for a Tower system.
What are some price/performance sweet spots for a Desktop system today? (I mean, perhaps you can get a really adequate desktop for office work for $50, and the next higher level gets you to an dual-core i5 with a graphics card that can run any modern game and has 4 GB of RAM, and this setup costs $275, and the next higher level you can get a quad-core i5 with 16 GB of RAM, an HD graphics card and 1 TB hard-drive and this setup costs $470, and the next higher level you can get a quad-core i7 with 64 GB of RAM and dual HD-graphics cards that work together, and 2 TB storage plus 256 GB solid-state storage, and this setup costs you $1300...) I am looking for the very best sweet spots YOU could assemble (with new-egg components). What are these systems, and these price-points? Thank you. 84.153.253.103 (talk) 16:41, 12 October 2010 (UTC)
 * This is probably not really a "reference" request. You might find a website like Tom's Hardware helpful for evaluating and comparing hardware performance; you already know about newegg... Nimur (talk) 16:54, 12 October 2010 (UTC)
 * This article I read last month was useful, but I don't necessarily agree with all of their choices. Check Tom's Hardware for more in-depth analysis. Coreycubed (talk) 20:20, 12 October 2010 (UTC)

When you buy a domain name separate from hosting
Do you tie the domain to your web server's IP address via a dashboard with the domain name vendor site or some other way? Thanks. 20.137.18.50 (talk) 19:46, 12 October 2010 (UTC)
 * Yes, assuming you were also using their nameservers, you'd use whatever DNS manager they have to set the A records (or any other DNS records) to your existing IP address. If you are just buying the domain from them, you can even point to another nameserver in many cases if you desire. Coreycubed (talk) 20:08, 12 October 2010 (UTC)


 * Let's say, for an example, you registered "snorkspork.com". The registrar has to fill out the NS record, which goes to the root domain name system servers.  That way, if anyone wants to know the actual IP address of chat.snorkspork.com, they ask their DNS server (which in turn asks a root server) for the NS record for snorkspork.com.  That gives two addresses (a main and a backup) for name servers you control. They then ask one of those for the specific address for chat.snorkspork.com; that's probably a trivial question for a personal or small business domain, but it's a big deal for a large outfit like google, where there are hundreds of xyz.google.com machines, and google's public-facing name server has to tell visitors which one to send their traffic to.  When you buy web hosting package (say from Rackspace or Dreamhost or whomever) you get that name server as part of the deal. All that remains is for the public NS record for snorkspork.com to point to the name server at (say) Rackspace that knows about your account.  How that comes to be, and how it gets changed, depends a bit on your setup.  If you register a new domain, the registrar will ask you for those two name server IPs; most registrars have a dashboard that lets you change these.  Alternatively your hosting company can change them on your behalf. Obviously if anyone could change the name servers for anything, it would be trivial to maliciously redirect the traffic from (say) google.com to hotnakedfatblokes.com, which would be bad. So changes to the NS record by third parties are often marked as "CLIENT TRANSFER PROHIBITED" (you'll see this in whois records a lot). Extensible Provisioning Protocol describes the framework under which different entities (hosting companies and registrars, mainly) interact, and this might also help. -- Finlay McWalter ☻ Talk 20:08, 12 October 2010 (UTC)

A beginner's language for databases or business?
I like the idea of databases as Attribute-value systems or the Entity-attribute-value model. Are there any beginner's languages that I could write and manipulate such a database with?

On a slightly different topic, are there any beginers languages that are suited to writing business rules and procedures with? An important feature would be date and financial functions, and firing off responces when stated conditions are met. Or is COBOL still the one to use? I do not want to use a spreadsheet. Thanks 92.15.31.184 (talk) 20:02, 12 October 2010 (UTC)


 * If you do not want a full relational database, you might find Java Properties useful. These are simple attribute=value mappings (key-value pairs).  The Java programming language has the advantage that it is widely used, is easy to learn, and will allow you to migrate to more elaborate database schemes (including relational databases) if you ever need to.  According to many surveys, Java is the most widely used business programming language (or at least in the top 2 or 3).  Nimur (talk) 20:20, 12 October 2010 (UTC)

That is way too complicated for me, and requires a lot of prior knowledge which I do not have. I'm looking for something suitable for a beginner, for occasional use. 92.15.31.184 (talk) 20:36, 12 October 2010 (UTC)


 * For a complete beginner, there is no reason that you cannot use Access. It is a front-end and database all in one.  It is limited in functionality, but can do most things that people want to do.  It is even used for full business applications.  I've seen it used for inventory systems, cash register systems, and laboratory studies. --  k a i n a w &trade; 21:43, 12 October 2010 (UTC)

Thanks, but I cannot use Access as I deleted Microsoft Office from my HD long ago, and I intend to migrate to Ubuntu in the future.

Perhaps I can try another tack: would it be easy to write an AV or EAV database in BASIC or some other simple language? Thanks again. 92.15.31.184 (talk) 22:03, 12 October 2010 (UTC)
 * How about OpenOffice.org Base ? It is similar to Access in features and interface, but is entirely free software.  Nimur (talk) 22:08, 12 October 2010 (UTC)
 * Any modern scripting language should be possible. I happen to like Python. It has data structures that support attribute/value pairs (dicts), and indeed the whole language is implemented around that design, although that is not visible at the first glance. --Stephan Schulz (talk) 22:12, 12 October 2010 (UTC)


 * If you're intending to do some simple programming, you'll find most modern programming languages essentially implement an attribute-value system straight out of the box, either as an array or as an associative array. For an array, you refer to each record by number (e.g. "retrieve record # 4"); for an associative array you refer to each record by something like a name (e.g. "retrieve record 'jenny'"). A modern BASIC implementation like FreeBASIC can (apparently) do this; it's particularly easy to do (and pleasantly legible) in python. -- Finlay McWalter ☻ Talk 22:21, 12 October 2010 (UTC)