Wikipedia:Reference desk/Archives/Computing/2010 September 14

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September 14

Lost pictures on SD card

I have recently loaded pictures on my PC from my SD card . Now my SD card says no image when in the camera how do I return the pictures to my SD card from the PC? Alan Wright —Preceding unsigned comment added by 213.7.151.47 (talk) 05:57, 14 September 2010 (UTC)

Did you perhaps move rather than copy? Sometimes you can just copy back again, but sometimes this doesn't work in the camera. There is software available that will recover lost images. I recently used Convar's "PC Inspector smart recovery" and was surprised to find images from more than a year ago still on the (large) SD card. Dbfirs 07:14, 14 September 2010 (UTC)

Question header added. AndrewWTaylor (talk) 07:44, 14 September 2010 (UTC)

Are you asking how to move photos from your computer to your camera? Many cameras will insist on having the exact files created by the camera with the exact file names, in the exact folders. If you've so much as rotated them by 90 degrees the camera may refuse to recognize them. (They're not really general-purpose image viewers.) So you'll need to take those exact files and copy them back into the exact same folder they were in. APL (talk) 15:16, 14 September 2010 (UTC)

In the event you didn't move them, but instead they were erased, there are ways to recover things from the SD card. But to do so, don't use the SD card until you've recovered the files you're interested in. If that's the case, ask it as a new question here. Shadowjams (talk) 01:21, 15 September 2010 (UTC)

If you need to recover files, what operating system are you using. Second, how do you access the files on your camera (do you remove the card and put it into the computer/another device, or do you plug a cord into your camera). Shadowjams (talk) 06:46, 15 September 2010 (UTC)

Shadowjams gives solid advice about not attempting to use the SD card till you've retrieved any content from it. Whether your OS is Windows (95 or above), Mac OS X or Linux, an excellent tool for retrieving content from the card is PhotoRec. (You'll find its price appealing too.) Tama1988 (talk) 07:43, 15 September 2010 (UTC)

I would say reading from the SD card probably wouldn't hurt, but writing to it is forbidden. On most file systems, deleting a file doesn't really delete it - all it does is remove its entry from the file allocation table, making the file system no longer able to find it and making it think it's free space, fresh for new files to use. A thorough scan of the medium itself will still find it, which is what programs like PhotoRec do. However, if you want to be on the safe side, then not even reading from the SD card before the retrieval operation won't hurt, it can only help things. JIP | Talk 12:13, 15 September 2010 (UTC)

Java generics, what use is "extends"?

Resolved

Java generics there are wild cards. I understand these as

• "?" - any type
• "? extends T" - any subtype of T
• "? super T" - any superype of T

I can see that "extends" could be useful, if you want a list of types extending a class or interfaces, but I can't grasp what use "super" is. Presumably "super T" means that objects or any other supertype can be assigned, so you really can't say much about the contents! -- Q Chris (talk) 08:08, 14 September 2010 (UTC)

Read about the "Get and Put Principle" here, and follow up in this thread if you still don't get it (this stuff is tricky!). Page 7 of this presentation has a shorter treatment. --Sean 14:50, 14 September 2010 (UTC)

Covariance and contravariance (computer science) is the Wikipedia article about this, though it could stand improvement. The idea is simply that you can convert from a subtype to a supertype, but not the other way around. So if you're storing a value into an array of T, for example, you can use any subtype of T, while if you're loading a value from an array of T, you can treat it as any supertype of T. If you're both loading and storing then it needs to be both a subtype and a supertype of T, and the only type with that property is T itself. This ought to apply to Java's built-in arrays too; the fact that it doesn't is a famous hole in Java's type system, mentioned in the article. -- BenRG (talk) 18:57, 14 September 2010 (UTC)

Thanks both of you, I see it now! -- Q Chris (talk) 10:28, 15 September 2010 (UTC)

can we make an arrangement?

Is it probable I can make an arrangement with someone with much greater programming skills than myself, as well as money from their programming career, but with a dearth of ideas, such that I - for whom the implementation of any of my ideas would take a month of solid programming investment - could supply them the idea and direct their programming activity but we could jointly share from the profit? (Even if at a rate of 10% for myself). Or is that arrangement less than probable? If it is probable that I could make it, where should I start? 92.230.233.251 (talk) 12:49, 14 September 2010 (UTC)

Bluntly:

1. Everyone has ideas. I get so afflicted by ideas that I write them down so I can get peace to get on with what I was doing; so I have a pile of ideas twice as thick as the phone book. There's all kinds of junk: spine-crushingly wonky space elevators, video games of immense complexity and unutterable dullness, parallel computation using brittlestars, weird tensegrity structures, and the plot for an adult movie so filthy it would set the sky on fire. I don't claim to be imaginative; I'm probably rather below average. When everyone has ideas, ideas alone are worthless.
2. People who don't program vastly underestimate how much programming effort anything worthwhile takes. This is exacerbated when they see how relatively quickly a decent programmer can knock out something that looks finished (a half-decent web programmer could put out a Twitter clone in a few days; that doesn't remotely mean that there's a few days, or even a few years, of programming in Twitter)

So, frankly, if all you bring to the table is an idea, you bring nothing.

Unfortunately, I look like I'm a nice approachable decent human being (when I'm nothing of the sort) and remarkably frequently people make me just the proposition you're suggesting. Their "idea" is mostly along the lines of "Facebook but better", "Twitter but better", "Google but better", and so forth. These people have neither an idea nor a clue.

That said, there are plenty of circumstances where a non-technical person is key in building a business based on a technical system like a website. But that person has to bring a great deal to the table: a fully explored design of what needs to be built (literally hundreds of pages of detailed design), graphic design, marketing strategy, business plans, customer lists, financial models, in-depth lists of prospective customers, and well developed relationships with customers, suppliers, partners, and investors. With all that in place, when the software is just a component, when you've got the business kinda running with a paper-based system or some Excel macros cobbled together, then you're certainly in a position to build a business. I'm sorry if I sound blunt or discouraging: there are huge opportunities for people to build interesting businesses and exciting systems, and millions of people struggling with mostly-manual business processes, but the road to Damascus is a long one, and the idea is just the first of very many steps. -- Finlay McWalter ☻ Talk 13:41, 14 September 2010 (UTC)

This is how it is stated in the entertainment industry: Ideas are worthless. Money is in execution. -- kainaw™ 13:42, 14 September 2010 (UTC)

Post one of your ideas here and perhaps one of the many programmers on this forum will comment on it to give you an idea of how realistic your plan is. --Sean 14:56, 14 September 2010 (UTC)

That's just the problem (beyond what Finlay already said). There's no legal protection for ideas, so a person wanting to make money from it won't be willing to post it to find out its value. Moreover, they can't trust a random programmer they've just met not to say "wow that's crap" and then go home and write/sell it. You'd have to have a contract (almost an NDA) before starting such an endeavor, and most programmers aren't going to want to sign a contract just to hear some idea of completely unknown value to them. You'd probably have to pay them to sign the contract and listen! --Tardis (talk) 14:58, 14 September 2010 (UTC)

Unfortunately, because of everything outlined by Finlay, even if your idea is one-of-a-kind brilliant and actually possible, programmers are going to be very, very wary of working under the terms you outlined.

Though 90% of the profits is very reasonable, but who is going to market it and make it a big success? (For example : Run-away hit Farmville is a clone of an earlier web game that no one had heard of.) It seems like you're expecting a lot of profits, who will be handling the business side of things? Who will be managing everything? Is your idea web-based? If so, who will handle the maintenance costs that will sky-rocket once your idea becomes popular? (And who will actually perform the maintenance? If the answer to this question starts "Well, you're our technical guy..." the programmer will head for the hills.)

I'm not saying that a two-man team couldn't take the world by storm, but your half of the team is going to have to have a lot more on the ball than "idea man". APL (talk) 15:13, 14 September 2010 (UTC)

OP here. You can't have it both ways, guys. If I were to understand and agree with your reasons for not going into the arrangement I outlined, I would immediately cease to have an ounce of sympathy for someone working for a mere $40-$60 per hour while their boss makes millions off of them. In fact, if a decent programmer can implement my ideas in a couple of hours, by everything I've just read above, I should just pay them for their time on an hourly rate, without sharing a cent of my profits. Well, enjoy your $600, mates. 82.113.121.135 (talk) —Preceding undated comment added 15:27, 14 September 2010 (UTC).

In 99% of all cases would much rather work for hourly money upfront than for some vague promise of riches later. It's not worth it for me to buy into the delusions of grandeur of the world's approximately one zillion self-appointed "idea people".

Perhaps if you were a close friend and we had worked on the idea together, But otherwise if I'm going to spend "a month" working on some crazy idea, I'll just work on one of my crazy ideas and keep 100% of the money instead of giving 10% to you. Why wouldn't I do that? APL (talk) 16:04, 14 September 2010 (UTC)

To clarify : I place zero value on your idea (I can use my own for free), so what else do you have to offer?

If I'm going to take the plunge and spend "one month" (heh) working on a crazy, but potentially profitable, idea, I've got at least a dozen of my own I want to try before I pay out 10% to an "idea man".

If all you've got is an "idea" you're bringing coals to Newcastle. APL (talk) 16:16, 14 September 2010 (UTC)

Nonono, it would only take me (OP) a month. It would take you a couple of hours, since you already have enough background. Look, why don't you give me your phone number and I'll tell you ten specific implementations any single one of which would take a couple of minutes (in Perl) or a couple of hours (properly done) then you can quote me an hourly figure or a percentage, and I can decide if I want to go into it, and if so which one. For you it's win-win. 82.113.121.135 (talk) 16:41, 14 September 2010 (UTC)

Why not use a freelance programmer site like Elance? Then you can pay them in rupees or rubles and really come out ahead. --Sean 16:49, 14 September 2010 (UTC)

Also: I'm an expert-level Perl programmer with 15+ years experience in the language. I accept your proposed rate of $60 per hour. Make a confirmed $60 donation to the Wikimedia Foundation, and I'll spend an hour working on your proposal. After that, we can go from there, with all payment going to WF, if we both choose to proceed. Mail me at this spam-proof address: M8R-7y2sr11@mailinator.com . I promise not to steal your idea. --Sean 17:00, 14 September 2010 (UTC)

(ec) If the general public is going to interact with it, it will take a while to implement well. I worked on a project with a friend once that had two main components: a complicated machine learning system and simple web frontend (like a web forum but without discussion threads because we didn't know how we wanted them to work). Both pieces took a while to build, but the web frontend took significantly longer. The difference between a proof-of-concept and something that you can actually put online without embarrassment (or terrible security flaws) is a huge amount of plumbing. (I was quite proud how few lines of code the result wound up being. I had to write and then delete a whole lot to get there, though.) Paul (Stansifer) 17:10, 14 September 2010 (UTC)

Yep, not to mention the enormous amount of bikeshedding that occurs when you're doing non-technical things like choosing whether to round your corners. --Sean 17:36, 14 September 2010 (UTC)

The bikeshedding might not be so huge in a two-person start-up. APL (talk) 18:33, 14 September 2010 (UTC)

Ah, I misunderstood slightly, if we're really only talking about a day or so of work, your prospects look a lot better.

You're far more likely either find someone who will work cheap or who will say "what the heck" and go with it.

I notice that sometimes people advertise odd jobs for programmers on Craigslist. I have no idea if that actually works, but if you don't find someone it might be worth a shot. APL (talk) 18:33, 14 September 2010 (UTC)

OP, can we make an arrangement? I have this fantastic software that I have written 10 years ago. Once I go public with it it will revolutionise the software market. Microsoft will be toast – unless they learn about it too early. Which is why I have to be a bit secretive. Unfortunately, keeping my software up to date until I find a suitable distribution partner is getting a bit tiresome. I am looking for someone who has a reasonable amount of funds of their own and is also good at marketing and capital-raising. There is big money in this, but you will have to trust me, and obviously you can't expect immediate returns.

This is your chance! Are you game? Just write me an email with details of your financial and marketing background. If you appear like a suitable partner, I will tell you the approximate category into which my software falls and will give you further instructions for the first year or so of our partnership. If all goes well, we will be on the market in two to three years, and I promise you that at that point you will be extremely excited when you find out what my software really does! Hans Adler 17:55, 14 September 2010 (UTC)

if you really think Microsoft would be toast just because another solution is better, you do need help! :) 82.113.121.135 (talk) 18:07, 14 September 2010 (UTC)

"If the deal goes ahead there will be some good money in it for you." (link has bad words in it, so possibly NSFW.) Comet Tuttle (talk) 18:33, 14 September 2010 (UTC)

---

Attn: Original Poster

   I notice that while you are seeking to create a business arrangement with someone on the RefDesk, you have not provided even your name, which causes me IMHO to suspect that you may be a Scibaby sockpuppet. In addition, you have failed to state what kind of work you need done; website design, website programming, web application development, etc. I am a Website Designer, and I can design just about anything in HTML, CSS and ECMA-262. If you are for real and this is the kind of work which you need, I propose that you make a confirmed US$50 donation to the Wikimedia Foundation, and for that I will work on your project for an hour. Thereafter, if you wish to retain me (with all proceeds going to the Wikimedia Foundation), we can discuss rates and proceed from there. Click here to contact me via email, or leave a message on my talk page.Vickreman.Chettiar 21:08, 14 September 2010 (UTC)

Which torrent client allows establishing without too much effort exlusive connection to one peer only

I have a .torrent file with thousands of seeds. I also happen to know the exact IP and port of a certain seed with an unusually high upload ability (it was set up unofficially by my Internet provider to reduce the load on their side for popular torrents). I am actually able to establish an exlusive connection to this peer, but it requires a lot of effort in my uTorrent client (I do it by restarting the torrent download a number of times and then quickly reducing the number of allowed peer slots to one, and it's very frustrating). Does somebody know of an easier way? —Preceding unsigned comment added by 93.172.63.16 (talk) 14:04, 14 September 2010 (UTC)

uTorrent lets you block IP address ranges; you should be able to tell it to block 0.0.0.0-1.2.3.3 and 1.2.3.5-255.255.255.255, after which it will only connect to 1.2.3.4. I've never tried it, though. -- BenRG (talk) 19:01, 14 September 2010 (UTC)

Thank you, it works! Added 2 lines to ipfilter.dat then "Reload IPFilter" and bingo. Nice trick 93.172.63.16 (talk) 22:52, 14 September 2010 (UTC)

Is it just me or should OP be very sceptical to an ISP that does this? While this sort of service is nice, it seems to me that to pull this of they need to analyse throughput of their routers to an extent that are a serious privacy concern. Taemyr (talk) 23:18, 14 September 2010 (UTC)

If the torrents in question are at all illegal, I would assume it was a honeypot and avoid it like the plague. APL (talk) 02:03, 15 September 2010 (UTC)

In NZ my ISP, and I think a number of other ISPs do this. My ISP uses Oversi [1] I believe. PeerApp is another popular caching solution. These may work by themselves of may work with things like Blue Coat (see [2] for example) who themselves may offer a stand alone solution. Huawei have something as well it seems [3].

I would expect the situation is similar in Australia. And likely other countries where international bandwidth is an issue (although not Malaysia AFAIK). The IP looks up to Israel and while I don't know what the situation is like in Israel several of the things I found during my searches seemed to mention Israel so it wouldn't surprise me if caching is used there a lot.

With my ISP you ask them to turn off the caching completely for your connection (a setting in your account online), which will cut off all caching including transparent web proxy (also something extremely common here) and Youtube caching. Also last I was aware, the caching won't work with Bittorent encryption, so you have to at least not require it for it to work. (I think making it not use encryption by default is recommended.)

Either way, during major peak times and since my ISP has a free overpeak period during most of the free offpeak period, the speed tends to be rather slow outside of the caching. (Encryption and UTP don't help much AFAIK.) Well a local high speed seed would probably be fairly fast but as the vast majority of broadband connections are ADSL/2+ or things likely to be even slower like wireless and most people have data caps and/or pay for data (the cheapest rate usually being NZ$1/GB or higher) you don't tend to get that many local high speed seeds.

I've never actually had the need to only download from the cache, it seems to work fine enough to me without doing that. (Of course many things are not cached, particularly since I often don't go by what's most popular and do often only end up downloading stuff after it's been out for quite a while.)

This isn't legal advice but in NZ, at the current time most ISPs won't do anything without a court order. One ISP will forward any complaints received to customers and cut them offer after a certain number of complaints. There were plans to require this (disconnections) in law, but it was semi-abandoned after an outcry. There is current a revised bill which will still require disconnections but is supposed to make it more difficult, the revised bill is still in the select committee stage I believe [4].

Nil Einne (talk) 18:50, 15 September 2010 (UTC)

Map Building

I need a program that lets me label certain locations on a given map. Is there a program or online resource that I can give the postcodes (zip codes) and names of some places and it will superimpose them onto a map? Even just a point and click selection would be fine! — Fly by Night (talk) 16:31, 14 September 2010 (UTC)

Google maps does that. Go to http://maps.google.com and click on My Maps. Then, you can place icons, labels, and anything else you like on the map. You can save the map and others can open it through the URL provided. -- kainaw™ 16:55, 14 September 2010 (UTC)

Google Earth has this capability as well. --Mr.98 (talk) 00:38, 15 September 2010 (UTC)

Before Google did it, Microsoft MapPoint did basically that; but I found it kind of unwieldy and tempermental at times. Kingsfold (Quack quack!) 18:27, 15 September 2010 (UTC)

Fios

what is Fios internet —Preceding unsigned comment added by Kj650 (talk • contribs) 22:21, 14 September 2010 (UTC)

Check out Verizon FiOS. Basically it's a high speed internet connection delivered over fiber-optic cables.

APL (talk) 22:23, 14 September 2010 (UTC)

(ec)Judging by Verizon FiOS it's the use of fibre-optic cables to the home ... or somewhere near the home. See Fiber to the x and the first paragraph in the Verizon article. Fibre has more carrying capacity - greater bandwidth - than cable or DSL. I presume there are implicit or explicit promises of high speed services with such things as Verizon FiOS. --Tagishsimon (talk) 22:25, 14 September 2010 (UTC)

do they have to run new line INSIDE my house? how complicated is it? —Preceding unsigned comment added by Kj650 (talk • contribs) 23:31, 14 September 2010 (UTC)

yes. -- Finlay McWalter ☻ Talk 23:35, 14 September 2010 (UTC)

that link tells me nothing —Preceding unsigned comment added by Kj650 (talk • contribs) 00:09, 15 September 2010 (UTC)

Are you using a recent browser? If you give it a second or two to load, and then scroll down, there's information about the tech coming out to install an optical network terminal in your garage, etc. Comet Tuttle (talk) 00:20, 15 September 2010 (UTC)

i said INSIDE my house —Preceding unsigned comment added by Kj650 (talk • contribs) 00:46, 15 September 2010 (UTC)

Calm down and please read the link Finlay supplied. It clearly states "At your home, we’ll install a small box called an ONT (Optical Network Terminal) in your garage, basement or other inconspicuous place, or near your telephone box outside. Inside, we’ll setup a router and any necessary wiring and wall jacks" (emphasis added). If you need more info, hatever you need to know; or there are plenty of other contact options here. Astronaut (talk) 01:48, 15 September 2010 (UTC)

that dosent help. i want your experiences with installation for fios

"FiOS" by itself refers to all three of Verizon's fiber-optic services: FiOS phone, FiOS internet, and FiOS TV. The page mentioned above estimates the install will take 4 hours or more, the complexity of the installation probably depends on which one or more of the three services you order, and if your home has existing phone and coax wiring that is suitable.

The fiber goes to the ONT, which may be installed outside or inside, but usually on a perimeter wall. (In apartments, some areas will have one ONT per building, some areas will have one ONT per household.) The ONT connects to the phone, coax, or in some cases Ethernet wiring in your home, and converts the incoming light signals on the fiber cable into electrical signals on the wiring in your home. If your home has existing phone and coax wiring, the installation technician will likely use it. If needed, the technician will install appropriate wiring and jacks. But the wiring in your home will be phone or coax wiring. The fiber only goes as far as the ONT, which will be outside or close to outside, so the fiber actually in your home will be none or minimal, but it will go right up to your home.

The ONT connects to electrical power and a battery backup unit, which is always inside. If that electrical outlet goes out or gets unplugged, the battery will provide power to the ONT, but after about 5 minutes, the ONT will shut off internet and TV signals and only power the phone signal to conserve battery power. (If the electricity is out in the entire house, you won't be able to use cordless phones, but regular corded phones will work.)

More links: --- a ZDNet photo gallery of a FiOS installation --- Broadband Reports' Verizon Online FiOS FAQ: Installation --- FiOS users discuss installation questions. --70.253.38.181 (talk) 05:08, 15 September 2010 (UTC)

You're being rude. Please be less rude. --Sean 14:42, 15 September 2010 (UTC)