Wikipedia:Reference desk/Archives/Computing/2010 October 15

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October 15[edit]

Which one should i make? a facebook page,a wix website or wordpress[edit]

I want to have a space dedicated to facebook games,but right now i don't have that much money or the technical knowledge required to build a website, so i was thinking which one of the choices above should i choose to make my page\site.thank you —Preceding unsigned comment added by 76.79.129.50 (talk) 02:21, 15 October 2010 (UTC)[reply]

Wordpress is probably best, although if you're specifically looking for facebook games, a facebook group might be a better idea. Chase me ladies, I'm the Cavalry (talk) 13:43, 18 October 2010 (UTC)[reply]

PuTTY[edit]

Earlier today, I downloaded PuTTY and installed it (don't worry about malicious downloads; I got it from http://iuware.iu.edu, since I'm an Indiana University student) for use with a UNIX-related class. Two questions about the program:

  1. Why is it called "PuTTY" and not "Putty"? The article explains the etymology, but it doesn't address the capitalisation.
  2. I periodically clear my cache to get rid of extraneous temporary files. Does PuTTY have the ability to store anything that could be cached (i.e., or do I always need to remember everything that I put into it), or am I correct in guessing that it's a simple enough program that it's not able to do this? I know that clearing my cache won't affect things on the server that I'm accessing; my question refers to the way the program itself operates. I've used this program before, but only in computer labs, and never before on my own computer. Nyttend (talk) 03:16, 15 October 2010 (UTC)[reply]
The official PuTTY FAQ explains the etymology. In Unix, a TTY used to be a teletype device, but now tty in general refers to any terminal - hardware or software text input/output utility. It's been rumored that "PuTTY" was originally named "Plutonium TTY" (I recall this etymology from before it was on the FAQ page). For your second question, PuTTY can save sessions - see the documentation on saving configuration. "Saved sessions are stored in the Registry, at the location HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions." Nimur (talk) 04:16, 15 October 2010 (UTC)[reply]

VBA problem[edit]

In VBA, what is wrong with this code?

String("Forms![Merchant/PSP/Reseller/Sole Trader CCF]![txtCustomer Name]&" "& Forms![Merchant/PSP/Reseller/Sole Trader CCF]![txtCustomer Brand]")

Thanking you! —Preceding unsigned comment added by 81.142.17.250 (talk) 13:21, 15 October 2010 (UTC)[reply]

The String function just returns a multiple of a string. This one doesn't seem to specify how many multiples; it probably defaults to 1. The rest is just a concatenation of two strings with a space between them. (It looks to me like the syntax is wrong — there should not be quotation marks at the beginning or the end.) It looks like this was done in Microsoft Access, and it is saying that there is a form named "Merchant/PSP/Reseller/Sole Trader CCF", and on it there is a control named "txtCustomer Name" and one named "txtCustomer Brand". The final string will be the value of the "Name" field, plus a space, plus the value of the "Brand" field. (To reference fields in an access form, the syntax is Forms![FormName]![FieldName]) Make sense? --Mr.98 (talk) 13:48, 15 October 2010 (UTC)[reply]
Sorry, I misread it as "what is going on in this code." What's wrong with it is twofold: 1. String() is a function with two variables (number and string), 2. You have two too many quotation marks, 3. String is a function that returns a value but you don't seem to be returning anything.
If you are just trying to get the value of those two fields, you don't need to use String(). Just do something like this:
nameAndBrand$ = Forms![Merchant/PSP/Reseller/Sole Trader CCF]![txtCustomer Name]&" "& Forms![Merchant/PSP/Reseller/Sole Trader CCF]![txtCustomer Brand]
or...
Msgbox("The name and brand are: " & Forms![Merchant/PSP/Reseller/Sole Trader CCF]![txtCustomer Name]&" "& Forms![Merchant/PSP/Reseller/Sole Trader CCF]![txtCustomer Brand])
Make sense? Notice that I'm assigning the result to something (or putting it as an input to a function), and notice that I've removed the quotation marks at the beginning and end (which are inappropriate since you are referencing variables/objects and not literal strings). --Mr.98 (talk) 13:55, 15 October 2010 (UTC)[reply]

PC[edit]

PC means personal computer. Both Windows, Mac and Linux can be personal computers, can they not? So why then is PC used only for Windows? —Preceding unsigned comment added by 80.86.59.249 (talk) 13:50, 15 October 2010 (UTC)[reply]

Apple's marketing does not want to advertise "Windows", so they use "PC" when they refer to a Windows product. It also has the side-effect of setting Mac apart as being different than a personal computer. Nothing more than marketing semantics. -- kainaw 13:55, 15 October 2010 (UTC)[reply]
My understanding is that it comes from the old term IBM PC compatible, which designated a whole series of computers made by different manufacturers which nonetheless shared a common software compatibility. As an abbreviation, "PC" came to mean any computer hardware that could run DOS (later Windows). Now today this is a bit silly as a term since even Apple hardware can run Windows if you want it to, not to mention they are all personal computers in a literal sense, but such is how language and technology change or don't change. The general point that when you run Windows you often do so on totally different hardware (whereas you basically only run Mac OS on Apple hardware, though there are exceptions to that rule as well) is still valid, though calling it a "PC" at this point has moved the signifier pretty far from the referent. --Mr.98 (talk) 14:01, 15 October 2010 (UTC)[reply]
Somewhat supporting what others have said, while Apple likes to differentate themselves and use PC to refer to computers running Windows (a practice their more loyal 'fans' often follow), I'm not aware the *nix crowd does so (in fact many may encourage their fellow PC users running Windows to migrate to *nix and proudly tell people their PCs runs *nix), and I'm pretty sure there are quite a few vendors who sell things they call PCs with *nix preinstalled. Wintel used to be another favourite but it hasn't really worked so well since Apple moved to using Intel chips plus has always ignored the other x86 vendors. Nil Einne (talk) 15:56, 15 October 2010 (UTC)[reply]
The reason PC has stuck is that there's no other east way to make the reference. Apple controls both the hardware and software, so a macintosh personal computer can easily be referred to as a Mac. Windows refers to the software, which can run on a number of different machines made by different companies. so how do you refer to a Windows-running box? PC is easy, if inaccurate. --Ludwigs2 21:08, 15 October 2010 (UTC)[reply]
Although as I said, PC also usually refers to *nix boxes. If you're referring to a Windows specific PC, it's probably better then refer to a Windows PC, Windows computer or whatever. Nil Einne (talk) 08:21, 16 October 2010 (UTC)[reply]
Or perhaps WinPC? Nil Einne (talk) 15:31, 19 October 2010 (UTC)[reply]

Privacy settings: facebook status update[edit]

Hi, I've excluded some specific people from seeing one of my status updates on my wall, by using the "Custom privacy" function before i posted. How can i remove people from the "Hide this from"-list afterwards? I can't find out how to edit the privacy settings. Is there any other way, or do i have to post the status update once more? —Preceding unsigned comment added by 84.215.165.169 (talk) 14:29, 15 October 2010 (UTC) 84.215.165.169 (talk) 14:32, 15 October 2010 (UTC)Claudia[reply]

AFAIK you can't change the privacy settings after posting. Maybe as they work on improving their privacy they'll improve this in time to come. At this stage, I'd say it would be easiest just repost with the different settings. --jjron (talk) 02:55, 17 October 2010 (UTC)[reply]

what's the real use of the symbol on the key `[edit]

The symbol occasionally used for opening a single quotation `like this' (before closing it with a normal single-quote) looks really awkward in almost any font, and the symbol does not look at all as though it were intended for this use. So, if is not a genuine opening single-quote, what is it? (I'm talking about the tilde key without a shift, below the Esc key and next to the 1 on an American keyboard: ` or ~ depending on whether you're holding shift) 84.153.238.22 (talk) 17:22, 15 October 2010 (UTC)[reply]

We have an article `. Algebraist 17:24, 15 October 2010 (UTC)[reply]
Duh! I never thought I could have gotten the article without knowing the name of that symbol!!! :) 84.153.238.22 (talk) 17:25, 15 October 2010 (UTC)[reply]
Another grave problem solved. ;-) -- 78.43.71.155 (talk) 17:29, 15 October 2010 (UTC)[reply]
ah, yeah, that was very acute of you... --Ludwigs2 17:38, 15 October 2010 (UTC) [reply]
I'd say our answers have a certain ring to them, but since I am tooting my own horn with that statement, I hope you will let me off the hook for it. -- 78.43.71.155 (talk) 15:52, 16 October 2010 (UTC)[reply]
I've never seen a redirect like `.Vchimpanzee · talk · contributions · 19:24, 15 October 2010 (UTC)[reply]
Furthermore, there was a little square with the symbol below the hand when I clicked.Vchimpanzee · talk · contributions · 19:26, 15 October 2010 (UTC)[reply]
That is the expected behavior for all Wikipedia-internal links. Try it on your signature, or my IP - just hover the mouse pointer over it and hold still for a moment. -- 78.43.71.155 (talk) 10:51, 16 October 2010 (UTC)[reply]
Indeed. I also don't see why people are so surprised of the existance of the redirect. We try to make redirects for everything that is a likely search term and if trying to find out the name or info of a symbol, it's not that surprising you may search for it. The only cases when we won't have redirects would be cases where it hasn't been created yet or it we can't for technical reasons, like #. Nil Einne (talk) 16:29, 16 October 2010 (UTC)[reply]
The symbol is the grave accent, but the article doesn't explain why it's sometimes (mis)used as an opening single quotation mark. The reason: ASCII character 96 used to look like an opening single quotation mark in some computer fonts. For example, in the image at the top of code page 437, you can see it just to the left of the lower-case a. In modern times, if you see the grave accent used as an opening single quotation mark, it likely means there's some old ASCII conversion routines in place from when ASCII character 96 looked like an opening single quotation mark. --Bavi H (talk) 00:30, 16 October 2010 (UTC)[reply]
In fact, in the ASCII standard X3.4-1968, the character ` is named "grave accent (opening single quotation mark)", so as far as the US was concerned it was explicitly intended for both purposes. Similarly the ' was intended for three purposes: apostrophe, acute accent, and closing single quotation mark. This overloading was not generally copied in other standards that shared most of the same characters. So Bavi's wording "(mis)used" is exactly right. The discussion here may be of interest. --Anonymous, 03:38 UTC, October 16, 2010.
Besides the reasons given above, I often use it for find-and-replace when I need a character that doesn't exist anywhere on the pre-modification page — let's say that I'm trying to increase by 1 many different numbers in Notepad. I'll tell it to replace every occurrence of " 2" with "`3"; because the space before the number is taken up by the `, that new number won't be replaced when I order the program to change the 3s to 4s. As well, if I'm at a long page such as Template talk:Did you know, I'll normally search for my own username (to see what's going on related to the comments I've made), but since any single letter of my username has so many hits that it takes a long time to resume typing, I'll start with the ` character because it's not present anywhere, so the search function won't be delayed in trying to highlight all of the hundreds of relevant characters. Nyttend (talk) 23:01, 16 October 2010 (UTC)[reply]
The article linked above mentions this, but in LaTeX and maybe some other typesetting languages as well, ` is a special character used to make opening quotation marks. rʨanaɢ (talk) 05:25, 18 October 2010 (UTC)[reply]

What is this bird walking across the screen?[edit]

I've only seen it in the web sites of the Seattle Post-Intelligencer and the Asheville Citizen-Times. And I go to those sites only on a Firefox computer. Sometimes the bird is sweeping. But wherever he is, it's on a blank part of the screen.Vchimpanzee · talk · contributions · 18:44, 15 October 2010 (UTC)[reply]

Is it a pop-up ad? Many websites use animations or Adobe Flash to animate advertisements in distracting ways. Nimur (talk) 18:55, 15 October 2010 (UTC)[reply]
It is most probably a Flash animation. Roger (talk) 19:07, 15 October 2010 (UTC)[reply]
It's not a pop-up. It appears in the page itself. Here and here are some links. This doesn't guarantee the bird will show up. The first might be outdated but it'll get you to the site.Vchimpanzee · talk · contributions · 19:19, 15 October 2010 (UTC)[reply]
Try not to get lost in semantic arguments. By "pop-up", they are trying to tell you that there is an advertisement ON THE PAGE that you are seeing. It doesn't mean that something is literally popping up from the page. -- kainaw 20:46, 15 October 2010 (UTC)[reply]
Normally, a popup is a new window. That's what I meant.Vchimpanzee · talk · contributions · 21:18, 15 October 2010 (UTC)[reply]
That's old school (and blocked by most popup blockers). newer ads use flash/javascript/css combos that build ad content straight into the page itself. Don't see the bird you're talking about, though, so I can't say what it is. --Ludwigs2 21:24, 15 October 2010 (UTC)[reply]
I saw him, on the Seattle Pi page, he was mooching about sweeping up and whistling. He was in a white box with, in the top right hand corner, a "folded down corner" and the word "Videoegg". clicking the videoegg thingy brough up an advert for some car or something. I don't think he is a specific breed or species of bird. DuncanHill (talk) 21:31, 15 October 2010 (UTC)[reply]
Hey, you're using Firefox! That's great! Now go to the "Tools" menu, click "Add-ons", then click "Get Add-ons", then click the text field labeled "Search All Add-ons", then type "adblock", then choose to install "AdBlock Plus". Most ads will disappear and all the problems you've had in the past with ads will become distant memories. Comet Tuttle (talk) 00:00, 16 October 2010 (UTC)[reply]
No, I'm using Chrome. DuncanHill (talk) 00:01, 16 October 2010 (UTC)[reply]
The same extension in also in Chrome.Sir Stupidity (talk) 03:16, 16 October 2010 (UTC)[reply]
Responding to Comet Tuttle: they won't block the ads at the library. But that's the only place I've seen this bird. I don't go those sites at home.
I haven't asked a question here lately because ... well, I haven't had any specific new problems at home, and I know the site to go to in order to ask for help. Except I've never gotten a satisfactory answer to anything, but if all they can do is tell me to shut down add-ons and things like that, there's not really anything to solve.Vchimpanzee · talk · contributions · 15:36, 16 October 2010 (UTC)[reply]

Python question[edit]

OK, I'm still learning python and am confused by the following:

>>> a = (1,2,3)
>>> a*2
(1, 2, 3, 1, 2, 3)
>>> 2*a
(1, 2, 3, 1, 2, 3)
>>> 


Is there a pythonic reason for one of the two expressions not to return (1,1,2,2,3,3)? I am really asking what 'pythonic' means in this context.... Thanks, Robinh (talk) 19:22, 15 October 2010 (UTC)[reply]

The * operator for sequence types means "take n copies and concatenate them" (ref). So 2*(1,2,3) means (1,2,3)+(1,2,3), which is (1,2,3,1,2,3). -- Finlay McWalterTalk 19:35, 15 October 2010 (UTC)[reply]
Is there a more pythonic way to achieve the other result than tuple([(x,x) for x in a])? In particular, I find the tuple constructor inelegant. --Stephan Schulz (talk) 19:42, 15 October 2010 (UTC)[reply]
I don't know about "pythonic", more "haskellic":
               a=(1,2,3)   # the thing
               f=2         # how many copies
               reduce (lambda x,y: x+y, [a for z in range(0,f)])
Urgh. -- Finlay McWalterTalk 19:59, 15 October 2010 (UTC)[reply]
Now you spoiled my appetite! --Stephan Schulz (talk) 20:03, 15 October 2010 (UTC)[reply]
Oh, and it does not work (sorry, missed that at first). The question was how to get (1, 1, 2, 2, 3, 3) . --Stephan Schulz (talk) 20:06, 15 October 2010 (UTC)[reply]
Sorry, I thought you wanted a "pythonic" way to implement 2*(1,2,3) without the using the *. I'll have to have a think about the latter (but I'm eating, so later). -- Finlay McWalterTalk 20:14, 15 October 2010 (UTC)[reply]
Hold onto your lunch:
                       a=(1,2,3)   # the thing
                       f=2         # how many copies
                       reduce (lambda p,q: p+q, zip (*[a for z in range(0,f)]))
Double-urgh. I'm sure there are much cleaner ways than that. -- Finlay McWalterTalk 20:34, 15 October 2010 (UTC)[reply]
OP here again. I don't think I'm making myself clear. Is there a pythonic reason why a*b should not differ from b*a? Robinh (talk) 20:45, 15 October 2010 (UTC)[reply]
That's just a design implementation - they designed the operator to be commutative. There's no real reason to do it or not to do it, except that most algebraic operators (as opposed to set-theoretic operators) are commutative. --Ludwigs2 20:52, 15 October 2010 (UTC)[reply]
(edit conflict)It's defined that way; there's nothing deeper to it than that. Operators are just functions (in this case defined using the __mul__() and __rmul__() functions); they chose to have mul and rmul work the same; they could have chosen them to work differently. -- Finlay McWalterTalk 20:54, 15 October 2010 (UTC)[reply]
OK, I get this. So, given that (1,1,2,2,3,3) is apparently hard to get, and there appear to be two ways to get at (1,2,3,1,2,3) [viz, 2*a and a*2], and "pythonic" seems to mean "there is one right way to do things in python and the right way is the python way", and python appears to have the ability to define "*" to mean anything we want, what is unpythonic about defining "a*2" to mean (1,1,2,2,3,3)? Sorry to go on about something which seems to be obvious to the python gurus here. Best wishes, Robinh (talk) 22:03, 15 October 2010 (UTC)[reply]
"pythonic" often doesn't mean very much. Sometimes they mean "the thing you'd naively expect to get when you do this". Personally I don't find either the way it does do it to be obvious, nor the way you suggest, and I wouldn't have been surprised if 2*(1,2,3) == (2,4,6) instead. They chose to define this, but not to define (1,2,3)>>1 == (2,3,1), which might well seem obvious or intuitive. Frankly I fear you may be reading some textbook that's waxing lyrical about how semantically pure and wonderful Python is, and may be downplaying how arbitrary and bodgy it is. I really wouldn't worry too much about what is "pythonic", and I'd be suspicious of those who place emphasis on this (at the expense of just getting stuff done); it seems like a driving instructor trying to persuade you of the "zen of driving", when he should be showing you how the gears work. -- Finlay McWalterTalk 22:15, 15 October 2010 (UTC)[reply]
The use of * to mean list duplication is a pun on the word "times", so there's no strong reason to expect it to behave in any way like multiplication as we know it. The decision probably had more to do with not having too many different kinds of behavior hidden away. In particular, if they assigned particular different behaviors to 2*[1,2] and [1,2]*2, you'd need to memorize which is which. Lots of design decisions wind up being trade-offs between confusingness and power, like this. Paul (Stansifer) 22:21, 15 October 2010 (UTC)[reply]
When programmers design a language they usually have a few different considerations in mind: what will people learning the language expect? what features do programmers want? what are useful functions for the kinds of uses the language is expected to be put to? The python designers either didn't think to implement the particular feature you're interested in, or thought that implementing it that way would be more confusing than the particular implementation would be worth. --Ludwigs2 03:21, 16 October 2010 (UTC)[reply]
I think it's more that it plays off the common interpretation of multiplication as repeated addition. e.g. 4*3 = 4+4+4, so it makes some sense that (1,2,3)*3 is the same as (1,2,3) + (1,2,3) + (1,2,3). -- 174.24.199.14 (talk) 16:01, 16 October 2010 (UTC)[reply]
I guess there were two considerations that together led to this design choice:
  1. Some notation is needed for repeating a string n times. The operator * is the only one that every programmer who does not know the correct syntax and is simply trying things out is sure to try in one of their first attempts.
  2. It's hard to remember whether the syntax is "string * n" or "n * string". By making the operator commutative one can ensure that no programmer gets this detail wrong all the time.
These are both writability concerns, while a lot of the original motivation of Python was readability when compared to Perl. But I think they represent a good trade-off. Hans Adler 16:42, 16 October 2010 (UTC)[reply]

For python, most of these functions you want can be found in the itertools package:

from itertools import *
print list(chain.from_iterable(repeat(k,2) for k in [1,2,3]))

is most natural than it might seem at first. For Haskell, try

 concat [replicate 2 k | k <- [1,2,3]]

or better yet,

 concatMap (replicate 2) [1,2,3]

72.89.106.242 (talk) 06:10, 17 October 2010 (UTC)[reply]

eee pc 1005h ram type[edit]

what type of ram does eee pc 1005h take? Mine has 1 gb in it that it came with, is it hard for me to upgrade? What is the most ram I can put inside, and how much will that ram cost me? If it is very complicated to install, how much would a service center be likely to charge me for installation of the ram? Thank you. 85.181.50.90 (talk) 19:51, 15 October 2010 (UTC)[reply]

Crucial.com has a form you can fill in to find out what kind of memory can go in a given computer. According to it, for yours, "Each memory slot can hold DDR2 PC2-6400 with a maximum of 2GB per slot", and there is one slot. Looie496 (talk) 21:51, 15 October 2010 (UTC)[reply]
...And memory is easy to upgrade even on a netbook -- all you need is a little Phillips screwdriver and an ability to avoid static discharge. You can look at the back and see the little compartment that holds the memory chip. Looie496 (talk) 21:54, 15 October 2010 (UTC)[reply]
That explaination is incomplete. A netbook will almost definitely have SO-DIMM (although I'd check first instead of relying on me) so buying normal DDR2 DIMM would be a waste of money. In terms of the upgrade [1] may be helpful even if you don't understand German and will probably answer the question of how many slots and whether it uses SO-DIMM (my internet is slow at the moment and I pay for data so I can't be bothered watching it). BTW if it supports DDR2 you would normally be fine with any speed RAM. If it's slower then PC2-6400 your RAM speed will be limited which may affect performance (although I suspect not that much for most purposes in a netbook) if it's faster your RAM will be limited to the lower rate so it may be a waste if it costs more (but it may not). Occasionally with DDR I've heard of RAM not supporting lower rates by which I take it to mean it's not officially supported nor are there any SPD settings so your motherboard may not know what to do. Never heard of this with DDR2 although I'm not saying it hasn't happened. Nil Einne (talk) 09:37, 18 October 2010 (UTC)[reply]