Wikipedia:Reference desk/Archives/Computing/2011 February 9

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Computing desk
< February 8 << Jan | February | Mar >> February 10 >
Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

February 9[edit]

I think I am dating myself[edit]

I am trying to do research right now on early Wikipedia. So I am doing asking:

  • Is there anyway to search through old Usenet posts? or Some search engine that will help with this?
  • Is there any sources that link the old usenet community with the early Wikipedia Community?

I am honestly not sure how use net used to work. So be easy one me. The Resident Anthropologist (talk) 04:47, 9 February 2011 (UTC)

For question 1, try Google Groups Nil Einne (talk) 07:41, 9 February 2011 (UTC)
Free direct Usenet access is available - I use but there are others too. Google groups is for kiddies and wannabes who have never even heard of Usenet.
If you want to try dating someone else, there are websites for that too. <joke> Roger (talk) 07:56, 9 February 2011 (UTC)
Kindly explain how 'free direct usenet access' allows you to search old usenet posts, from the ops question we can presume around 2001-2002 or earlier, when you haven't been keeping archives yourself, and retention of these servers is around 2 years at best [1].
And if you want to go further, I don't actually know if there are even commercial servers with 10 year text group retention, but it's not clear why the OP would need such things when in all likelihood Google Groups warts and all provides a far better search experience then anything off the shelf the OP can find even if they did get commercial direct usenet access particularly since if they want to search a diverse set of groups and a diverse range of dates we're talking many, many gigabytes of data probably in to the terabyte range or higher and we can presume from the fact they asked such a simple question setting up some sort of customised searching solution is probably beyond their means. Not to mention Google Groups completion isn't that bad from what I've seen, nor from memory was DejaNews they inherited their archives from (and I believe they may have made efforts to improve their completion after they took over anyway or may be I'm remembering wrong and it was in fact DejaNews that was trying to improve their completion at one stage) so even if you do find this 10 year+ retention commercial service and then have enough space, bandwidth, computing power and software to manage/search these 10 year+ of text groups I'm far from convinced your completion would be anywhere near as good for those old years so it's still highly questionable how this would be better. Of course GG does respect those not wanting their posts archived whereas a 10+ year retention server if it exists probably still keeps those posts after 10+ years so I guess that's one minor advantage. (Well I suspect GG does as well, it just doesn't allow access to them.)
Oh and not to mention Google Groups does at least stop people replying to very old posts (at least I know they used to) whereas with your 'free direct usenet access' I suspect a lot of software isn't going to make noise if you try to post a follow up to a 10 year old post, but you can bet other people in whatever newsgroup/s you cross/post to aren't going to be happy. The OP didn't indicate any intention to do so, on the other hand given their plans this may have been a risk if they aren't careful.
So all in all, I don't see any particular reason to recommend 'free direct usenet access' or anything other then some existing service which allows you to search archives of usenet posts directly (of which GG is the most prominent and in fact possibly only service nowadays, I seem to recall there was something else in the DN days but they weren't anywhere near as good and they don't seem to be mention in any relevant article which suggests to me even if they still exist they aren't worth considering).
Of course if you want to get in to usenet now, 'free direct usenet' may be worth considering, however this doesn't seem to be what the OP wants and considering your post, I'm sure I don't have to say it's always wise to read the question or follow the thread before responding rather the picking up a key word and hoping what you say is on topic.
Nil Einne (talk) 13:44, 9 February 2011 (UTC)
I was unsure of Google groups if it was google created to fill the void but I am learning very fast now that usenet is alive and well.

You should definitely read the Usenet article to get a better fix on this. Because Usenet was (and is) a distributed system with no central repository, there actually is no definite list of posts for an archive to contain -- each Usenet server would get a different sequence of posts. I believe that some of the more important and scholarly groups were archived in an informal way, but many certainly were not. Archiving Usenet would in some ways be like archiving BitTorrent, if that comparison means anything to you. Looie496 (talk) 18:10, 9 February 2011 (UTC)

Ah that is indeed helpful, I read the article but failed to fully grasp the concept. The analogy of bit torrent makes alot of sense. I guess alt.religion.scientology would be archived some where most likely? The Resident Anthropologist (talk) 19:50, 9 February 2011 (UTC)
Alt groups would be the least likely to be archived, comp groups probably the most likely. Looie496 (talk) 05:19, 10 February 2011 (UTC)
Like just about every other discussion group, [alt.religion.scientology is on google groups]. (talk) 06:38, 13 February 2011 (UTC)


whats the hexadecimal equivalant of the Binary Coded Decimal number 011111000? —Preceding unsigned comment added by (talk) 12:22, 9 February 2011 (UTC)

Google is your friend. Binary to Decimal, Decimal to Hex. Lots of free tools out there to do this. Your default calculator on your computer (e.g. Calc.exe) can probably do this as well. --Mr.98 (talk) 13:45, 9 February 2011 (UTC)
Binary Coded Decimal is a little less straightforward than simple binary-to-hex conversion. A BCD number should be a multiple of four bits long, so I'm not sure how to interpret the 9-bit string the OP gives. Also, if we ignore the leading 0 and use 1111 1000, then it's not a valid BCD number, as only values 0000 - 0101 are used. Rojomoke (talk) 14:35, 9 February 2011 (UTC)
Yes, there must be some sort of transcription error, the string as written cannot be BCD. Alternately, if the last 0 is omitted, we have 0111 1100, which could be +7 if the last string is the sign convention 1100=C=positive. SemanticMantis (talk) 19:07, 9 February 2011 (UTC)
Yet another interpretation is that the OP wrote too many 1's, meaning to write 01111000. In BCD, 0111 1000 is '78', which is '4E' in hex. Astronaut (talk) 12:14, 10 February 2011 (UTC)

Batch convert .bmp (only) to .png[edit]

Is there are free Windows software that I can point at a directory, and it goes through it and converts all the .bmp files (but not anything else) into .png files, preferably including deleting the original .bmp files also please? Searching on Google, I have only been able to find things that require you to mark every file you want converted. Thanks (talk) 14:07, 9 February 2011 (UTC) (talk) 14:16, 9 February 2011 (UTC)
ImageMagick could probably do it easy enough, if you don't mind using command line tools. Once image magic was installed, I think the command you want would be "mogrify -format png *.bmp". That should modify every .bmp in the current directory into a .png file. APL (talk) 15:32, 9 February 2011 (UTC)
I'd use ImageMagick, but I think irfanview does conversion, too — might be more Windowsy. ¦ Reisio (talk) 05:48, 10 February 2011 (UTC)

photo from telephone to computer[edit]

how do I transfer using bluetooth? Kittybrewster 14:12, 9 February 2011 (UTC)

It depends on the make of phone. What kind is it? Marnanel (talk) 14:19, 9 February 2011 (UTC)
Samsung Monte slider. Kittybrewster 14:43, 9 February 2011 (UTC)
On my computer (a MacBook), in the Bluetooth settings, I tell the MacBook to let me browse the files on my Bluetooth device. This sends a request to the phone, which then says, "Are you sure you want to let this computer browse me?" and I say "yes" on the phone, at which point I can then, from the computer, force the phone to send me the photos. (In my case, it makes me to it one photo at a time, and I have to confirm each time on the phone, but oh well). Not sure how that translates into your computer and phone. It requires the phone's Bluetooth mode to be set to "findable," I believe. --Mr.98 (talk) 14:51, 9 February 2011 (UTC)
It will most likely be much easier to do a photo message (text message with photo attached) to the email account you use on the computer. Instead of a phone number, just put in an email address. Then, open your email and save the attachment. This avoids security blockades on both the computer and phone. For example, I just found out, after two days of searching, that to view the files on my phone through a USB connection, I have to do a slide-down motion on the USB icon, select security, select file system, and then press the "turn on file sharing" option. I didn't even know I could do a slide-down motion on the USB icon, so I would have never figured it out on my own. -- kainaw 19:33, 9 February 2011 (UTC)
Though of course if you don't have a data plan, it can cost you quite a bit to send photos that way. --Mr.98 (talk) 23:28, 9 February 2011 (UTC)
You don't need a data plan. You need a txt plan. I have unlimited txt messages, but no data plan. Sending/receiving email through SMS is covered by the unlimited txt plan. -- kainaw 14:00, 10 February 2011 (UTC)

alt-codes in Firefox[edit]

There are certain alt-codes I use for special characters that work in Word Processors and other places, but not in my internet browser. For example, alt-0601 should give me ə but in Firefox it gives me "Y". I assume this is some kind of character encoding issue with my browser, but I don't know how to rectify it. How can I get those codes to work in Firefox? Cevlakohn (talk) 15:07, 9 February 2011 (UTC)

It works for me if I use num-lock. Kittybrewster 15:57, 9 February 2011 (UTC)
It will depend entirely on what font you are using. Take a look at your character map (run charmap.exe) and you will find that alt-0601 produces various characters depending on the font.--Shantavira|feed me 16:59, 9 February 2011 (UTC)
How to enter Unicode characters in Microsoft Windows might be helpful (also the UnicodeInput utility linked from that page). -- BenRG (talk) 09:35, 11 February 2011 (UTC)

Is there a way to restrict a Google search to an absolutely exact phrase?[edit]

By that I mean it must search only for the absolutely perfectly identical match. No variation in punctuation or any other "close matches" allowed. It's must be an absolutely perfect match in all respects. (Ok maybe the font is allowed to be different but that is all!) I am looking for a specific idiosyncratically punctuated variant of a very common phrase. If any variations would be included in the search result it would return so many hits as to be completely useless. The normal Google advanced search option of "exact phrase" isn't even in the same galaxy as the meaning of "exact" that I require because Google doesn't seem to care if a comma or a capital is different from the "exact phrase" entered in the search. Roger (talk) 17:46, 9 February 2011 (UTC)

Maybe there is another search engine that does allow restriction to such genuinely exact matches? Roger (talk) 17:47, 9 February 2011 (UTC)
It seems, on cursory inspection, that Bing ( respects exact "quoted text" strings more than Google, but with some exceptions (in some cases, you may have to scroll past 1 or 2 non-literal string-search results to see the "exact matches" results). And, it seems that punctuation is still discounted in the definition of "exact match." In general, modern search indexes are much more complicated databases of meta-information and "signals"; it may not even be possible to use a modern search engine to perform a "strcmp" style string search. Of course, small indexes of web-data can be locally cached using wget, and you can use your operating system's file search tools to scan for exact matches... Nimur (talk) 18:29, 9 February 2011 (UTC)
After more testing, I'm going to rescind my earlier claim that Bing respected quoted text strings. Nimur (talk) 18:32, 9 February 2011 (UTC)
Down with heuristics!!! This sucks, I was hoping to use a wacky quote I once read, but need to cite, in an article I'm writing (not on WP). Thanks for your efforts Nimur, but it seems I'll have to do without it. Down with heuristics!!! <sulk> Roger (talk) 18:50, 9 February 2011 (UTC)
Search engines almost never respect capitalization and punctuation in their indices because people don't generally want those things distinguished in the results they get (though the recent arrival of automatic synonym search has made that less of a problem). If you add a plus sign in front of each word in a phrase search, Google will turn off synonymization for that word, at least. Google's code search almost certainly hasn't indexed what you want, but it is the only search engine that I know of that respects punctuation exactly. You can even search it for regexps; I'm not sure how they manage that.
What is the phrase that you're looking for? Maybe there's some other approach. Paul (Stansifer) 22:13, 9 February 2011 (UTC)
I's a line from a sterotypical Mafia movie where the boss says "Speak with I" while interrogating one of his minions who has double-crossed him. The meaning of the phrase being "Talk or else..."
I need to find out which movie it comes from. Googling "Speak with I" just delivers a whole lot of variations. Roger (talk) 09:56, 10 February 2011 (UTC)
Unlike Google, Duck Duck Go doesn't return any results with a period after "speak with": [2] It looks like it respects some punctuation in quotes (Google: "wait I" DDG: "wait I" DDG: "wait, I") Anyways, after looking at the Google and DDG search results with the words "movie", "mafia", and "quote", I suspect that, if it's from a movie, it's a pretty obscure movie, and it's probably not online at all. Paul (Stansifer) 12:39, 10 February 2011 (UTC)
My experience is that Google will give you exact matches at the top of the results if it finds any. The fact that you aren't seeing any probably means that it isn't finding any. If you do a Google Books search, for example, you will find a few exact matches with "speak with I" at the top of the results -- although none of them are what you want. Looie496 (talk) 17:36, 10 February 2011 (UTC)

Script to save/restore Firefox settings (Linux)[edit]

Does anyone know of a script to save and restore selected Firefox settings like bookmarks, stored usernames/passwords, add-ons, etc.?

It seems that some profiles on one of my Linux multi-user systems became unstable; so far, the only thing that helped was exporting the bookmarks, making a list of the installed add-ons, deleting "~/.mozilla", then restoring the saved bookmarks and re-installing all the add-ons by hand.

This is time-consuming and error-prone.

Does anyone know of a script that could handle this? Simply copying all the files from the old "~/.mozilla" directory will copy all the bugs causing the malfunction as well, so that doesn't help - I need to load the contents of the old configuration into pristine configuration files, so to speak.

NB: I could not find anything in common between the profiles that got damaged (no single add-on that was used by all of them, etc.). :-(

-- (talk) 20:21, 9 February 2011 (UTC)

Do you have extensions/add-ons? If you open a Terminal Window, and then enter "firefox -safe-mode &" (sans quotes), then firefox will start with all your extensions and greasemonkey scripts etc disabled. You can then choose to permanently disable all of them. They can be re-enabled via Tools/Add-Ons. CS Miller (talk) 21:35, 9 February 2011 (UTC)
Yes, these users have extensions/add-ons, however, I haven't been able to figure out if - and if yes, which - add-ons cause the trouble (it might be something totally unrelated). So the question remains - how can I extract bookmarks, add-ons, etc. from a botched profile and reinsert them in a newly created one, without doing it by hand for every affected profile? -- (talk) 21:43, 9 February 2011 (UTC)
For addons you will have to make backups before there is trouble, or save a list of which you've installed, and their XPIs. For bookmarks, you should almost always be able to dump them from sqlite/etc., but redundant backups are the only full proof solution. There's no silver bullet short of proper backups, sorry. ¦ Reisio (talk) 05:57, 10 February 2011 (UTC)

Java: Main vs Run Methods[edit]

Hi, Could someone explain the difference between the static public void main() function (which seems to be what a class loads no matter what)


public void main()


public void run()

thanks! — Preceding unsigned comment added by Legolas52 (talkcontribs) 20:26, 9 February 2011 (UTC)

public static void main(String[] args) is the signature of the method that the JVM will invoke when you start a Java program: java com.example.frobozz.Frotz to invoke Frotz.main(). Your second example has no particular meaning (and is likely to confuse). The third is the method in java.lang.Runnable (which is implemented by java.lang.Thread among others) that is invoked in a new thread (other than the main thread already discussed). --Tardis (talk) 20:34, 9 February 2011 (UTC)
To expand a bit more on the third one, run is part of the interface of Runnable, so classes that implement Runnable have one in order that they can, well, be run. A name that has a special meaning to an interface doesn't have any special meaning in classes that don't implement that interface. Paul (Stansifer) 22:23, 9 February 2011 (UTC)

There are many things that need to be addressed here. In Java, public static void main(String[] args) is a special method that is the only one that can be used to start a Java application. The method must be public, static and void, must be named main, and must take one String[] parameter. The only thing that can be changed is the name of the parameter. main(), taking no parameters, is just a plain Java method with no special significance. The difference between static and non-static methods is very important. Static methods are like your old-fashioned procedural methods. They don't need an object instance to act upon. It's entirely possible to write a whole Java program by only ever calling static methods, but that wouldn't be very object-oriented. A non-static method (sometimes called an "instance method"), on the other hand, acts on a specific object instance, with direct access to that object's state. One way to visualise the difference is to think that to call a static method means "do this thing with this object" while calling a non-static method means "tell this object to do this thing". It is an error in Java to have both a static and a non-static method with the same signature (i.e. the same name and the same parameters).

To answer your question, the difference between the first two is simply that one is static and the other is non-static. The difference between the last two is that they have different names, which means that they are different methods altogether. You were probably thinking of public static void main(String[] args), which is the method that starts a Java application. JIP | Talk 20:36, 10 February 2011 (UTC)

iOS SDK on older macs[edit]

I've seen online that the iOS 2.0 SDK can be made to run on powerpc macs, even though apple said it needed intel macs. Does anyone know if the iOS 3 or 4 sdks can be similarly made to work on these older macs? --Thekmc (talk) 20:46, 9 February 2011 (UTC)

MS Access 2007 question. How do I record a keyboard shortcut to tell the DBPIX plug-in to rotate the view of the image?[edit]

Hi, this question is kinda vague because I'm just getting to know MS Access now. Because I have a data entry job.

So, I'm using MS Access runtime 2007 plus the DBPix plug-in to view records. Each record has an image containing data I need to enter into the database.

The problem is some images need to be rotated. I can do this using the mouse. Right-click, select rotate from the pop-up menu, and that's it.

What I want is a keyboard key (fex, F1 or something) to do the image rotate. What are the basic steps I'm looking to do?

Thanks, -- (talk) 21:10, 9 February 2011 (UTC)

You can almost surely do this with Access's own VBA, but to my knowledge you can't program that like recording a macro in other programs. (Annoying? Welcome to Access.) Are you comfortable with VBA? The basic instructions are that you modify the Form's OnKeyPress function, have it check for the key in question (e.g. that it is F1 or whatever), then tell the DBPix control to perform the rotation. It is not a very hard bit of scripting, but if you are new to scripting, it will require a bit of explanation more than what I've just given. --Mr.98 (talk) 21:17, 9 February 2011 (UTC)

Ok - Thanks. That's really helpful information. I'll download VBA and try it. I'm a java (eclipse) fan. I understand Visual Basic ui builder kinda deal though. Do you think I'll have to buy DBPix though? Right now, I'm using the free 'runtime' plugin that DBPix provides. (For that matter, I'm also using the MS Access Runtime as well.) I might have to buy the DBpix plug-in ($139) to program the keyboard shortcut in VBA, right? Thanks,

-- (talk) 01:14, 10 February 2011 (UTC)

The VBA is already inside Access — no downloading needed. It's not really Visual Basic, it's Access's own form editing UI. --Mr.98 (talk) 02:29, 10 February 2011 (UTC)

Oh - that helps. Thanks. — Preceding unsigned comment added by InverseSubstance (talkcontribs) 03:12, 10 February 2011 (UTC)

Why are 2 Amp USB rechargers faster?[edit]

I have a 1 amp and a 2 amp USB charger for a smartphone. Even when using the same USB cable, the 2 amp is always faster to recharge my device. Why is this? -- (talk) 23:06, 9 February 2011 (UTC)

Well, to be perfectly straightforward, the 2 amp charger provides twice as much electrical current as the 1 amp charger.
The wire itself doesn't really matter as long as it's reasonable quality, and you're not trying to use it for something that's way out of it's rating. APL (talk) 23:18, 9 February 2011 (UTC)
APL is correct, but to be more specific: power is equal to amperage multiplied by voltage, but also equal to work divided by time. leaving voltage the same and doubling the amperage will also mean if the amount of work is the same, the time halves. (talk) 03:39, 10 February 2011 (UTC)
You should also be aware that, in nearly all circumstances, the 2 amp charger will operate less efficiently than the 1 amp charger because of the charge characteristics of the battery in the phone. This means that it will take more than half as long to charge with the 2 amp charger, the phone will get hotter, battery life will be slightly shortened and some energy will be wasted. If the phone is designed for a 2 amp charger, then this is not a serious problem. Dbfirs 08:31, 10 February 2011 (UTC)