Wikipedia:Reference desk/Archives/Computing/2009 October 2

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October 2

Digital Scale

Fellow Wikipedians: I am looking into buying a small scale for weighing out various amounts (anywhere from ~1 to 10 grams) of marijuana. I want something sorta cheap (under $30 ideally) yet accurate, with a precision of at least a tenth of a gram...better if possible. Can any of you recommend any scales online? I searched amazon.com but I'm not sure if I found anything worth buying. Thanks for the suggestions! --98.108.37.202 (talk) 00:06, 2 October 2009 (UTC)

My Python Integer Class

I'm trying to make a class that only contains a number that can only be an integer. It's a pet project that I'm working trying to simulate how the .NET Framework's structs limit the aspects of the variable. Can someone tell me if this code is syntactically correct and how to properly instantiate it:

class Int(object):
	def __new__(self):
		self.var=0
	def __init__(self, var):
		test=test(var)
		if test==True:
			self.int=var
		else:
			print("The variable entered isn't an integer.")
	def ret(self):
		print(self.int)
	def add(self, a):
		test=test(a)
		if test==True:
			self.int=self.int+a
		else:
			print("The variable entered isn't an integer.")
	def min1(self, a):
		test=test(a)
		if test==True:
			self.int=self.int-a
		else:
			print("The variable entered isn't an integer.")
	def mul(self, a):
		test=test(a)
		if test==True:
			self.int=self.int*a
		else:
			print("The variable entered isn't an integer.")
	def div1(self, a):
		test=test(a)
		if test==True:
			self.int=self.int/a
		else:
			print("The variable entered isn't an integer.")
	def min2(self, a):
		test=test(a)
		if test==True:
			self.int=a-self.int
		else:
			print("The variable entered isn't an integer.")
	def div2(self, a):
		test=test(a)
		if test==True:
			self.int=a/self.int
		else:
			print("The variable entered isn't an integer.")

-- --Melab±1 ☎ 00:27, 2 October 2009 (UTC)

Maybe I'm missing something here, but Python already has a built-in integer type called int. What behaviour do you want from your class that is different from int ? Gandalf61 (talk) 10:25, 2 October 2009 (UTC)

World Wide Web

Back in the early 90's, how did one use the World Wide Web. Furthermore, how did people use Usenet? 67.180.161.183 (talk) 04:18, 2 October 2009 (UTC)

Almost everyone used dial-up modems. I remember we sometimes connected to a service called Prodigy. You'd dial into that and browse their home page. But, there was so little to do on that (as a kid, that is), that we mostly used BBSs. We downloaded stuff from those (pictures, etc.), talked in chat rooms, and played text-only games. Although HTML had already been invented, web browsers like Netscape and Internet Explorer did not come into use until around 1995. So, in the early 1990s, we didn't really use the WWW. It was mostly text without HTML. Piracy was all done by hand, since modems were so slow. You'd borrow a game on a floppy disk from a friend and install it on your computer. I remember it took 10 minutes to download a single picture, and the computers were so slow that it would slowly appear on the screen. Of course, it was all really fast compared to the way it was in the 1980s. Later came America Online. In the early- and mid-1990s, most people used their ISP's home page (Prodigy, AOL, etc.) to check their e-mail, check the weather, etc. Yahoo! and Alta-Vista came along in the mid-1990s, but they were worthless at first. You just used them as portals and browsed lists of pages on them. They couldn't find anything that you wanted if you tried to use the search box. It wasn't until Google came around in the late 1990s that you could actually find something by searching. As for Usenet, I didn't use it very much, although I know you can read newsgroups like Usenet using Outlook Express. You can share files and of course talk on newsgroups.--Drknkn (talk) 04:37, 2 October 2009 (UTC)

Drknkn's description is broadly true for a certain set of home users. However, it misses some important points. The Web was created at a research institution (CERN) for the purpose of disseminating scientific papers and information; most of its early users would have been faculty, students, and employees at universities and companies with permanent Internet connections, not dial-up ISPs. But even then, the systems were quite slow by modern standards!

"Online services" such as AOL and Prodigy did not have Internet access until the mid-'90s; if you wanted that, you went to a dial-up ISP such as Netcom. The idea that ordinary people (outside of universities, the technology trades, or hobbyists) would want open and unrestricted Internet access took a long time to seep in.

As for Usenet -- In the early '90s, I would dial into a local hobbyist Unix system and use the "trn" software to read news. Downloading pictures from Usenet meant saving several messages to a file, running uudecode on them, and downloading with ZMODEM. Getting software would involve floppy disks or downloading from a BBS more often than Usenet. --FOo (talk) 07:18, 2 October 2009 (UTC)

Before world wide web there was Gopher ftp usenet and telnet. We would use a terminal in the computer lab, or dial into a serial port on a unix box using a terminal program on the PC. Then run commands on the unix machine. I think I may have used tin to read usenet. There were on line indexes around like Archie search engine and Veronica. When Mosaic first came out we wondered why would any one want to embed pictures in text? Graeme Bartlett (talk) 11:10, 2 October 2009 (UTC)

To sum it up: it was pretty slow, not very interesting. In the bad old early days, I had a lot more fun just basically posting to bulletin boards, occasionally playing text-only browser games. Where I was, it was a lot easier to connect to local machines than it was to connect to the internet, so our "online communities" consisted primarily of people who lived in the area code. 'Twas a simpler time, to be sure. ;-) Met my first girlfriend that way, if you can believe it! --Mr.98 (talk) 13:45, 2 October 2009 (UTC)

I would disagree with the assertion that it wasn't very interesting; the limitations provided a challenge that was solved in various clever ways (see ASCII art for example. I recall seeing a ASCII movie back in 1994-1995 or thereabouts that exploited the way text-based unix email programs would page down if you held down the space bar, essentially creating frames out of each page. I was part of the Eternal September, though technically I was a university student at the time. I used a text-based unix system at the school. Email was through Pine, usenet was done with tin (earlier it had been vi, which was horrible) and word-processing was done with a program called Pico. In many ways, I miss those old days - and I missed out on the great heydays when virtually everyone you met online was in some kind of post-secondary institution. Matt Deres (talk) 16:38, 2 October 2009 (UTC)

Wow, that was overwhelming. How did you "dial in" back then? Were there modems in the computer 67.180.161.183 (talk) 01:07, 3 October 2009 (UTC)

Most people who used the Internet in the early nineties were not connecting from home. Typically they would go to their university's computer lab. This is an important point.

Otherwise, yes. To connect to either the Internet or (more likely) a local BBS, they would use a telephone modem. Probably an extremely slow modem. If you were very lucky, you might have a 28,000bit/s modem. Those came out in 1994. Computers didn't typically come with built-in modems, though. You usually had to add your own. You had a choice of getting an add-on board for your computer, or a stand alone box that plugged into your serial port.

By the way, AOL, Prodigy, and Compuserve existed in the early 90's, but they weren't connected to the Internet yet! For example, AOL didn't offer any meaningful internet access until 1993 when it first started offering USENET. APL (talk) 02:46, 3 October 2009 (UTC)

Back in deep dark Africa where I am, we were lucky to have 28800 baud modems; 2400 baud was a lot more commonplace in the early 90's. And we used those to connect to BBS's, even back in the 80's when BBS's were very rare locally and we couldn't afford the telephone connect rates to overseas BBS's. In the early 90's I used the university connection but usenet was about the only service fast enough to be able to use to download (there was one local usenet host that everyone used). I remember we once tried to download a game walkthough via ftp connecting to the USA (I think it was 100K large) and it took the whole night to download!! WWW I think we only saw in 1994 and had no idea it was going to be that popular. Sandman30s (talk) 12:55, 3 October 2009 (UTC)

Photoshop

Is there a particular website that you can post them a trick image (like two headed people) and wait for their answer for how to make it in Photoshop?--Mikespedia (talk) 07:05, 2 October 2009 (UTC)

There's not a simple "one-click" way to digitally alter a photo. The fun stuff you see on, say, Photoshop Phriday, are manually edited. You might want a general purpose photoshop tutorial site to learn the tools available; but there's a good amount of "art" and technique to making a reasonable-looking image. Nimur (talk) 07:37, 2 October 2009 (UTC)

The answer to 90% of questions about "how to make it in Photoshop" is 1. clone tool, 2. masking, 3. patience. --Mr.98 (talk) 13:33, 2 October 2009 (UTC)

And layers. It's vitally important to keep things on different layers and mask them, instead of just plopping stuff down on the background layer. It's surprising how many people forget this. APL (talk) 14:37, 2 October 2009 (UTC)

If you have a specific picture in mind - we might be able to help you right here...but it's hard to imagine a site like that existing specifically. SteveBaker (talk) 03:28, 3 October 2009 (UTC)

How do I make portable apps?

How can I make portable apps? I know some websites offer them, but I want to have the power to make my own... Are there any special tools for that? —Preceding unsigned comment added by 85.241.114.62 (talk) 10:58, 2 October 2009 (UTC)

Take a look at Portable application creators (In my personal experience, VMware ThinApp and Xenocode are the best). --SF007 (talk) 11:12, 2 October 2009 (UTC)

The above software is really good but can cause problems sometimes, especially with updating or adding plug-ins and stuff like that, because all files are stored in an executable file which can't be modified. For an alternative approach, have a look here where there are some tools and guides for making portable apps which retain the original file structure. It also depends of what type of program you wish to make portable (not all work well in portable form, some not at all) and the environment you're going to run them in (some portable apps might require java to be installed on the host system for example, and won't run without it)

Stablemotherboard

Is there any motherboard which will be stable in hot temperature (no freezing or lock up)? Is Asus P5Q EM is appropriate for that job? Any thoughts? --119.30.36.51 (talk) 11:43, 2 October 2009 (UTC)

Obvious Question : How hot?

The probably is that the motherboard itself is not your point of failure here, it's the CPU. Without a special cooling system, the hotter the surrounding air, the less effective the CPU's heat-sink will be, and the faster it will overheat.

You'll also want to keep close watch on your video card's temperature as well.

What's your application? Are you married to the x86 (PC) architecture, or are you willing to use something else. It's my understanding that ARM CPUs are not nearly as heat sensitive as Pentiums and whatnot. If a rather low powered Linux machine would suit your needs, you might be able to put something together around the BeagleBoard, but I can't seem to easily find specs on what temperature range it's happy with. APL (talk) 12:57, 2 October 2009 (UTC)

(after EC) Does "hot" refer to the ambient room temperature, the computer's internal case temperature, or the CPU core temperature? This is an important consideration. ARMs and other low-power devices may be able to operate at higher ambient room temperature because they don't need as much thermal dissipation (they are typically lower power than, say, a Pentium Core 2). But I'd be willing to bet that their thermal shutdown core temperature is not that different from a higher-power CPU: Thermal Design Guidelines for 423-pin Pentium 4 and for 80331 (Celeron); meanwhile, even a high-end ARM runs at 300 mW. But if your case temperature were very high from something else, the ARM will probably fail. It looks like ARM does not publish thermal tolerances for operation (only storage) - so I suspect they have not been tested or certified to pass certain thermal benchmarks. (Surprisingly, even their automotive- processors do not have thermal tolerances listed - this is usually a major component of automotive electronics design!) So in general, while they are cooler processors under normal conditions due to their low power dissipation, if you have a special need (e.g. running the device inside a hot car, or even long-term exposure to an un-airconditioned server room), you might actually find a hotter P4 more robust and reliable. Nimur (talk) 13:38, 2 October 2009 (UTC)

• Too hot that causes a system to freeze and it forced user to press reset button. As far as I know Overheating of CPU causes system to shut down or restart repeatedly, but not freezing or locking up the system. My video card is not overheating as it is idle in 43 degree and 60 in load. Processor temp is 27 degree to 34 degree Celsius. Ram is not problem. I have conducted numerous test on system.

Yes I am planning to load Vista 64 bit soon. But need an stable gaming motherboard. Should I go for that Asus model?--119.30.36.51 (talk) 13:33, 2 October 2009 (UTC)

For normal gaming usage, I think what you really want is good fans, and a good heat-sink. And good airflow. (Keep your case closed, And don't go adding vents or fans in random locations without thinking about what this does to your overall airflow.) In my experience choosing the right case is just as important as the CPU in these sorts of issues.

If this computer is more than a few months old, be sure that dust is not accumulating on your heat-sinks. That can severely limit their effectiveness. Clear that out with compressed air. APL (talk) 14:36, 2 October 2009 (UTC)

• I have all the necessary instruments for a gaming system. For example, I have full tower thermaltake Xaser VI case. I have XFX 750i SLI mobo which runs too hot that causes system to freeze. That mobo is proven to be unstable. Does Asus P5Q EM have good heat-sink?--119.30.36.34 (talk) 16:21, 2 October 2009 (UTC)

Back button won't go back in Yahoo email

This [1] is where the discussion began. Actually, a link there goes to where my computer information is. In summary, when I finished looking at an email and tried to go back to what I was doing, I couldn't. I ended up in an endless loop. This may also be related to this [2], a problem I also have on other sites.

The advice I was given by someone from Yahoo was that it might be a Java problem. As it happens, I kept getting messages that Java needed to be updated, so I did. This has not solved the problem. I also keep getting Error Code 21. So far they haven't responded back. I was wondering if anyone might have anything to say.Vchimpanzee · talk · contributions · 17:40, 2 October 2009 (UTC)

You could use an email client. Evolution is a good one, and Opera comes with built-in email reader that isn't bad either. The plus side would be that you are not dependent on some yahoo provided interface that will be changed and gone when they feel like it. Otherwise the best you can do is to clear all caches, make sure you are running latest versions and, if all else fails, reinstall everything. --194.197.235.240 (talk) 18:48, 2 October 2009 (UTC)

It's simpler just to remember not to go to Yahoo except when I first sign on. Which kind of defeats the purpose of the simple link to email at the top of the page. As for getting anywhere within Yahoo, I can always click on "Inbox" or whatever folder. At least that always works now. And no problems with losing my drafts lately either.Vchimpanzee · talk · contributions · 19:26, 2 October 2009 (UTC)

I've been reading Vchimpanzee's postings here over the past few months with mild concern/amusement. You seem to have so many problems with your browser/PC that I'm starting to think you should just format and re-install everything. Honestly, I've never come across anyone having this much trouble on so many different websites and with such a disparate variety of issues that one can't even begin to get to the root of the problem. You sir/madam have a very sick PC which either has some serious corruption/improperly installed software, or bad bad BAD case of malware/spyware. Seriously, format and re-install. It's just not funny any more. Zunaid 20:14, 2 October 2009 (UTC)

The back button worked just now.

Nothing's wrong with my computer. Norton scans it every Friday and never finds anything but cookies. I keep away from unfamiliar sites.Vchimpanzee · talk · contributions · 20:36, 2 October 2009 (UTC)

A clean Norton scan does not mean "nothing's wrong with my computer". PCs tend to accumulate problems over the months and years as the user downloads, installs, and uninstalls software.

I am not sure that Vchimpanzee's computer is as awful as Zunaid seems to believe. I think most of his/her complaints are about small, common problems that most of us would not think twice about, and Vchimpanzee is complaining here because of the ease of doing so.

Vchimpanzee, I, for one, am tired of answering your daily questions and comments about problems with Yahoo Mail on your particular PC. I, and several others, have told you the fix for the problem many times. Switch to a different mail provider. You don't have to put up with this crap. Just switch to a different mail provider. Or, format your PC's hard disk and reinstall everything from scratch if you are for some reason hellbent on staying with Yahoo Mail. That is as far as I can go. We have told you how to fix all of this. Comet Tuttle (talk) 20:55, 2 October 2009 (UTC)

I don't see what's so wrong with being curious to learn what causes things. I think the problem may be with Internet Explorer 8, as I said in a question with a link above. I never got a clear answer on whether Internet Explorer 8 has any problems, or how to find out. In any case, there are no obvious problems with the computer. I saw an AT&T ad when the "Not Responding" message was there. An earlier question of mine was about an AT&T ad with Firefox at a library. I despise Firefox. Nevertheless, going to unfamiliar or troublesome sites there is less risky. The latest Firefox update seems to have solved the AT&T problem, or maybe AT&T did.

NO more questions for at least a week because I think I'll be at the beach. Something could change but that's my plan.Vchimpanzee · talk · contributions · 21:42, 2 October 2009 (UTC)

Chimp, ignore them. It's not your computer, it's Yahoo's. Recent software updates took a long time to flow through to every server, and caused problems which took a while for them to fix. The way Internet Explorer interprets Javascript may be one factor in your case; the way it does not handle mouse-hover instructions well is another. Your using Norton is a third...there have been numerous problems caused by minor updates to Norton, and one major one that nearly halted the whole Yahoo mail system a few months back. At least set your Norton to never update automatically, that way you will know when it did so, and be able to make the connection between that and any new mail problems.

Once you have the mail page open, DO open mails into a separate tab, so you don't have to use the back button to get back to the inbox. If a page goes blank or freezes, forget about trying to refresh it. It is dead. Close it, and open a new copy of Mail.

Yahoo has a help section for mail, which won't tell you anything useful. It also has a mail problems suggestion board, which is fairly deserted. The best place to take a problem like this is the general Answers suggestion board, which is well serviced by regulars who also use mail, therefore can give you the best currently known work-arounds. You don't need an Answers account to use that board,just a Yahoo email address. - KoolerStill (talk) 20:51, 4 October 2009 (UTC)

Keeping files on a hard disk without registering in file system (FAT32 or NTFS)

Is there a program for writing files directly to hard disk without registering it in File Allocation Table or whatever it is called under NTFS (just writing it into empty space hoping it won't be overwritten later on) and keeping record of it on some portable disk together with checksum?? and restoring it in case no part of it was overwritten? —Preceding unsigned comment added by 213.8.52.97 (talk) 20:19, 2 October 2009 (UTC)

TrueCrypt doesn't do exactly what you ask for, but appears to be able to create hidden volumes in ntfs and probably is what you really want. --194.197.235.240 (talk) 20:49, 2 October 2009 (UTC)

You can write directly to a device in Linux. For example, I have a drive at /dev/sda1. I can manipulate it with any file handler, but I'm sure to screw up the data on the drive by doing so. The only time I've treated a drive like that (going straight to the device) is to read it and find deleted files that I wanted to restore. Now, I'm remembering back on the Commodore 64. It was trivial to open the floppy disk in a binary editor and change the data byte by byte. I thought it would be kind of cool to type out a letter to someone that way - which could only be read by reading the disk in another binary editor. Of course, I was a young idiot at the time. -- kainaw™ 01:57, 3 October 2009 (UTC)

Well, I guess that would be kinda like creating the file - then deleting it again. Then it's on the hard drive - but you've deleted it from the FAT, etc. I'm not quite sure what the advantage is though...if you're thinking it's some kind of security - I rather doubt it. This is a case of Security through obscurity - and it's not a good technique. SteveBaker (talk) 03:25, 3 October 2009 (UTC)