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January 8

Disentangle charity and personal email addresses on FB

Hi. In the tiny bit of spare time not lavished on Wikipedia, I run a charity. I set up its Facebook page as a 'business' page (or whatever FB calls them) when I was logged in as me. I'd quite like to associate the charity's email address to the charity's page, instead of my personal one, but I cannot for the life of me work out how to do it. Happy to follow steps on a web browser or in Android app. Go easy on me, I'm not a tech savvy person. Thanks, --Dweller (talk) Become old fashioned! 20:52, 8 January 2019 (UTC)[reply]

Dweller, instead of doing that, could you just shut down the charity's page and start over again? Or would that entail too much work for other reasons? Nyttend (talk) 02:22, 13 January 2019 (UTC)[reply]

Nice thought. I can't do that. We'd lose a hard-won following and history of dialogue and engagement. --Dweller (talk) Become old fashioned! 12:19, 13 January 2019 (UTC)[reply]

January 9

Question about PC cooling fans

I am replacing my 10-year-old PC with something a bit more modern. and have a question about the new(er) PWM fans. My old system just fed 12V to the fans with no speed control.

The CPU cooler I have chosen has 3 PWM fans, and the motherboard has a single 4-pin PWN CPU fan connector. The pins on the MB are:

1 GND
2 Voltage Speed Control
3 Sense
4 PWM Speed Control

I believe pin 2 lets me use a 3-pin voltage control fan, but my fans are all PWM.

My question is this: assuming that I stay within the current limit, is it OK to connect all of the fans in parallel? Or do I need a small fan controller? That sense pin concerns me; I doubt that it will be able to sense the fan speed of three fans connected together. Is the sense line even used on a PWM fan? --Guy Macon (talk) 18:18, 9 January 2019 (UTC)[reply]

AFAIK the sense line is unrelated to the type of speed control the fan uses. It's used assuming the fan and mobo support it. Note that it has nothing to do with the speed control or otherwise the operation of the fan, it's simply so that you can monitor the fan speed. In the 3 pin days, there was no problem using fans in parallel provided you didn't exceed the current limit although because of the way the sense works I doubt connecting all the senses work work and indeed most commercial parallel connectors only connected one of the sense connectors to the motherboard. I think this remains the case in the 4 pin days, but I admit I'm not sure. Nil Einne (talk) 10:43, 10 January 2019 (UTC)[reply]

I had a quick look and found this. [1] It sounds to me like using the fans in parallel should work even with 4 pin fans although you probably understand it better than me. (To be clear, as with 3 pin fans you should only connect the sense on one fan although I don't think it will damage anything if you connect both, instead your fan speed won't work properly.) Again I think it's how most commercial ones designed by anyone competent are made [2] [3] [4] [5] BTW the first source reminds me of something I think I've read before, it's not entirely connect that the sense is unrelated to the fan speed control I guess. The sense works better when you use the 4th pin for speed control, if you simply PWM control the voltage as was common in the past, the sense may not work properly although again this doesn't affect the speed control or the fan in any way unless your system actually uses the reported speed in some way besides simple monitoring. Nil Einne (talk) 11:50, 10 January 2019 (UTC)[reply]

Thanks! I don't see any downside to disconnecting the sense line to two of the three fans when using four-wire PWM fan control, So I am going to do that. --Guy Macon (talk) 16:21, 11 January 2019 (UTC)[reply]

January 10

which wifi repeater has the longest range

range of the signal transmitted from antenna, need the highest, in meters.Mussharraf Hossen Shoikot (talk) 08:17, 10 January 2019 (UTC)[reply]

They all transmit around 1 millwatt. However you can make a big difference by adding a parabolic antenna to focus the signal in one direction. If a repeater at the other end of the required transmission path also has a parabolic reflector the range can be several kilometers. Graeme Bartlett (talk) 12:38, 10 January 2019 (UTC)[reply]

There is an article on this: Long-range Wi-Fi. Graeme Bartlett (talk) 21:17, 10 January 2019 (UTC)[reply]

In general for WiFi, the one with the best antenna. Try shopping for antennae, rather than the box itself. Three antennae are useful too, as they permit diversity, which can be useful if the problem is localised dead spots owing to a building structure, more than simple range. Andy Dingley (talk) 16:05, 12 January 2019 (UTC)[reply]

How do I add the pkgsrc-wip repository to my netbsd?

How Do I add the pkgsrc-wip repository to my netbsd?177.92.128.62 (talk) 10:22, 10 January 2019 (UTC)[reply]

Follow the instructions at pkgsrc.org/wip, assuming you already know what you're doing. If you aren't already pretty familiar with some basic background knowledge, like how to use the Git software tool, you have a lot of prerequisite reading: start at our article and consider getting in touch with your local software development expert.

Nimur (talk) 23:47, 10 January 2019 (UTC)[reply]

But I just want to download some stuff that can be only found at the wip repository and not the main one. I dont want to contribute with code.177.92.128.62 (talk) 10:28, 11 January 2019 (UTC)[reply]

Browse the available tarball snapshots.

The pkgsrc-wip resource is not meant for novice users; it is designed for expert software developers who are already very familiar with creating software on BSD platforms. If that is not a description of you, maybe you should explain what you're really trying to do, so we can avoid an XY problem scenario.

Nimur (talk) 14:42, 11 January 2019 (UTC)[reply]

January 13

cgi-bin

Does the user experience on a website using the Common Gateway Interface differ significantly, in any way, from the user experience on a website not using the interface? I just noticed that cgi-bin is linked from the citation templates of a bunch of non-computing articles, e.g. Broderick County, Kansas Territory uses

"An Act for the Admission of Kansas into the Union" (cgi-bin). Thirty-sixth United States Congress. January 29, 1861. Retrieved November 26, 2007.

As far as I can tell, CGI is just a way of setting up a website, and aside from potential tiny differences in the speed of loading, there doesn't seem to be any noticeable difference if you're just visiting the website. I'm tempted to remove these links, since there's no point to having them (and the link might make someone think it's significant), but of course I don't want to do that if there really is a good reason. Nyttend (talk) 02:41, 13 January 2019 (UTC)[reply]

cgi-bin content is generated at the time of the request and is suitable for dynamic content that could change for each request. For references its use is dubious as a later request may return something different to what the original referencer saw. However some web sites may always return the same content for the same url and then cgi-bin does not hurt. I agree with Nyttend that mentioning it is irrelevant because it is not a file format. (we can mention if the result is .pdf or .ps or .mp3 or other file/document format). Graeme Bartlett (talk) 03:14, 13 January 2019 (UTC)[reply]

January 14

Popularity of LISP in 1989

If you look at TIOBE, scroll down to "very long term history", it says that LISP was the second-most popular programming language in 1989 (and remained quite popular for more than 10 years after that). I can understand why COBOL was #3 in 1999, all of the code that had to be changed for the Y2K problem, but I don't see why LISP was so popular in 1989. Does anyone know? Bubba73 ^{You talkin' to me?} 19:39, 14 January 2019 (UTC)[reply]

Those are quite dubious listings, as they don't explain their methodology, or list all the languages studied. Visual Basic was huge through the 1990s, but they only (in that summary) show the .NET version. BASIC (generically) was still very popular through the '80s. Where's Modula-2? dBase II? Why isn't SQL there long before 1999? They also show Pascal (generically) climbing from 1989 to 1994, yet dropping out by 2000. I presume that's mostly Object Pascal, but Turbo Pascal went much the opposite way - increasingly popular under MS-DOS, but then never recovering its pre-eminence once Windows 3.0+ shipped after 1990.

As to Lisp, then Lisp (and Smalltalk) was talked about a lot in the late '80s, but most people were using 286 PC clones or 68000 workstations if they were lucky, never had enough RAM, and didn't have the performance considered to make it worthwhile. Apart from US universities (MIT being a leader, although mostly with Scheme), one platform that did use a lot of Lisp invisibly was AutoLISP embedded within Autodesk products such as AutoCAD.

I'd be looking at old copies of Byte for a more detailed view of this. Andy Dingley (talk) 20:31, 14 January 2019 (UTC)[reply]

Yes, that Pascal ranking is strange #14, then #3, then #5, then #96, then #14 twice, then #199. Perhaps they split off Delphi and Object Pascal. used to have a lot of Byte magazines, but I got rid of them a few years ago. I used LISP in an AI in the 1980s, and it did take a lot of memory. None of us could run our programs until the professor got our memory limit on the mainframe increased. Bubba73 ^{You talkin' to me?} 21:48, 14 January 2019 (UTC)[reply]

I find the listings at the TIOBE website to be entirely useless, because they implicitly assume that any language is suitable for any task.

For example: the "percentage" of the marketplace who program in VHDL cannot be meaningfully compared the percentage who program in Objective-C or in the "R" programming language. These communities are quite different in demographic, in purpose, and in the type of technical work that the programmer is doing. If somebody recommends that you switch from "R" to "VHDL" on the basis of language-popularity, you should stop taking technical advice from them!

Language "popularity" is a very silly metric; computer languages are not generally "interchangeable" in the context of a practical setting.

A much more useful way to approach this topic is to read about Lisp (and its history) from the perspective of an expert: for example, Peter Norvig's Paradigms of AI Programming retrospective is very informed; John McCarthy's LISP---NOTES ON ITS PAST AND FUTURE is very well-informed; and so on.

These aren't just random junk-links found via an internet search; these guys (Peter Norvig and John McCarthy) are not just random bloggers or casual commentators - they happen to be important figures in the history of the LISP programming language. They have useful perspectives on the language, and its implementations, and the communities who used and modified them. When a world-expert in optimization theory and formal language chooses to apply the words "approximate local optimum in the space of programming languages;" or, "In 1991 Lisp offered a combination of features that could not be found in any other language"... each word in these summaries carries great meaning. These are direct quotes from people who studied (and invented) lots of computer languages.

Nimur (talk) 21:50, 14 January 2019 (UTC)[reply]

the 1980's were the time of Lisp machines and high enthusiasm about AI (before the 1987 AI winter.) Aecho6Ee (talk) 13:55, 15 January 2019 (UTC)[reply]

Yes, but that article says that there were only about 7,000 Lisp machines. Bubba73 ^{You talkin' to me?} 18:41, 15 January 2019 (UTC)[reply]

January 15

Blown-out file sizes

Why some video and image editing programs (including Movavi, Photoshop and free online programs) blow out the file size (compared to the original) even after you trim or crop a video or an image (which in theory reduces its file size)? My understanding is that, contrary to what some programs suggest during retouching, it's impossible to save the edited file in a higher quality that the original. Brandmeister^talk 19:04, 15 January 2019 (UTC)[reply]

I don't know the answer, but the same thing happens to me. Editing a file usually makes it larger. Maybe it has to do with compression. Bubba73 ^{You talkin' to me?} 19:12, 15 January 2019 (UTC)[reply]

Your assumption is not entirely correct.

First, you are mixing quality and file size. They are related, but not you have to consider compression. For example, what if I open a JPG image that was saved at 50% compression and I save it with 0% compression. My file will be much larger because it is using absolutely no compression. I won't increase the quality of the image. I get the image rendered from the 50% compression information. I save my rendered image with no compression. Did I increase quality? Not really. But, I did save more data, which takes more space.

Second, you mentioned editing a file. When you edit a file, you might increase the information required to represent the image. For example, I have an image that is completely one shade of red. That can compress down to a very tiny file. I edit it and write my name across it. Even if I crop the image, it takes more data to save the image that represents my name than it did to just say "it is all red." So, the image with smaller display size requires more disk space.

There are more issues to consider, but I thought those two would be enough to help you think about what exactly is happening. 216.59.42.36 (talk) 19:22, 15 January 2019 (UTC)[reply]