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March 6

Calculation

Use the rubric in Addedum B to guide your answers.*A word document that contains the rationale for each of your items.*Your floorplan in Power Point or PDF format.*An Excel document that contains your budget. Consider the following scenario

.Your school received R1 000 000-00 from the Department of education to start an education innovation lab for the school. The aim of the centre is to provide support to teachers who wishes to incorporate educational technology into their teaching and learning. This centre should also be a space where teachers ,researchers and industry could meet in order to advance the use of educational technology for teaching and learning in your province The room for the ICT centre is already established. You need to convert this room into a workable space .The dimensions of the room are 10m X6.

The questions is! You are the leader of the ICT team and therefore responsible for creating the budget for this project. Do the following 2.1Consult the internet and determine the items you need to buy for your ICT centre. List the items you need to buy in your Excel document. 2.2Provide a rationale for purchasing each of items. 2.3Use Microsoft PowerPoint (the shape tool) and draw a floor plan for this center. The plan should the layout of the room 2.4In Microsoft Excel,create a budget for your ICT centre. follow these guidelines

• There should at least be 15 items in your budget ,( complete in question 2.1).
• Create at least three categories for your budget items and sort your items according to these categories for example equipment and furniture .please see the example below.

The following columns should be including in you budget Description of items,2.Total items bought. 3Price per item .4.Total Expense. Best u divide I Total expense of item Total of budget x100

2.5 perform the following  calculations:

Per item:

• Total expense per item
• Total expense weighted percentage per item.

Whole budget

• Calculate the total number of items purchased.
• Average price per item
• Total expenses for all items.

Ensure that the total expense weighted percentage equal a 100% — Preceding unsigned comment added by 41.115.7.158 (talk) 10:39, 6 March 2020 (UTC)

• Please do your own homework. JIP | Talk 12:09, 6 March 2020 (UTC)

Your answer is 5.

Didn't your teacher tell you that Wikipedia is an unreliable source? Elizium23 (talk) 12:11, 6 March 2020 (UTC)

See the article Educational technology for ideas about activities and equipment in the planned room. Consider also how the room may best be used for meetings. One could meet these two situations by moving chairs and tables to create either individual work stations (students facing outward) or a discussion milieu (participants seated around a table). DroneB (talk) 16:24, 6 March 2020 (UTC)

Consider too the infrastructure changes. You may wish to have a store room or secure cupboard to store this valuable equipment. Don't forget extra power points around the room, data and video cabling to connect computers and projectors and screens. The school might also want to spend some on public relations or advertising to get more students/income. Graeme Bartlett (talk) 21:25, 6 March 2020 (UTC)

PR is not considered in the question but it is a reality that an organisation that spends a million South African Rand ( US $63,802 ) will want something impressive to show for it. This alone might suggest emphasizing extra large screen TV(s), interactive whiteboards and language learning stations in advertising the school. DroneB (talk) 23:22, 6 March 2020 (UTC)

March 7

Change Boot Order Priority to SSD, then dvd

How do I make the dvd player load up last and ssd first on a dell laptop? --Thegooduser Life Begins With a Smile :) 🍁 03:47, 7 March 2020 (UTC)

I don't know exactly offhand, without knowing the precise model. However a cold reboot and watching the screen should give you a key to press to enter "BIOS Setup", and then it's usually pretty obvious within that to select the boot order. Andy Dingley (talk) 13:34, 7 March 2020 (UTC)

Yes look for something like Andy says. Sometimes that gets bypassed by default, but there is usually a way to bypass the bypass. Something here might help, e.g. hold down the F2 or F12 key while turning on the power and waiting for the bios to start. 73.93.155.112 (talk) 18:42, 7 March 2020 (UTC)

Other keys to try are Escape and Delete. On some computers you need to repeatedly press the key instead of holding it down. 93.142.81.174 (talk) 23:39, 7 March 2020 (UTC)

Were talking an insprion 5570 I know how to access the bios (sorry for not being very specific) but where do I change the boot order without messing things up? Thegooduser Life Begins With a Smile :) 🍁 23:41, 7 March 2020 (UTC)

You might need to disable Secure Boot first (from this same place), then reboot and go in again. Andy Dingley (talk) 23:55, 7 March 2020 (UTC)

Secure [OFF] Legacy [ON] UEFI [OFF] Should I change it to these settings? Thegooduser Life Begins With a Smile :) 🍁 01:07, 8 March 2020 (UTC)

You generally want UEFI on as it's the modern replacement for the very antiquated BIOS technology (which is what "Legacy" refers to). It's impossible to say exactly what happens for every possible computer, but in general UEFI makes things faster, more convenient, and easier for you. Either way things should work though. --47.146.63.87 (talk) 05:43, 8 March 2020 (UTC)

If you already have an OS installed, there's a fair chance turning off UEFI will prevent your OS from being able to boot up, as it's probably set up for UEFI boot-up and may not have done the necessary for BIOS boot up. Especially if your drive is GPT partitioned. Nil Einne (talk)

OP states UEFI is off, so his OS is most definitely not set for UEFI boot up. It is set for legacy and if legacy is turned off then his OS will fail to boot. Take note that some mobos don't support UEFI and legacy at the same time. If he turns UEFI on, the most likely interesting thing that is going to happen is that he gets confused trying to boot the DVD via UEFI and failing because most bootable CDs/DVDs want legacy mode. This is a mostly useless and potentially dangerous thing to change (tho no lasting damage once you set the correct mode again) unless you're repartitioning the system drive. 93.138.43.92 (talk) 20:16, 9 March 2020 (UTC)

I missed that UEFI as off, although as you say, the same point applies. I wouldn't agree changing to UEFI is useless. I haven't really used CD or DVD boot for a long time so cannot comment on that aspect, but for pretty much anything else, UEFI boot is so much easier to deal with that once you've tried, you probably never ever want to go back to BIOS. That said, if you already have an OS installed, it may not be worth the hassle of changing unless you are reinstalling or otherwise need to modify the boot.

Edit: I was uncomfortable with the DVD/CD think, but since I haven't used one for booting I couldn't safely comment. But thinking about it more, I'm actually fairly unconvinced things are that bad there either. A lot of the time I've created my bootable USBs simply by downloading the ISO, extracting or copying the content to a FAT16 or FAT32 (possibly even FAT12 once) formatted USB drive, and booting. No need to do anything else, or worry about any media creation tool. It simply works since the EFI directory etc are there.

This means the basic structure of the CD or DVD was clearly designed for EFI boot. Perhaps the mainboard UEFI still had problems booting from it from a CD or DVD, but I'm not convinced. I'm also fairly sure I've used EFI with VMs and bootable ISOs too. I'm sure there are a bunch of esoteric Linux, BSD let alone more obscure ISOs which don't support EFI booting, but I suspect the number is dwindling rapidly given their limitations.

I mean I'm sure there are a bunch of mainboards which have weird issues with various issues. But compared to various weird crap you have to put up with while trying to boot from BIOS I'm fairly sure it's a lot less. (It is true that most of the weirdness comes from USB or SATA etc hard disks or floppy disks, and it's not something you encounter so much with CDs or DVDs unless someone screwed up when making them. Still dealing with CDs and DVDs has too many annoyances to make up for that IMO.)

Nil Einne (talk) 17:34, 11 March 2020 (UTC)

The only thing you can "mess up" is making it look for the operating system on the DVD drive first, in which case you just reboot, go back in, and fix your mistake. The computer won't catch fire and explode. I know a lot of non-"computer people" seem to be scared of touching settings like this, but they're usually designed to be pretty straightforward. You usually have to really work at it to mess things up in some way that's difficult to undo. --47.146.63.87 (talk) 05:43, 8 March 2020 (UTC)

• Although I lost my favourite laptop at Christmas and it (forensically) appears as if an unexplained BIOS change to a CPU clock multiplier has turned into a real Halt and Catch Fire instruction 8-( Andy Dingley (talk) 10:53, 8 March 2020 (UTC)

Huh, most CPUs these days except for the models specifically for overclockers have a locked multiplier, meaning it can't be changed. Is the laptop older? Is it just totally dead? If it powers on and at least lets you get into the BIOS, you might just need to reset the BIOS to an older version. Also this is why it's often best to not bother installing a BIOS/UEFI upgrade unless it's really necessary. --47.146.63.87 (talk) 00:59, 9 March 2020 (UTC)

• Haven't had the time to investigate. The motherboard is designed for a long production life, with a range of CPUs in it, so the multipliers are configurable, although probably not the most obvious setting. It appeared to be an overheat fault from the usual "time to clean out the fan" cause and running it on battery (which gives a lower multiplier) didn't show the same problem. To get it working again I just swapped the HD into a duplicate chassis, although this is slightly older, has a lower rated CPU and a lower multiplier. It also runs several degrees cooler, just by the leg temperature! Andy Dingley (talk) 10:39, 10 March 2020 (UTC)

I am a computer technician myself, I was just asking here to make sure I was doing it right :) Thegooduser Life Begins With a Smile :) 🍁 01:07, 9 March 2020 (UTC)

Andy Dingley: I think the number of modern mainboards which cannot handle multiple different CPUs with different multiplier is close to zero. Especially given things like Turbo and Speedstep/Cool and Quiet. However 47 is correct that most CPUs for a long time have had locked multipliers and will not allow overclocking via the multiplier. Since the introduction of Speedstep/Cool and Quiet, these have only locked upwards, but that's not relevant here. There are special CPUs sold for overclocking without locked multipliers but you are unlikely to encounter these on a laptop, especially not a commercial one. Turbo has confused things a bit, but still not that much. Other than a few other exceptions or bugs, it doesn't matter what your mainboard is. Believe me, people have often tried hard to find some way to overclock using increased multipliers. (With good ratios and the end of the FSB etc, overclocking using the core clock is a lot less problematic than it once was. But unlocked multipliers is still an advantage hence the special CPUs etc.) In addition, it's IMO quite difficult to permanently kill a CPU simply by using the wrong multiplier for a short time. Even with the wrong core clock is difficult. The wrong voltage has a far greater chance, although even then you often have to go to extremes IMO. Minor damage over long time, may be a different issue. Nil Einne (talk) 09:39, 11 March 2020 (UTC)

March 8

Very quicksort

= Hi, this is not about any original research as I do rmb I have read about it on web, something year 2005 =

hi ,I think i was able to read about a variant of quicksort that got the worst time consuming of only 2*N*log(N) , by calculating the pivot (for lets first say an array of longint) by the formula pivot= int ((min+max)/2) where min and max are the minimum and maximum values of curent partition and the recursion ended when min=max, for the current one partition. I guess that it could be adapted for others data type than longint, with just a lil bit of extra care. I am saying all this bcz at some brief check on wiki, i got still O(N^2) worst time for qsort. thank You, hope i didnt cause too much bother about this . Yours respectfully, Florin Matei Florin747 (talk) 11:13, 8 March 2020 (UTC)

Quicksort pretty much always has a worst time of O(n^2), using clever pivot selection just makes actually hitting the worst time on real data sets much much much less likely. Picking the median of three (first, mid, and last item) will usually get nearly O(n*log(n)) time but it's entirely possible to run into (or deliberately create) a dataset that thwarts that (which is why it's frequently recommended to select the pivot randomly if security is a concern). 108.29.123.212 (talk) 14:19, 8 March 2020 (UTC)

Funnily enough I was thinking about this this morning. What the IP says above is pretty much spot on, barring some constraint on the data set. Perl changed the behaviour of its hashes for a variant of precisely the security issue mentioned. All the best: Rich Farmbrough (the apparently calm and reasonable) 21:27, 8 March 2020 (UTC).

Alrite, thank You for wasting Your time for processing my little nonsense, I wish to add that, probabily, the idea that i put above may look something like the variant for HHL implementations of the binary sort. I understand that there can be other reasons too, other than the optimizations. Thank You, very useful , in did. Yours respectfully, Florin747 (talk) 07:56, 9 March 2020 (UTC)

You can guarantee O(n log n) by choosing the actual median as the pivot, and you can find the median in O(n) time. See median of medians. 73.93.153.132 (talk) 11:01, 9 March 2020 (UTC)

Thank You for reminding me that! For the moment, due to my not so good memory, I just wasnt able to get that into my memory. Thank You , once again, for Your patience and for Your welness that You are showing to me!

Florin747 (talk) 11:37, 9 March 2020 (UTC)

...Computing Sum(N)=1+2+3+...+N can be try without using formulas, by reducing Sum(2*N) to computing first Sum(1*N), wasting polynomial time. We could try that for Sum1(N)=1*1+2*2+3*3+...+N*N. The interesting point I would like to mention is that we might be able to compute Sum(N*N) by directly aplying Sum(N) for the Sum(N*N)=1+2+3+...+N*N, maybe for more complicated sums either. Sometimes these kinda ideas could be seen as some polynomizations like ideas that could work for EDU purposes. Again, I am not so sure what could go any wrong for these stuff of mine (too). Thank You! Florin747 (talk) 12:55, 9 March 2020 (UTC)

@Florin747: Calculating a pivot is not always that obvious – for example, what is a mean value between character strings "Chirp" and "Quack"...? (Consider foreign languages, where alphabetic order of diacritic letters is not necessarily reflected by their code point values.) Additionally, some algorithms require the pivot value to be placed at its final position as a side effect of the partitioning routine (see the description of Lomuto's algorithm in our Quicksort article and how it differs from the Hoare's one); then you need a delimiting value present in the array, so you can't devise one, but you need to choose it from the array. That last requirement is most important in the Dutch national flag problem problem – when you expect multiple duplicates of key values, you need to choose one of them (the more frequent, the better) to get the central partition as fat as possible. --CiaPan (talk) 15:02, 9 March 2020 (UTC)

Wow!!! this looks much too complicate for me. lets get back, please, to the point that You are saying "Jump!" and I say "How high, Sir!" . I got much more experience for that one topic, I guess... LOL

Anyway, if You are asking me, I would dare to say that I must agree with that hip-hop that are saying something like that :... saluting all schools, they neva were the way, just check out my books!

Anyway, kind respect from Romania , Florin747 (talk) 15:15, 9 March 2020 (UTC)

Alrite, I do apologise , just in case my stuff above here were any unappropriate to You. In case that You really like my ideas , I think that, IF You really wish that, then You may come with some offer on me, for me be treated of skitzophrenia some better place, I mean more expansive care, western stuff like that. In exchange , I may be able to work/create any better, in the field of the middle grade up to highschool level applied maths.

I am saying that bcz I feel like doing myself a favor and try that too. Thank You, whateva Your choice may be! Florin747 (talk) 07:56, 11 March 2020 (UTC)

...for the Dutch Flag Problem, in case that we wish to try stable sorting, what it came to me was something like a possible combination of sorting of a permutation, and some count sort idea, more as for some start possibilities ideas. we might try ,first, equal numbers for each set of same colour balls. Some ago I tried to formulate something like the Problematic of the Problemistics, basicaly if the problem to be solved is too easy then we can try to complicate it, make it any harder, and if the problem to be solved is too hard, make an easier variant of it.

...for some pivot for array of string items, in the common variant based on ASCII codes of characters, idk, for each byte of any rank, we can try the arithmetical mean (related of only two strings). For more than two strings we might focus on the most significant byte/character ASCII code.

Alrite I guess this is all I can do so far, I mention that I am better at some middle grade and highschool problems rather the ones more complicated than that. Thank You! Florin747 (talk) 12:47, 11 March 2020 (UTC)

Funny letters; what are they?

Facebook just served me an ad that began with the following text:

𝗛𝗲𝗹𝗽𝗶𝗻𝗴 𝗼𝘃𝗲𝗿 𝟭,𝟬𝟬𝟬,𝟬𝟬𝟬 𝗿𝗲𝗮𝗹𝗶𝘇𝗲 𝘁𝗵𝗲𝗶𝗿 𝗽𝗲𝗿𝘀𝗼𝗻𝗮𝗹 𝗵𝗼𝗽𝗲 𝗶𝗻 𝗝𝗲𝘀𝘂𝘀 𝗲𝘃𝗲𝗿𝘆 𝗦𝘂𝗻𝗱𝗮𝘆.

What are these characters? They stay bold no matter what I do; see 𝗵𝗼𝗽𝗲 versus 𝗵𝗼𝗽𝗲, for example. They're distinct from normal characters; if I go to 𝘀, for example, I end up at https://en.wikipedia.org/wiki/𝘀, which isn't the same as S or 𝗦. They're essentially normal letters; if I put one of them into Google, I get the same results as if I look for the lookalike normal letter. I know the percent encoding for 𝗦, gained by mousing over the link in this question; it's %F0%9D%97%A6, and if I tweak the last couple of characters, I can end up at the other 25 capitals or the 26 miniscules. Nyttend (talk) 22:25, 8 March 2020 (UTC)

I copy-pasted them in the "Characters" field at https://r12a.github.io/app-conversion/ and clicked "View in UniView". It says "1D5DB MATHEMATICAL SANS-SERIF BOLD CAPITAL H" and so on. See Mathematical Alphanumeric Symbols. PrimeHunter (talk) 22:56, 8 March 2020 (UTC)

A cheesy way to show the message in boldface without using html markup, resembling an IDN homograph attack. 73.93.153.132 (talk) 11:19, 9 March 2020 (UTC)

I think the important question here is, did it help you realize your personal hope in Jesus? Elizium23 (talk) 11:30, 9 March 2020 (UTC)

By the way, Gucharmap is a nice utility (I use it under MATE) for identifying weird Unicode characters by pasting them. 2601:640:108:A5F5:F823:7F80:84B2:C54D (talk) 04:19, 10 March 2020 (UTC)

I use a nifty Firefox plugin named, believe it or not, Identify Characters. —Tamfang (talk) 07:00, 11 March 2020 (UTC)

Malware/spam

Cleaning out my spam folder on Gmail I started to examine a spurious unsubscribe message. It appeared that clicking either yes or no would email about 30 people. This seemed pointless from the PoV of the sender, although I suppose its a multiplier you would have to trick over 1/30 of the recipients.

Any ideas how this was supposed to work? All the best: Rich Farmbrough (the apparently calm and reasonable) 23:15, 8 March 2020 (UTC).

Were the 30 recipients encoded in the spam message? Would all have received the same e-mail message? Was it identical to the spam message?  --Lambiam 15:12, 9 March 2020 (UTC)

How do you know that it would email 30 people? Do you mean that you got a message with 30 addresses in the To: field? 93.138.43.92 (talk) 20:22, 9 March 2020 (UTC)

Yikes, turn off javascript in emails. Turn it off everywhere if you can. 2601:640:108:A5F5:F823:7F80:84B2:C54D (talk) 05:38, 10 March 2020 (UTC)

Javascript is wholly unnecessary to create a link that emails someone. That's what the mailto: URI scheme is for. Elizium23 (talk) 23:17, 11 March 2020 (UTC)

Those links typically launch a mail client on your desktop. Also, without JS, the mailto url shows in the status line. JS allows the status line to be spoofed. 2601:648:8202:96B0:54D9:2ABB:1EDB:CEE3 (talk) 05:12, 12 March 2020 (UTC)

Doesn't Gmail block Javascript? In attachments, anyway. Elizium23 (talk) 05:21, 12 March 2020 (UTC)

Blocking .js attachments is not the same as blocking Javascript code in your email messages. The second is a much more dangerous thing because .js attachments need to be manually downloaded and started by the victim, while Javascript code can execute immediately when the email is opened. It's best to avoid using webmail and turn off Javascript in your email client. 93.136.43.47 (talk) 04:35, 13 March 2020 (UTC)

Couple things here. There is no way in Gmail settings to disable Javascript. That is why I am fairly confident that they block, or at least filter it, in message bodies. Gmail has a "basic HTML" version that should work without benefit of JavaScript. But if you decided to disable JavaScript in your browser, the default full-featured Gmail web client would malfunction. Elizium23 (talk) 06:09, 13 March 2020 (UTC)

March 12

Moodle Videoconferencing/Lecturing?

Due to current circumstances, we may be forced to move to online lectures for the next few weeks. Our Moodle has some proprietary video conferencing plug-in (I don't know who decides these things, or why), but, oh wonder, the number of licenses is insufficient to move some 300000 students to it in a hurry...

Does anybody know if there is a decent open-source plug-in for Moodle that supports video conferencing/lecturing? Thanks! --Stephan Schulz (talk) 08:33, 12 March 2020 (UTC)

I'm surprised that proprietary plug-in is even allowed under Moodle's GPLv3+ licensing. I've never used Moodle but there appear to be a lot of plugins for it: have you checked for a list or directory? I know that Nextcloud and Jitsi have video chat, so maybe it is possible to use one of those, or transplant code from one of them into Moodle. 2601:648:8202:96B0:54D9:2ABB:1EDB:CEE3 (talk) 10:39, 12 March 2020 (UTC)

Probably not, but that won't be the likely problem. Many organizations avoid security by using a VPN. So, to use Moodle, students likely have to VPN into campus. Does your VPN have the seats and bandwidth to handle an entire campus logging in remotely? Probably not. One university I was at for the last five days (I don't want to name names and shame them) decided to simply extend Spring break by a week because they don't have a VPN to handle the students load and they don't want to pay the money to increase it. So, students get one week less education (or more if they keep extending Spring break). 135.84.167.41 (talk) 12:08, 12 March 2020 (UTC)

Maybe try Skype or Microsoft Teams? Have a look on the http://www.edugeek.net forum for ideas - it's run by school IT techies. --TrogWoolley (talk) 13:23, 12 March 2020 (UTC)

Thanks. I would prefer an Open Source solution - if the university wants to use proprietary software, they can figure it out without my input ;-). --Stephan Schulz (talk) 21:24,

12 March 2020 (UTC)

Stephan, do I understand correctly that you seek to support 300,000 (three hundred thousand) users?

If this is true, free access to the source-code is probably the smallest concern: you will almost surely need a commercial-scale service provider to provision storage-space, server bandwidth, video hosting, and so on. Even if you had the source code for everything, would you and your organization be able to scale up to such a volume?

From this perspective, what would be the real use of free and unrestricted access to the implementation-details and source-code? Most of it is only usable by a commercial entity who is specifically in the business of selling the service of scalability. Free-licensing their technical efforts could help their direct commercial competitors, but it probably could not really help you and your students; you'd still have to shop for a service-provider.

Nimur (talk) 14:50, 13 March 2020 (UTC)

There is a Skype plugin for Moodle. While Skype is free, I can't guarantee that the plugin is free. Assuming that it is, you can install Skype on pretty much anything. 135.84.167.41 (talk) 16:47, 13 March 2020 (UTC)