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

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June 2

Microsoft Excel

Does anyone know if Excel has some type of function to (easily) achieve what I am looking for? Let's say that I have a spreadsheet. I am recording data for 4 people for 7 days of the week. (This is just an example that I am greatly simplifying for purposes of this question.) Therefore, my (example) spreadsheet goes 7 columns across (Sunday, Monday, Tuesday, etc.) ... and it goes 4 rows down (for Person A, Person B, Person C, etc.). So, it basically looks like this.

Name	Sun	Mon	Tue	Wed	Thu	Fri	Sat
Ann	100	78	88	102	98	103	97
Bob	65	88	23	78	91	77	90
Cal	29	44	89	12	11	99	63
Deb	33	77	95	38	72	43	52

Now, after I have completed the spreadsheet --- and entered a ton of data --- I decide that I want to "switch" the rows for columns, and vice versa (the columns for rows) ... so that the spreadsheet looks like this. (For this fake spreadsheet, the numbers here are all fake ... and do not correctly correspond from the first spreadsheet to the second ... I just typed in any values.)

Day	Ann	Bob	Cal	Deb
Sun	100	78	88	102
Mon	65	91	77	90
Tue	12	11	99	63
Wed	33	77	95	52
Thu	83	67	43	12
Fri	34	71	25	88
Sat	71	70	86	28

Does Excel have some easy way to do this switch? Or do I need to construct / design a whole new spreadsheet from scratch? I only know the very basics of Excel -- nothing fancy or intricate -- so please keep answers pretty basic without a lot of foreign concepts / technical jargon. Thanks. (Joseph A. Spadaro (talk) 03:03, 2 June 2009 (UTC))

It has been a long time since I've used Excel, but I remember there being a "Transpose" option somewhere that does exactly this function. A quick search says it's a Paste Special option: Transpose Excel data from rows to columns, or vice versa. --Bavi H (talk) 03:41, 2 June 2009 (UTC)

Try copying the original table, click "paste special" and check the "transpose" checkbox, Excel will paste the values transposed. It should work, unless I misunderstood your problem. 93.108.139.109 (talk) 13:19, 2 June 2009 (UTC)

Thanks to you, both. I was able to transpose the data --- due to your help. Thanks again. (Joseph A. Spadaro (talk) 21:48, 5 June 2009 (UTC))

Cost of Printing

What is the price per page of with regard to ink? Alternatively, how many pages per ml can you print? —Preceding unsigned comment added by 90.194.110.63 (talk) 13:54, 2 June 2009 (UTC)

This all depends on what sort of documents you are printing, and which model of printer. Full-page color photos will take a lot more ink than double-spaced black type (words only). You touch on an interesting question; there are many inkjet printers that are remarkably cheap, which are sold in the hopes that the manufacturer will make money by selling you inkjet cartridges. This link (an ink usage comparison of three printers) claims that if you multiply the ml capacity by the cost of some print cartridges, it appears the manufacturers are selling ink for US$5,000 to US$10,000 per gallon. If you Google "inkjet printing cost" you'll find articles like this one that try to compare laser printers vs. inkjet printers — they looked at a couple of laser printers and worked out that because of the higher cost of inkjet ink, it was about 8 times as expensive to use the inkjet, if you end up printing 40,000 pages. Tempshill (talk) 14:15, 2 June 2009 (UTC)

Say I wanted to print normal A4 with normal word margins, no paragraphs, just pure text, how many pages would I get from a 8ml ink cartridge? —Preceding unsigned comment added by 90.194.110.63 (talk) 14:59, 2 June 2009 (UTC)

This article (http://www.creativepro.com/article/under-the-desktop-getting-a-handle-on-ink-costs) sheds some light. ny156uk (talk) 20:32, 2 June 2009 (UTC)

TCOP depends on:

• The toner or ink coverage per page or the average per job; for color printing you need to know the coverage per color
• The cost per page of other user replaceable items— most laser printer require a drum, transfer unit or waste toner unit
• The cost per page of the printing media; i.e. paper
• The cost of printer maintenance— some printers require that parts are changed on a regular basis, such as the fuser, transfer roller and feed rollers

The hard part is to calculate the coverage. I use a special laser printer to directly measure toner coverage. Without some similar tool, you would have to make a guess. The ISO/IEC standard for monochrome toner cartridge yield uses a page at 5% coverage. Heavier graphics increases the coverage and lowers the yield. ---— Gadget850 (Ed) ^talk 21:09, 2 June 2009 (UTC)

parallel processing..........

I found that in year 2005/2006 January/February Examination,1 of the question is very difficult for me to answer it ... can anyone give some point or information to me??

The question is : "With the aid of a diagram,explain how parallel processing affects the speed of computer processing?"

Hope got someone can help me to solve this question and show me the diagram that related to your information/points... i will feel appreciate to you... hope will get your reply soon... Thank you for viewingBebezaii (talk) 16:59, 2 June 2009 (UTC)

Have you read Parallel computing? There are lots of diagrams in that article. You might want to draw a Speedup plot, which usually shows the number of parallel nodes on the x-axis, and the resulting speedup (1 over the total execution time) for a test program. There are a few possible behaviors. No speedup means that the program is not parallelizable, and will have a flat line on this plot. Linear speedup means that the program is exactly parallelizable, and will have a diagonal line with slope 1. Superlinear or sublinear speedups are also possible, and indicate that the parallelization either created some new work or eliminated some work compared to the sequential program. Nimur (talk) 17:27, 2 June 2009 (UTC)

i now know need what diagram already... but i still confuse with the question... i ask my teacher already... she say need to explain how parallel processing affects the speed of computer processing.. minimum need 4 point with one diagram to support the 4 points... now my problem is dunno what is the point.... can anyone explain to me in the easy way.... or give me the answer and explain why you write the answer like this.. maybe in this way i can understand more easy.. Honestly,I got a presentation on next tuesday about this question.... i very scare now because i have to send my slideshow to my teacher after 2 days.. my time is getting short now... i wish someone can give me a hand to answer this problem.... i will appreciate the kindness people very much... i need done my slide show before this friday.. please help me to pass over my difficulty time at this movement... hope will get your reply soon... Thank you very much!!! —Preceding unsigned comment added by Bebezaii (talk • contribs) 03:33, 3 June 2009 (UTC)

English is not your first language, so let me explain as simply as I can. You know the expression "many hands make light work"? It means the same thing when many CPU's are used to do calculations together. Let's take a simple example - the work a CPU has to do to sort a list of data. Suppose the list contains 1000 rows - easy for one CPU to sort right? Now suppose it contains 1 BILLION rows - much more difficult for one CPU and it probably needs a lot of memory and temporary writes to disk etc. Now break that list down to a few million each and imagine lots of CPU's each doing their own sorts - then merging the list finally. That's the power and speed of parallel (many) computing. Sandman30s (talk) 07:15, 3 June 2009 (UTC)

o... is it means parallel processing affects the speed of computer processing is because it can break down the data into few part so the computer can sort the data easy and used less time to sort it,so the speed to sort the data is more faster than a computer sort the data without using parallel processing...then finally combine all the data to one again is it?? by the way i want to make sure one thing... parallel processing can also write as parallel computing right??is it the same?? i will waiting for your reply... thank you for the information!!

Sorting isn't the best example for parallel computing, since the end result requires a single sort. Perhaps a better example is a render farm. In the case of a render farm, you need to generate the animations for each frame of the movie. Since each task (rendering a frame) is independent of others, you can simply spread out the work across many different computers, and then assemble them together once they've all completed. That's an example of a very simple parallel process. Not all parallel computing is quite a simple as with a render farm (something we like to call Embarrassingly parallel). A lot of parallel programming requires communication between the individual units to proceed to the next step. -- JSBillings 12:25, 3 June 2009 (UTC)

I beg to differ. Oracle uses the merge sort and its sorting of a large number of rows of a table is way faster with parallel processes. Each process sorts a portion of rows and the final result is NOT a sort - it is a merge of the sorted lists, which is where the merge sort algorithm gets its name from. Then the sorted list is written from temporary buffers where all the sorting happened, back into the tables (simplistic comment). I just gave as simple an example as I could think of. Rendering is another I suppose. Sandman30s (talk) 14:01, 3 June 2009 (UTC)

wow.. so many answer?? this make me feel more complicated already... i want to know is it parallel processing = parallel computing?? so that i got more confidence to answer when people ask me is it the same thing when i present it... according to the question(9 marks),it need one diagram(1 marks) and explain it with four point(each point 2 marks)... if you is me,how will u answer the question and what diagram will u get for the answer? i need support now... need to finish my slide show tonight,so please help me to answer tis question if u know how to answer it... honestly,i haven learn anything about parallel processing before... teacher ask us to find answer at internet with myself... now i really in trouble because the time is getting shorter and shorter... PLEASE HELP ME!!! >< please reply me as soon as possible please... Thank you very much!!

Parallel processing is not necessarily parallel computing. You can use time-slicing to get more parallel processes than the number of CPU's on your computer or server - this is "processing" where each "thread" does some work. Parallel computing can mean parallel processing, or using multiple computers to do a complex task. Also check supercomputer on a decades-old debate on vector systems versus massively parallel systems. The current thinking is to go massively parallel. It is common for modern supercomputers to use thousands of processors (not processes) in parallel. Sandman30s (talk) 14:10, 3 June 2009 (UTC)

Again, the original poster should read parallel computing. If that article is too difficult or uses words you don't understand, you can also try the Simple English version. Once you have the very basic concepts from those articles, let us know which points you are having difficulty understanding. Nimur (talk) 14:37, 3 June 2009 (UTC)

the question need a diagram to hlp me explain it... can i use a bar chart(speedup)? —Preceding unsigned comment added by Bebezaii (talk • contribs) 16:16, 3 June 2009 (UTC)

Firewall problems

Upon loading my Desktop PC, desktop is loaded, AVG is up and running etc, after about 2 minutes it pops up that my firewall is not turned on or active and that my PC is at risk(potentially) Its XP SP3 but when i click on the balloon to "resolve" the problem it indicates that windows firewall is already on and running. Is there any reason it doesnt seem to load straight away or am i at any risks as i can run the internet for the 2 minutes before this problem flags up, or even run any non internet programmes. Thanks for any help --CorrectlyContentious 18:10, 2 June 2009 (UTC)

I don't have a solution, or even know if there is a brief exposure, but I have this issue too. --Jc3s5h (talk) 19:25, 2 June 2009 (UTC)

My friend's computer had this symptom too. I downloaded and installed Avast and Spybot, both of which found some problems which the respective programs fixed. On his system, I still need to cleanse a few more stubborn items, but the "firewall not turned on" message seems to have gone away. I'm afraid I don't have the logs available right now to be more specific on the problems found. --LarryMac | Talk 19:44, 2 June 2009 (UTC)

Does the warning pop up again after the first time? If so, run a scan for spyware (Spybot is good). If it's only once, that is a function of Windows not fully recognising AVG as a firewall (it is looking for its own built-in one). Go to My Computer, right click, choose Manage, then choose Services & Applications, Services. Look for "Security Centre". Right click in, choose Properties, then use the drop-down box to Disable it. This will stop the complaint. Naturally, make sure the AVG real-time mode is on.KoolerStill (talk) 22:30, 2 June 2009 (UTC)

I've often seen this happen. The Security Center starts before the Firewall, so the Center freaks out. By the time you go to 'resolve the issue,' the glacially slow human response time has left plenty of time for the firewall to fully start. Washii (talk) 02:18, 5 June 2009 (UTC)

Yes, during the short time that networking is enabled but the firewall isn't running, you're exposed. Which is part of why I personally prefer external hardware firewalls. 199.73.167.244 (talk) 15:09, 5 June 2009 (UTC)

Ubuntu script testing

I have 2 programs on my talk page. I was wondering if some people who have some experience with Aircrack-ng could test this code with their systems. This program works perfikly on my system (My system is Ubuntu 9.04 running Gnome with a Broadcom chipset.) I don't have access to any other wifi cards to test this on. Thank you Smileyhill (talk) 21:33, 2 June 2009 (UTC)

This might not help you but i have ubuntu 8.04 with a wifi card with a braodcom chip. It seems have worked just fine (as in there didnt seem to be any errors, and it correctly reported the key to my wifi network _{all tho it did take 6 hours})– Elliott(Talk|Cont)  15:19, 3 June 2009 (UTC)

Fully automatic Aircrack-ng

This kinda relates to my question here. Thanks to Mr. Anderson's code i have written a program that can automatically start attacking all WEP wifi networks near by, Or can just attack one target. _{Can be found on my talk page}. What i would like to do is to make a live CD that contains this program, I was thinking about modifying a BackTrack live CD but i don't know how to customize a live CD like that. So how would i go about doing this? Smileyhill (talk) 21:16, 2 June 2009 (UTC)

An alternitive that i'd be happy with would be to take an already installed OS and make a live CD with that installed OS's setting / programs and so on. —Preceding unsigned comment added by Smileyhill (talk • contribs) 22:10, 2 June 2009 (UTC)

To answer your question about customized live cds; may i suggest you try Reconstructor. I have no personal experience with that program but it looks like it might do what you want. Or you could try installing it to a USB drive and modify it as you go. – Elliott(Talk|Cont)  16:34, 3 June 2009 (UTC)

Bootable USB is a good option too. You can modify a boot USB easily. One method: Download the Knoppix CD, boot it, insert a USB stick, select "Make Knoppix USB" on the Knoppix menu. --203.202.43.54 (talk) 06:07, 4 June 2009 (UTC)