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May 28

Extracting a graph from a PDF

I have a proposal at

,

and I would like to include the graph on page 5 (the second to the last page) at

to support my argument. I am not much of a PDF wrangler; is there an easy way to extract that page so it can be uploaded to commons?

Optional tweak if it is easy to do: remove the word "persist: from the top line so it reads "Differences in broadband speed".

 • Note: Graphs, charts, and tables aren't considered "original works" and therefore don't meet the requirements for copyright protection. See discussion at Misplaced Pages:Graphics Lab/Illustration workshop/Archive/Mar 2014#Graph of global temperatures, actual vs. predicted..

It seems like there should be a simple way to do this. --Guy Macon (talk) 02:48, 28 May 2015 (UTC)

If you can't find any better method, you could always do a screen grab. One downside is that you are then limited to the resolution of the screen at the time of the grab. Rotating the screen 90 degrees might help a bit, or you could do multiple screen grabs and then stitch them together. You can then edit the pasted screen grab in any bitmap editor, such as MS Paint, which allows you to add text. (If you don't know how to do screen grabs or use MS Paint, just ask.) StuRat (talk) 03:49, 28 May 2015 (UTC)

Another option might be to "print" page 5 to a file, then find a graphics program which can read that in. This would get past the resolution limitation above. StuRat (talk) 03:51, 28 May 2015 (UTC)

I don't think you can upload this to Commons. Your source for the claim that charts are not original works is Hazmat2, who isn't a lawyer as far as I can tell, and who is wrong about this as far as I know. Information as such isn't copyrightable, but layout, color and font choices, and the like are. -- BenRG (talk) 04:42, 28 May 2015 (UTC)

I agree you should seek a second opinion relating to the specific work as it will depend significantly on whether the chart or graph meets the threshold of originality. Of the cases I can find that came up, 2 were kept Commons:Commons:Deletion requests/File:Alleged Luka Magnotta Murder Video View Statistical Data.png, Commons:Commons:Deletion requests/Graphiques SpritMonitor de Vi..Cult... (well multiple images there which interestingly remained tagged as CC licenced although I think the graphs were created by a contributor anyway, it only came up for discussion due to database rights) and 1 was deleted Commons:Commons:Deletion requests/File:Graph of ranks of first ten companies (1992-2013).jpg. Interestingly all these were dealt with by 1 individual, I don't know if that was a coincidence, due to my search terms, or that editor has experience with graph related copyright issues on commons. Nil Einne (talk) 16:07, 28 May 2015 (UTC)

Open the PDF in Inkscape, select page 5 as the one you want to import. Then delete all the stuff on the page you don't want and manipulate it as you like. Then you can save the result as an SVG or PDF, or you can export a region as a PNG. -- Finlay McWalterᚠTalk 07:14, 28 May 2015 (UTC)

I know that the normal reaction to the previous suggestion is "Holy crap on a stick! I can't install a program! I can't open a file! I can't delete anything!" However, this is the best suggestion. Inkscape is free. It does a great job at opening and saving PDF files. You will probably have to ungroup the elements of the file (you will see the ungroup function in the menus). Once you try this, you will be able to alter PDFs with ease. 209.149.115.214 (talk) 12:00, 28 May 2015 (UTC)

If the graphics in question were bitmaps (like photos) then I'd recommend Evince instead. But in this case the histogram isn't a bitmap, but PostScript drawing objects, so Inkscape is the better option. -- Finlay McWalterᚠTalk 14:30, 28 May 2015 (UTC)

I have no problem installing programs (that's what virtualization is for - to remove the fear that a new program will screw everything up) and will try Inkscape.

I will bring up the copyright issue on the appropriate noticeboard and will post a link here. Thanks to all for the examples. --Guy Macon (talk) 19:07, 28 May 2015 (UTC)

Some clients seem to be trying to connect to a password

Some clients seem to be trying to connect to a password. Scanning with airodump-ng I often see stuff like:

 BSSID              STATION            PWR    Rate    Lost  Packets   Probes
 F8:XX:XX:XX:XX:XX  E0:XX:XX:XX:XX:XX    0    0 - 0      7       39   <plausible network name like WLANCOFFEE>,1KNBKJNKJK2788348761,J7b7CPxpxePQ7yCFcjFK
 <router MAC>       <client MAC> ... ... ... .

Those 1KNBKJNKJK2788348761,J7b7CPxpxePQ7yCFcjFK look incredibly close to passwords. Are clients probing for passwords in the mistaken belief that these are networks? Is there an alternative explanation or are people that stupid? --Yppieyei (talk) 15:25, 28 May 2015 (UTC)

Data plan, contract limitations, counting the bites

If a data plan offers x GB for surfing, and y GB for downloading, what do they count as surfing and what do they count as downloading? If I use Skype, will Skype route calls through my device and therefore spend my data quota? Is uploading also counted as downloading? It sounds contradictory, but how can they limit users uploading big files, or seeding torrent files?--Yppieyei (talk) 15:27, 28 May 2015 (UTC)

An ISP can, to a limited degree, differentiate some kinds of traffic from another using packet inspection (particularly the port numbers and related stuff in packet headers) and deep packet inspection on the contents (particularly the protocol-specific header information) of packets. Which kinds of data they chose to put into which billing categories is a function of how they've configured their metering software, and you'd have to ask a specific ISP how that's done. One might imagine that "surfing" means HTTP and "downloading" means streaming and bittorrent - but those aren't technically specific terms, so this doesn't have a general answer. Note that encryption, whether ssh, http-over-ssl, or VPN traffic should be opaque to the ISP's metering inspector, so will all show up as a generic traffic. Unencrypted BitTorrent traffic isn't especially hard to detect. -- Finlay McWalterᚠTalk 16:10, 28 May 2015 (UTC)

Beyond asking them, reading or searching the terms and conditions may provide some clues. Also it's worth remembering that there are still many what most would consider downloads done over HTTP. Nil Einne (talk) 16:13, 28 May 2015 (UTC)

May 29

Steps to get MD5 hash of string?

Hello, how would I calculate an MD5 hash of a string? What steps would I take, and what algorithms are involved? Thanks in advance. —SGA314 (talk) 14:23, 29 May 2015 (UTC)

It is a bit pointless to reinvent this. Most programming languages and database engines have an MD5 function. 209.149.115.214 (talk) 14:40, 29 May 2015 (UTC)

You read the part in our article that MD5 is now considered insecure, right? Rather than creating your own program for scratch, you will most likely find an algorithm included in the standard library of whatever programming language and operating system you prefer. If you state which you use, someone can probably point you to the appropriate library function. Jc3s5h (talk) 14:43, 29 May 2015 (UTC)

I am using VBA (Visual Basic for Applications) which is based on VB6. And No, it does not have a library for doing MD5(Not that I have found anyway). So reinventing this i guess is necessary. Sorry I am using such an old language. —SGA314 (talk) 17:02, 29 May 2015 (UTC)

The solution I would implement, if I was so constrained, is to use Visual Basic for Applications to call into a native library that implements MD5. For example, you can create a wrapper library around the official Windows .NET implementation of MD5, and then you can use VBA to declare the Lib (with a path to the DLL) that implements that feature.

Not all Visual Basic for Applications environments allow you to do this: some are sandboxed (for good reason) and prevent execution of native code.

Even if you can call native code, this is not a great solution altogether: almost every experienced programmer will strongly encourage you to stop relying on such very old (and proprietary) technologies. Microsoft strongly advises you to update to Visual Basic .NET (an environment in which you would not need to link against external libraries). If you still pursue this, it is up to you to find (or create) a library (DLL) that implements the feature you need.

One last alternative is to find (or create) an implementation of the md5 algorithm in VBA. This is not impossible, but it will not be fun.

You should strongly seek to relieve these constraints by switching to a newer incarnation of your technology platform. Microsoft introduced .NET technology for application scripting in 2001, and Microsoft has ceased supporting VBA since 2007. If you pursue a VBA solution, you are, in effect, constraining yourself to a proprietary and obsolete platform.

Nimur (talk) 18:56, 29 May 2015 (UTC)

Yes, I do understand that this is very old and outdated. However, it is a cool little challenge(I like challenging my self). So how would i create a wrapper around the System.Security library? I am using VBA in MS Word 2007(just open word 07 and go to the developer tab and click on Visual Basic button). Now I can't add a reference to the System.Security Dll(I found this in C:\Windows\Microsoft.NET\Framework\v4.0.30319) because every time i try to add a reference it gives me an error saying, "Can't add a reference to the specified file." Any way around this? Or is this a "sandboxed" environment like you were talking about? So worse case scenario I would have to create my own MD5 function. What would be the steps to do so if I can't create a wrapper around an MD5 library? That comes to my second question. What did you mean by, "For example, you can create a wrapper library around the official Windows .NET implementation of MD5, and then you can use VBA to declare the Lib (with a path to the DLL) that implements that feature." So, can you expound on that. What does that entail? Thanks for all of you help so far. I know I am using a very old and unsupported language, but like I said before, I like to challenge my self. I like to push the limits of what a language can do, you know. And if VBA dosen't have a built in MD5 hasher, then I would like to build one. Its just fun for me, whether its hard or not. Thanks, —SGA314 (talk) 19:47, 29 May 2015 (UTC)

So, you're set on the course of using obsolete technology... well, that's fine! But here's another problem: there is no documentation. Take a look at MSDN's website: they do not have any online reference documentation for APIs or programming guidelines for VBA. This technology is a few decades old and has been deprecated since the start of this century.

You're going to have to find the library of some old programmer hoarder who has kept his or her books and CDs from the 1990s if you want API documentation.

I found one website: on external library references for VBA. This isn't a tutorial or a how-to guide: it's a quick reference to jog your memory in case you need to jiggle some bits to make some old system work on a new platform. But you can follow the procedure, and play this puzzle-game to its conclusion, if you want: you're going to need an external library, and you can specify its path using the External References guide. Where is the DLL going to come from? Well, you'll probably have to make it yourself, using modern technology, and cause it to be conformant to the VBA External Objects model (for which we lack free online documentation)!

I think it's great that you're trying to do something just because it's difficult, but there are different types of difficulty in the field of computing. The type you are engaging in is the sort that professional programmers dread - we don't even want to get paid to tackle this kind of problem.

If you want a fun and entertaining problem that is also very difficult, consider writing a from-scratch implementation of MD5, by following the pseudocode described in our algorithm. If you still want to write this in VBA, that would be fine... but it won't make the problem any easier or harder (except that your end result won't be particularly portable!) You would do equally well to program this algorithm in python or C (or even in lisp: it's been done once or twice before)!

Nimur (talk) 21:02, 29 May 2015 (UTC)

Topic was deleted a long time ago by an inactive user.

There was a page that was deleted quite some time ago that may be on a topic I could write about.

The page was LLUCE.

I am the person who wrote LLUCE for the company that was planning on publishing it. There is a reference to it already on the GBBS page, to which I did add some more information, including my name.

I would like to add information on this OS that was supposed to be the successor to ACOS as described however as I was the programmer who wrote it, there is nothing to cite at this point. I am considering placing the program into the Apple ][ portion at archive.com, but would like people to be able to check here so they know what they're looking at.

Andrew Wells — Preceding unsigned comment added by Llandyw (talk • contribs) 23:35, 29 May 2015 (UTC)

Misplaced Pages articles must be supported by reliable and verifiable sources - not Wikia pages, Facebook pages, and personal testimony. The LLUCE and ACOS articles were already deleted for this reason, and I've removed the material you added to GBBS for the same reason. In general, adding content to existing articles, or creating new articles, about yourself or projects with which you are closely associated is usually regarded as a conflict of interest, which that page notes is "strongly discouraged." Frankly, some things (most things) don't belong on Misplaced Pages - they haven't received mainstream coverage and never will, and their memory is much better curated in other sites where whose editorial standards don't require such strict sourcing. -- Finlay McWalterᚠTalk 09:25, 30 May 2015 (UTC)

May 30

Cell phone similar in shape factor to Samsung Galaxy S4 ?

A few weeks back I asked about cell phones that could do digital zooming to allow me to read restaurant menus without using reading glasses. I got one, but wasn't happy with the results (larger but blurrier). So, now I'm looking for cell phones with optical zoom. An actual zoom lens would only come on a very expensive cell phone, but I found a 10x/15x snap-on lens to add to a cell phone that seems to do the trick. It works on my cell phone, but doesn't snap on, since it's designed for another phone (the Samsung Galaxy S4). So, I had to tape it on to do a test. I don't want to pay what the proper model costs, though, so I'm hoping a cheaper model will have similar geometry. These lenses have magnets in them, and snap to the top and left side of the phone. So, the phone must:

1) Have a metallic case that will attract a magnet.

2) Have the same distance from the top, down to the lens (5/8 inch to center of lens).

3) Have the same distance from the left side, to the lens (11/8 inch to center of lens).

4) Have a 1/2 to 3/4 inch corner radius between the top and left side.

So, how can I search for cell phones given these criteria ? StuRat (talk) 04:34, 30 May 2015 (UTC)

@StuRat: The best search tool would probably be here at PhoneArena, it allows you to search by all sorts of dimensions, sizes, shapes, types and OS's. Also, have you taken a look at the Nexus 5? I know it is a bit pricy, but for that you entirely own the phone with no contacts or locks with certain carriers. Hope this helps you out! That search link it quite useful. EoRdE6 21:23, 30 May 2015 (UTC)

Thanks. Looks like I can search by material, so that solves #1, but I can't specify the rest. StuRat (talk) 22:16, 30 May 2015 (UTC)

I'm all in favour of tinkering, especially if you have fun. But coming into the proper age range myself, I can't help to notice (after losing two pairs of optician-made prescription glasses, one on the way to Singapore, and one in Beijing) that I do quite well witch cheap (as in EUR 1.49/pair - 3.99/pair) glasses from the next drugstore. This might not work for everyone, and the solution does lack the high-tech factor. But on the other hand, the glasses never run out of battery, and they give me a nice Mahatma Gandhi/Kurt Gödel/Konstantin Tsiolkovsky retro aspect. --Stephan Schulz (talk) 12:03, 31 May 2015 (UTC)

John Lennon? Contact Basemetal here 12:11, 31 May 2015 (UTC)

Too close to my generation for the retro aspect to kick in - I was born before the Beatles broke up ;-). --Stephan Schulz (talk) 12:21, 31 May 2015 (UTC)

I am seriously nearsighted, and now I hold the menu about 2 inches from my eyes to read it. The drugstore reading glasses don't seem to go to a high enough prescription for me. I have a pair of prescription "coke-bottle" lens glasses. To me, putting those on is no better than holding the menu so close. This is why I want a high tech solution. StuRat (talk) 15:08, 31 May 2015 (UTC)

Is there a site that enable to build and publish app (android) for free?

I looked for such site, I've tried for 4 sites and no one of them enable me to publish it for free149.78.227.97 (talk) 20:56, 30 May 2015 (UTC)

May 31

Desktop issue

I had installed windows 7 in my computer . Recently my desktop is shown black in the start screen. however I can use the right click in desktop and the background image is also shown. I had checked the desktop folder through the explorer and I saw all the folder added to desktop folder there but still all the file are invisible in the main desktop screen. How can I resolve it? AmRit GhiMire "Ranjit" 07:29, 31 May 2015 (UTC)

To me it sounds like you might need to reinstall Windows 7, as one of the files is corrupted. However, as this is a minor problem and a reinstall is a major effort, you might just live with your workaround, instead. StuRat (talk) 15:20, 31 May 2015 (UTC)

If the problem persists after restarting your computer, I would recommend first trying a System Restore (type "System Restore" in the Start menu) to a date before the problem was present, then "repairing" the installation using your Windows 7 installation disc (there should be an option for this after booting from the disc) before reinstalling Windows as a last resort.  — TORTOISEWRATH 20:12, 31 May 2015 (UTC)

How do I figure this ?

# first, set the working directory to the data file location  (this can be easily done in RStudio Menu/Session/Set working directory or by using setwd("~/path to working directory/")) import the ' ' separated .txt files

   0.66 0.34 

 0   2.916667  113.1061   69.54545  27.20455  31.07424  0.4154848   29.23485
 1   4.838235  145.0588   74.58824  33.11765  34.70882  0.5486618   37.69118

# Variable tab the Name given to the two by two Table from the Pima Type Training Set as shown here

# From the two by two in the Training Set Table of those with Diabetes and those Without, add              # Row One Column Two to Row Two Column one, then divide by Total Number of Women, to get #  the Training Error for the Linear Discriminant Analysis Model

   bmi + ped + age, data = pima, model = lda, predict = mypredict.lda, 
   estimator = "cv", est.para = control.errorest(k = 199))
   199-fold cross-validation estimator of misclassification error 

   Null deviance: 256.41  on 199  degrees of freedom

          0.66 0.34 

          0   2.916667 113.1061 69.54545  27.20455 31.07424  0.4154848  29.23485
          1   4.838235 145.0588 74.58824  33.11765 34.70882  0.5486618  37.69118

   bmi + ped + age, data = pima, model = qda, predict = mypredict.qda, 
   estimator = "cv", est.para = control.errorest(k = 199))

Laptop graphics card upgrade

Is there any way I can upgrade the dedicated graphics card on my laptop?

Currently it is an ATI mobility radeon HD 3430, but the performance is lacklustre to say the least, especially at native 1650x1024. — Preceding unsigned comment added by 88.173.224.238 (talk) 11:11, 31 May 2015 (UTC)

While it may not be strictly impossible, it's very unlikely to be practically and economically feasible. Modern laptops are very tightly designed, both from a space and from a temperature/power point of view, and usually have few easily upgradable parts except for memory and mass storage. --Stephan Schulz (talk) 11:48, 31 May 2015 (UTC)

Agreed. Just opening it up is likely to break something. My suggestion, buy a new laptop and use the current one as a backup. StuRat (talk) 15:22, 31 May 2015 (UTC)

Many parts of many laptops are replaceable. I've replaced the LCD panel, keyboard, and fan/heat sink of my Thinkpad T40, which is now 11 years old and still a fine machine (2004 was roughly when CPU speeds flatlined). The laptops are designed to be disassembled in the field, and IBM/Lenovo provide detailed instructions about how to do it. But I don't think the CPU and GPU (graphics card) can be replaced, much less upgraded.

Of course, the original poster's laptop could be one of those ones where everything is soldered in place, even the RAM and hard drive. -- BenRG (talk) 19:37, 31 May 2015 (UTC)

Well, the release date of the ATI mobility radeon HD 3430 was 2008. That's closer to your 2004 laptop than to todays very densely packaged laptops. On the other hand, 2008 was also the release date of the MacBook Air. And my experience tells me that no, CPU speeds did not flatline in 2004. See Megahertz Myth. --Stephan Schulz (talk) 20:05, 31 May 2015 (UTC)

Indeed. Without knowing the model of the laptop it will be hard to assess its upgradeability.  — TORTOISEWRATH 20:09, 31 May 2015 (UTC)

Thanks, and I just wanted to add that it's an HP Compaq 6830s. And yes, I have also taken the whole thing apart screw by screw, bit by bit and I ended up with more screws than I remember starting with so certainly not worried about having another go. I just don't know if it's as easy as hot swapping the graphics board with another of the same series (3xxx)

Are parts like graphics card standardized? I would buy a broken 2nd laptop and break it for the card if I had to. — Preceding unsigned comment added by 88.173.224.238 (talk) 20:23, 31 May 2015 (UTC)

Graphics cards are standardized for desktops, but not really for laptops. A few high-end laptops have replaceable GPUs using MXM cards, but in most, they're built into the motherboard. And the motherboard designs are usually specific to a few similar laptop models. If there were multiple graphics options for the same model of laptop, you might be able to find a replacement motherboard with a better graphics card (and hopefully still find drivers for it), but it likely wouldn't be a huge improvement and would probably be fairly expensive.

Facebook "Photos of" broken?

I don't know if this is the right place to ask about Facebook, but recently I've been unable to view the "Photos of" section of just about any public Facebook page or group. The section for the page or group's own photos works all OK. The "Photos of" section just shows up empty. Is this happening to anyone else? JIP | Talk 19:26, 31 May 2015 (UTC)

looking for quiz generator

Hi there, I look for a quiz generator which has a users system,
and has some AI features, including learning which questions did the student get wrong and re-ask him.
The system needs to have a restrictions system, or a permission system, that monitors that only allowed users are able to use part of the questions.
The system must be written in php.
We're talking about web.
The system should be freeware.
Thanks. — Preceding unsigned comment added by Exx8 (talk • contribs) 19:33, 31 May 2015 (UTC)

Image scanner or digital camera

If you took care of all the details to obtain a photo of quality, could it reach the same level of quality as an image scanner? The article image scanner considers that digital cameras generate lower quality images. However, all problems named there ("a camera image is subject to a degree of distortion, reflections, shadows, low contrast, and blur due to camera shake (reduced in cameras with image stabilisation)") could be dealt with by an experienced photograph. Specially the last point could be better tackled with a tripod and not with image stabilization as claimed in the article. The article seems to be comparing a high-end scanner to a spontaneous photography, done with a pocket camera. --Llaanngg (talk) 20:31, 31 May 2015 (UTC)

Read: Scanning Backs. How they work--Aspro (talk) 20:54, 31 May 2015 (UTC)

Ah. As always... Misplaced Pages has an article Digital scan back. My old flat-bed scanner has far more capacity that the latest digital camera.--Aspro (talk) 20:59, 31 May 2015 (UTC)

How can I contact LinkedIn and get them to clean up the mess they've made?

A few days ago I established an accound on LinkedIn. My level of interest in having such an account was such that I'd have called off the whole thing for fifty cents. LinkedIn caused invitations to be sent to everyone I've ever exchanged email with on gmail. I would have disapproved that if it had been submitted for my approval. My communications with some people via gmail are delicate and this could have serious consequences. I wish to know:

• How can I contact a person at LinkedIn responsible for fulfilling that organization's responsibilities?
• Is there a quick way to get my account closed?
• Would closing it now preclude setting up a new one?

Michael Hardy (talk) 21:14, 31 May 2015 (UTC)

Oh dear, Oh dear. You must be older than 14 then. Try starting here: Managing Account Settings. Next time don't open an account without the guidance of a grandchild who will guide you through the information jungle (where you are the quarry).--Aspro (talk) 21:36, 31 May 2015 (UTC)

You would have had to opt-out of this "email hijacking for spamming all your contacts thing." As it appears, Linkedin makes getting the authorization a feature by default of the registration process, and many users, like you, do not realize that all their friends, co-workers, clients, relatives, and former contacts, are receiving emails from LinkedIn from now on. Go to Your name -> Settings -> Groups, Companies & Applications > Privacy Controls and disable everything that's too intrusive. LinkedIn won't send just one email per contact, it will send several to try and get more users, if you don't know. Yppieyei (talk) 21:51, 31 May 2015 (UTC)

Formal languages and the empty string

1. Why would we need an empty string? What could you not be able to express if you didn't work with such a concept? 2. Where does it appear, only at the beginning and end, or in a string like 'abcdef' is there an empty string between 'a' and 'b', 'b' and 'c' and so on? --Yppieyei (talk) 22:13, 31 May 2015 (UTC)

If the program asked the user to supply a string and the user merely press the enter/return key then the string returned to the program is an empty string. If there is no concept of empty string, how do you describe what the string the user gave the program? 175.45.116.105 (talk) 03:57, 1 June 2015 (UTC)

That's in the wrong direction. An empty string in programming is a string were the terminal character appears right away. The question is about an empty string in formal languages. --Llaanngg (talk) 12:08, 1 June 2015 (UTC)

1. I suppose it's easier on balance (requires fewer special cases) to treat ϵ as a string than not. If a language recognizer's initial state is also an accepting state, it's natural to say that it accepts the empty string; it would be odd to say that you have to leave and reenter that state before it counts, because that's otherwise never true of accepting states. The empty string is a valid program in many programming languages. 2. If "S appears between c and d in T" means that cSd is a substring of T, then yes, ϵ appears between every two characters. -- BenRG (talk) 04:44, 1 June 2015 (UTC)

You don't need it. And we don't need 0. The Greeks even developed a big chunk of their maths without a concept of 0. However, having such elements at hand makes more easy to define certain properties of elements. --Llaanngg (talk) 12:08, 1 June 2015 (UTC)

June 1

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