Wikipedia:Reference desk/Archives/Computing/2011 August 27

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August 27

Reading PDFs that have columns

(I searched the Archives for this topic and got 100s of hits. I hope someone can point me to an answer.)

Reading a two column PDF document with Foxit Reader is very fiddly. Scroll down left col, move up to top of page, move to right side of page, scroll down right col, jump to next page, jump to left side, continue over & over & over. (I can view two column widths but the font size is too small for comfortable reading.)

The mechanics of moving the view area are a major distraction from the actual reading. I have done this many times but it struck me today that there must be a program for reading PDFs that would not require moving between left and right columns.

Is there such a program? Or is there a better way of using the program I am using?

Thanks, Wanderer57 (talk) 00:25, 27 August 2011 (UTC)

Preview, on the Mac, with a Magic Trackpad, is very convenient. Just slide your hands around, and the PDF display similarly slides around.

On iPad, you can double-tap to zoom in to content areas. When you are done reading, just unzoom to see the full document.

If you're committed to reformatting your document, PDF is not really the best file format; reflowable documents like a Microsoft Word document or an HTML file allow the layout-engine to dynamically reflow text. PDFs are intended to deny you this capability, because they are supposed to mimic paper-printouts. Nimur (talk) 03:33, 27 August 2011 (UTC)

Thank you. Just to clarify, PDF is not my "choice" but it is okay for reading single column PDF documents.

I just tried something which seemed to come close to doing what I would like to have happen. I selected a block of text (which can be the whole document),and pasted it into Microsoft Word. The text appears in single column format (good) but each line in the initial text is treated as a separate paragraph (bad) and all spaces between words are lost (very bad).

I wonder about the value of a copy/paste function that loses the separation between words. Maybe from the POV of the developer this is a feature rather than a flaw? Wanderer57 (talk) 12:54, 27 August 2011 (UTC)

It has to do with how PDFs store text. They don't store it as coherent text flows the way that word processors do; they see them more as masses of characters. It's part of the prioritization of making sure everything looks identical on every computer system. It's one of the down sides of using PDFs in this way. --Mr.98 (talk) 13:16, 27 August 2011 (UTC)

In Adobe Reader, you can use View → Zoom → Reflow to reformat multiple columns into one column. It works with plain column layouts, but has more difficulty with complex layouts. Perhaps Foxit Reader also has a Reflow command? --Bavi H (talk) 14:35, 27 August 2011 (UTC)

Thanks. I tried the Adobe Reader Reflow. It works. However when the font size is enlarged, the letters crowd together, giving the same result as in Word. Wanderer57 (talk) 18:46, 27 August 2011 (UTC)

There's also the hand tool, which allows you grab the page and pull it around, and is a lot more convenient than clicking scroll buttons. (Too obvious?) ... and the page up button on the keyboard, for getting back to the top of the page when you reach the foot of a column.  Card Zero  (talk) 13:35, 28 August 2011 (UTC)

Secret Facebook Group

I have created a secret Facebook group for communication between members of a teenage youth organisation of around 20 members. I would love to somehow publish the organisation's future program of events there. Anyone know how to do that? (I know how to add single events, but with a program of, say, 20 special activities over the next 12 months, that would get very clumsy.) So, any ideas please? HiLo48 (talk) 03:38, 27 August 2011 (UTC)

You could list them in a "Doc" (document) on the right side of the page. — Michael J 03:40, 27 August 2011 (UTC)

Yeah, that's worth a try. Thanks. HiLo48 (talk) 04:15, 27 August 2011 (UTC)

(Handy hint from experience using Docs: If you want to leave a blank line between paragraphs, you have to type "space-return". Just hitting return will close up the double-space upon saving.) — Michael J 04:54, 27 August 2011 (UTC)

Are hex codes, CMYK, and RGB equivalent, or does one have greater color range than the rest?

Googling for this gets me lots of tools to convert back and forth, but no answer to my question. It's simple really - do hex codes, CMYK, and RGB colors on the computer describe the same range of color, or is one of those notations more comprehensive than the rest? The Masked Booby (talk) 10:10, 27 August 2011 (UTC)

1. Hex codes are just a way to describe RGB values. RGB can also be specified in decimal notation. You have three channels -- red, green, and blue -- and each usually has eight bits. Eight bits is eight zeros or ones. So, the maximum decimal value of each channel is 255 (or FF in hexadecimal). CMYK is usually described using percentages. You have 0 to 100% of each color.
2. An eight-bit per channel CMYK image will have more colors to work with than an eight-bit per channel RGB image. Why? Because CMYK has four channels, and RGB has only three.

—Best Dog Ever (talk) 10:32, 27 August 2011 (UTC)

When I put hex codes into InkScape it always adds an additional 2 characters for ... saturation? Not sure. That's what prompted me to ask...The Masked Booby (talk) 10:44, 27 August 2011 (UTC)

My recollection is that those extra two codes are for opacity (alpha). --Mr.98 (talk) 13:11, 27 August 2011 (UTC)

Not saturation, alpha value (transparency). An alpha of 255 (xff) is the full colour of that object; of 0 it's the full colour of whatever is underneath it; intermediate values between the two blend together. -- Finlay McWalter ☻ Talk 13:12, 27 August 2011 (UTC)

It's complicated. There are many different color standards called "RGB" and "CMYK". sRGB is the standard RGB color space of the web, modern video cards, and modern monitors. The six-digit hex codes like #89abcd identify sRGB colors; the colors you can represent with those hex codes are the same as the colors your video card can display in "24-bit color" (or "32-bit color") mode. I don't know much about CMYK (subtractive color), but I'm pretty sure most/all CMYK spaces can represent colors outside the sRGB gamut. However, your monitor can't reproduce those colors. You shouldn't necessarily trust any online conversion tools you might have found. I googled "rgb to cmyk" and the first two hits were [1][2]. These sites are worthless, made by people who have no idea what they're doing, and do not actually convert between real RGB and CMYK spaces. -- BenRG (talk) 10:36, 27 August 2011 (UTC)

Gamuts and accurate reproducible colour systems matter very much if you're designing for a medium where the final product will be reproduced with a reliable colour-accurate scheme (like magazine printing or rendering to film stock). But if you're designing for the small (domestic) screen, for a medium like TV or the web, where displays are poorly calibrated and quite divergent in their colour response, there's only so much effort that's worth putting into worrying about accurate colour imaging. Whenever a designer complains to me that object A should be "just a little more green" I drag it over to the other screen of my dual-monitor system (both are decent enough screens, but of a normal office/consumer grade) where she sees the same green isn't the same green at all. -- Finlay McWalter ☻ Talk 13:18, 27 August 2011 (UTC)

Also note that most TVs or monitors can have their color settings changed by the user, at the hardware level and/or with software settings. StuRat (talk) 17:57, 27 August 2011 (UTC)

We have a gamut article that explains this better than any RefDesk answer possibly could, I believe. Looie496 (talk) 17:05, 27 August 2011 (UTC)

What irc channel has the most people in it?

What irc channel has the most people in it? — Preceding unsigned comment added by 173.53.127.9 (talk) 14:15, 27 August 2011 (UTC)

It's been a while since I've 'irced' but I remember that mirc had a channel list function and you could sort that list by the number of people in each channel. Most popular channels vary from server to server. Sandman30s (talk) 08:19, 28 August 2011 (UTC)

My pro-Wikipedia bias wants me to say #wikipedia-en ^connect --Σ _{^talkcontribs} 08:21, 28 August 2011 (UTC)

That only has 150, #python has over 800 people and I've seen other channels go over 1,000 a few times. 82.43.90.90 (talk) 21:22, 28 August 2011 (UTC)

Why is idling in irc channels considered bad?

Why is idling in irc channels considered bad? — Preceding unsigned comment added by 173.53.127.9 (talk) 14:15, 27 August 2011 (UTC)

Is it? I do it all the time, and so do many of my friends.

Must be a social thing among certain groups of people. Where do you learn this? APL (talk) 21:33, 27 August 2011 (UTC)

It's called lurking. And no, I also don't think it's considered bad, depends on what channel I guess. Sometimes having lurkers in a channel can make the more active members feel like having a silent audience which can make them uncomfortable, or it may be that you were supposed to contribute to the discussions but aren't doing so, it may also be frustrating for some to see a full channel and no one talking, etc. Some channels might kick you out, but in my experience, it's perfectly fine. -- Obsidi♠n Soul 21:47, 27 August 2011 (UTC)

How to sync a Palm Tungsten E with a Dell Studio XPS with windows 7 ?

Can a Palm Tungsten E sync with Windows 7? — Preceding unsigned comment added by 24.102.168.98 (talk) 14:47, 27 August 2011 (UTC)

Maybe. --Ouro (blah blah) 11:44, 28 August 2011 (UTC)

Free PDF software

I'm looking for a free online PDF creator and this site is the first hit I got back from Google. On trying to download my computer warned me that files of this type can be harmful. So I'm just wondering if anyone has used this site and if it's safe to download. Cheers TheRetroGuy (talk) 14:51, 27 August 2011 (UTC)

Any executable files you get from the internet can be harmful. That isn't a very strong statement other than saying, "do a little investigation first." Googling for "PDF Creator" (the software in question) turns up a SourceForge project which includes reviews that are a pretty good way to tell you whether it's something you want or not. The reviews are pretty mixed — it seems like it installs some sort of adware or spyware as well. --Mr.98 (talk) 18:36, 27 August 2011 (UTC)

Cheers. Perhaps not such a good idea for me to install it then. I was hoping to get away without having to spend several hundred pounds on Adobe's version, but maybe that's the best thing to do. At least I won't get any unwanted spyware with that. I'll keep looking though before I make a final decision, but having said that, I'd be interested to hear from anyone who has installed a free PDF maker. If there is a reliable one around it would save me a bit of cash. TheRetroGuy (talk) 19:34, 27 August 2011 (UTC)

It's safe to install PDF Creator if you download it from SourceForge. It does have bundled adware, which you can (and obviously should) opt out of during the install. I wouldn't install it (or any software) from random single-page third-party sites like the one you linked, because people have been known to create custom installers for legitimate products that silently install malware at the same time (without giving you a chance to opt out). Legitimate sites are the ones with update logs, previous versions available for download, an active discussion forum, etc. Another way to find the legitimate site is to follow the link from the Wikipedia article. -- BenRG (talk) 20:12, 27 August 2011 (UTC)

CutePDF is probably worth a look. We use it at work (it's free for commercial use as well) and you simply "Print" to a PDF printer and it just works perfectly for what we want.  ZX81  ^talk 19:48, 27 August 2011 (UTC)

Thanks, I'll take a look at that. TheRetroGuy (talk) 19:56, 27 August 2011 (UTC)

Another point just to throw out there is that if you switch to LaTeX for document creation, making PDFs of the output is automatic. I won't kid you though; the buy-in is pretty big. The payoff is also big but only after a high learning burden. --Trovatore (talk) 19:57, 27 August 2011 (UTC)

Cheers. I basically need one to submit a manuscript as they want it in PDF format. Why they can't accept Word is beyond me. TheRetroGuy (talk) 20:01, 27 August 2011 (UTC)

Probably because Word creates an evil, non-documented, proprietary format. And because Word files from different versions are not always compatible with other Word versions. That said, your simplest option is probably to install OpenOffice/LibreOffice, which is as compatible with MS Word as other versions, and which allows you to export to PDF directly. --Stephan Schulz (talk) 20:05, 27 August 2011 (UTC)

Actually newer versions of Word used Office Open XML, which is open, documented, and only mildly malcontent. --Mr.98 (talk) 20:25, 27 August 2011 (UTC)

I don't think that's irrational. Word docs can look different on different machines (for example, if you don't have the same fontset installed, and possibly even just because you're using a different release of Word, though I don't know how far apart they'd have to be before you'd notice that). PDF is more reliably portable — if I understand correctly, the fonts are embedded in the document itself (not sure if that's always true?) and the pagination and margins are completely determined. Another nice thing, though more for you than for them, is that PDF is harder to modify, so unless someone works hard to mess with it, if they show you your document back you can be reasonably confident it's the same way you sent it to them. --Trovatore (talk) 20:07, 27 August 2011 (UTC)

ok, now have OpenOffice downloaded so will mess about with it for a while. I see from the File menu I can export a document in PDF format so hopefully it should give me what I need. Think I might also grab CutePDF. Thanks for all the help and suggestions. Cheers TheRetroGuy (talk) 21:53, 27 August 2011 (UTC)

I'm late to the party but I've also used CutePDF Writer and OpenOffice to create PDF files. I have Office 2010 on one machine here, and although they are also late to the party, Microsoft now supports writing PDF files in Office 2010. Comet Tuttle (talk) 16:07, 28 August 2011 (UTC)

Actually they did in 2007 as well. But it was removed by the default install due to a legal threat from Adobe so you had to download the PDF export seperately. It was added back in one of the service packs I believe. Nil Einne (talk) 17:21, 28 August 2011 (UTC)

I recommend PrimoPDF from personal experience. Rocketshiporion♫ 22:05, 28 August 2011 (UTC)

Maximum RAM capacity for a Compaq presario CM2050 1456VQL1N laptop

I'm trying find out the maximum this computer's hardware allows. I'm tired of searching through forums and would appreciate some kind soul that would throw me a fish. Thanks. 69.243.220.115 (talk) 15:47, 27 August 2011 (UTC)

The best approach for questions like this is usually to connect the computer to www.crucial.com and run their online memory advisor -- it not only tells you the capacity, but what kind of memory will work for you. Other than that all I can say is good luck bwah hah hah hah. (You'll have trouble finding any that works for such an antiquated beast.) Looie496 (talk) 19:01, 27 August 2011 (UTC)

"Additional logon information required" error message Windows 7

I am using Windows 7 (Home Premium) on my laptop. When i connect it to the LAN with RJ 45 connector it shows the error message "Additional log on information may be required". When i open my browser it says "Update your browser" and does not open the site. This happens on all the browser and even though i have the latest versions of each. This problem goes away after waiting for a few minutes. Any ideas?Shraktu (talk) 15:49, 27 August 2011 (UTC)

To get a working internet connection, your computer has to connect (via your modem) to your Internet Service Provider, and be accepted as a valid client. That connection process is where the difficulty is occurring, but the solution to the problem may be specific to the internet provider you are using (which you haven't told us). Looie496 (talk) 18:47, 27 August 2011 (UTC)

It sounds like it might be trying to do a network login, where, instead of running things locally on your computer, it tries to load them over the network (then eventually gives up and does run them locally). So, if there's a way to turn that option off, I'd try that. StuRat (talk) 07:39, 28 August 2011 (UTC)

This sounds similar to some public WiFi networks that require you to log in before you can browse websites. If you connect to a network like this, any address you enter in your browser will take you to the log in page.

See Windows 7 Network Awareness. When you connect to a WiFi network (and I guess also when you plug in an Ethernet cable), Windows checks a specific Microsoft website as a test. If it doesn't get the expected response, it thinks you might be connected to a network that prompts you for a log in. That's why it shows the message "Additional log on information may be required."

In your case, it sounds like something is redirecting any website address you enter to a message asking you to update your browser. This redirection may be caused by your ISP or by your router. Or if you have manually configured DNS server addresses, it may be caused by your DNS provider. On the "Update your browser" page, look for any logos or company names. That might provide a clue who is doing the redirection. --Bavi H (talk) 18:06, 28 August 2011 (UTC)

I think you're referring to a captive portal. I had a ADSL router modem that had a captive portal that showed up when the modem was having problems logging on but also showed up when the modem had just been started and hadn't yet managed to log on, perhaps that's what the OP is referring to. Nil Einne (talk) 18:28, 28 August 2011 (UTC)

Resolved

Shraktu (talk) 04:42, 25 April 2012 (UTC)

Mozilla support forums - few messages since August 18

I read two Mozilla newsgroup support forums mozilla.support.thunderbird and mozilla.support.firefox. Up through August 18 there were several messages per day but only a trickle since then, and one of them was asking why there are no new messages. Has something changed about the Mozilla support newsgroups that would cause me to not get new messages? Bubba73 ^{You talkin' to me?} 21:06, 27 August 2011 (UTC)

Resolved

Bubba73 ^{You talkin' to me?} 02:12, 29 August 2011 (UTC)

select count vs. mysql_num_rows

I have been testing this and I want to ensure this isn't an anomaly on my box. I have a MySQL database table with about 2 million rows. I want to know how many records meet a certain criteria. I have two options. I can use a "select count(*)" query that returns the count -or- I can use a "select id from" query that selects all the ID's that match and use mysql_num_rows to count how many records the query matched. In my test, select count is much faster than mysql_num_rows. However, I've been told that they should be the same. Can anyone else verify if my results are correct or not? -- kainaw™ 23:55, 27 August 2011 (UTC)

I've not done any testing of this, but I would personally expect select count to ALWAYS be faster. That way the server simply calculates the total rows, end of story. The other way it has to actually gather up all the data and generate a recordset for the client only then to be told to get the row count instead of looking at the actual data. The speed difference is going to be down to the amount of data and the speed of the hardware, but I can't see select count ever being slower.  ZX81  ^talk 01:57, 28 August 2011 (UTC)

Agreed. StuRat (talk) 07:00, 28 August 2011 (UTC)

This page suggests that MySQL caches the row counts in tables, which is why count(*) is so fast. I don't know if that's true, but it would make sense if it was. --Mr.98 (talk) 02:09, 28 August 2011 (UTC)

Thanks. -- kainaw™ 11:57, 28 August 2011 (UTC)