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  • Python in Finance by Yuxing Yan, Packt Publishing Book Review

    - by Compudicted
    Originally posted on: http://geekswithblogs.net/Compudicted/archive/2014/06/04/python-in-finance-by-yuxing-yan-packt-publishing-book-review.aspx I picked Python in Finance from Packt Publishing to review expecting to bore myself with complex algorithms and senseless formulas while seeing little actual Python in action, indeed at 400 pages plus it may seem so. But, it turned out to be quite the opposite. I learned a lot about practical implementations of various Python modules as SciPy, NumPy and several more, I think they empower a developer a lot. No wonder Python is on the track to become a de-facto scientist language of choice! But I am not going to compromise the truth, the book does discuss numerous financial terms, many of them, and this is where the enormous power of this book is coming from: it is like standing on the shoulders of a giant. Python is that giant - flexible and powerful, yet very approachable. The TOC is very detailed thanks to Packt, any one can see what financial algorithms are covered, I am only going to name a few which I had most fun with (though all of them are covered in enough details): Fama*, Fat Tail, ARCH, Monte-Carlo and of course the volatility smile! I am under an impression this book is best suited for students in Finance, especially those who are about to join the workforce, but I suspect the material in this book is very well suited for mature Financists, an investor who has some programming skills and wants to benefit from it, or even a programmer, or a mathematician who already knows Python or any other language, but wants to have fun in Quantitative Finance and earn a few buck! Pure fun, real results, tons of practical insight from reading data from a file to downloading trade data from Yahoo! Lastly, I need to complement Yuxing – he is a talented teacher, this book could not be what it is otherwise. It is a 5 out of 5 product. Disclaimer: I received a  free copy of this book for review purposes from the publisher.

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  • Programming Interactivity de Joshua Noble, critique par verdavaine yan

    Bonjour, Voici ma critique du livre de Joshua Noble Programming Interactivity A Designer's Guide to Processing, Arduino, and openFrameworks Citation: Au travers de son livre Programming Interactivity, Joshua Noble propose un guide pour comprendre et développer différentes interactions avec une machine, que ce soit visuel ou physique. Le public visé est tous niveaux. Pour cela, le guide se repose sur trois frameworks :Processing : basé sur...

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  • Développement d'applications professionnelles avec Android 2 de Reto Meier, critique par verdvaine yan

    Je viens de lire "Développement d'applications professionnelles avec Android 2" de Reto Meier, ingénieur chez Google. [IMG]http://images-eu.amazon.com/images/P/274402452X.08.LZZZZZZZ.jpg[/IMG] Je le trouve très complémentaire aux tutoriaux qu'on trouve sur Internet. Il aborde beaucoup de sujets et le nombre de pages n'est pas dù à des captures d'écrans ! Ce que j'ai particulièremen apprécié, ce sont toutes les petites informations tirées de son expérience qu'il distille au fil des pages. L'avez vous lu ? Si oui, par rapport à d'autres livres sur le sujet ? Allez vous le lire ?...

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  • Substitute values (for specific dates) from a second data frame to the first data frame

    - by user1665355
    I have two time series data frames: The first one: head(df1) : GMT MSCI ACWI DJGlbl Russell 1000 Russell Dev S&P GSCI Industrial S&P GSCI Precious 1999-03-01 -0.7000000 0.2000000 -0.1000000 -1.5000000 -1.0000000 -0.4000000 1999-03-02 -0.5035247 0.0998004 -0.7007007 -0.2030457 0.4040404 -0.3012048 1999-03-03 -0.2024291 0.2991027 0.0000000 -0.6103764 0.1006036 -0.1007049 1999-03-04 0.7099391 0.2982107 1.5120968 -0.1023541 0.5025126 0.4032258 1999-03-05 2.4169184 0.8919722 2.1847071 2.7663934 -1.2000000 0.0000000 1999-03-08 0.3933137 0.3929273 0.5830904 -0.0997009 -0.2024291 1.1044177 tail(df1) : GMT MSCI ACWI DJGlbl Russell 1000 Russell Dev S&P GSCI Industrial S&P GSCI Precious 2011-12-23 0.68241470 0.84790673 0.9441385 0.6116208 0.5822862 -0.2345300 2011-12-26 -0.05213764 0.00000000 0.0000000 0.0000000 0.0000000 0.0000000 2011-12-27 0.20865936 0.05254861 0.3117693 0.2431611 0.0000000 -0.7233273 2011-12-28 -0.62467465 -1.20798319 -1.1655012 -0.9702850 -2.0414381 -2.4043716 2011-12-29 0.52383447 0.47846890 0.8647799 0.5511329 -0.0933126 -1.2504666 2011-12-30 0.26055237 1.03174603 -0.4676539 1.2180268 1.9613948 1.7388017 The second one: head(df2) : GMT MSCI.ACWI DJGlbl Russell.1000 Russell.Dev S.P.GSCI.Industrial S.P.GSCI.Precious 1999-06-01 0.00000000 0.24438520 0.0000000 0 -0.88465521 0.008522842 1999-07-01 0.12630441 0.06755621 0.0000000 0 0.29394697 0.000000000 1999-08-02 0.07441812 0.18922829 0.0000000 0 0.02697299 -0.107155063 1999-09-01 -0.36952701 0.08684107 0.1117509 0 0.24520976 0.000000000 1999-10-01 0.00000000 0.00000000 0.0000000 0 0.00000000 1.941266205 1999-11-01 0.41879925 0.00000000 0.0000000 0 0.00000000 -0.197897901 tail(df2) : GMT MSCI.ACWI DJGlbl Russell.1000 Russell.Dev S.P.GSCI.Industrial S.P.GSCI.Precious 2011-07-01 0.00000000 0.0000000 0.0000000 0.0000000 0.00000000 -0.1141162 2011-08-01 0.00000000 0.0000000 0.0000000 0.0000000 0.02627347 0.0000000 2011-09-01 -0.02470873 0.2977585 -0.0911891 0.6367605 0.00000000 0.2830977 2011-10-03 0.42495188 0.0000000 0.4200743 -0.4420027 -0.41012646 0.0000000 2011-11-01 0.00000000 0.0000000 0.0000000 -0.6597739 0.00000000 0.0000000 2011-12-01 0.50273034 0.0000000 0.0000000 0.6476393 0.00000000 0.0000000 The first df cointains daily observations. The second df contains only the "first day of each month" forecasted values. I would like to substitute the values from the second df into the first one. In other words, the "first day of each month" values in the first df will be substituted for the "first day of each month" values from the second df. I tried to write an lapply loop that substitutes the values and was only trying to use match function. But I failed. I could not find the similar question at StackOverflow either... Greatful for any suggestions!

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  • Please help for change wallpaper on terminal where image from http (ubuntu 12.04)

    - by Yan Fachmi
    I need to change the background of my desktop in Ubuntu 12. 04 with a command in terminal, in order to make a script with bash. Does anyone know how to do it? but i want the image from internet... i know if i use local image would like this : gsettings set org.gnome.desktop.background picture-uri file:///home/icorner/wallpaper/curr.jpg but if i use something like this wont work gsettings set org.gnome.desktop.background picture-uri http://www.sergiuhelldragoon.com/wp-content/uploads/2012/04/dota_2_wallpaper_1_1280x800_by_zadelim.jpg Please anyone or somebody?... Thanks & regards, Yan Fachmi

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  • PHP postgres backup.

    - by russell kinch
    Hi. I am trying to make a Postgres PHP backup script. I have downloaded one for the command line which looks like this: #!/bin/bash find /home/russell/pg_bkp -type f -mtime +7 -exec rm {} \; time=`date +%Y-%m-%d`; # date in reverse so that lastest date appears last in the list of backup files. PGPASSWORD=****** pg_dump -i -h localhost -p 5432 -U postgres -F c -b -v -f "/home/russell/pg_bkp/$time.backup" ah3 How can I implement this in PHP? The extension that this creates is .backup. It works great and have used it many times. the data is perfect, but doing it from inside my website would be better. Thanks

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  • Android NDK - does it support straight ARM code or just Thumb

    - by Russell Kay
    All, I have been asked to evaluate the Android platform for our product and I am looking at various options, I am only just scratching the surface just now and the one thing that is bothering me is that I cannot see how to compile code as straight ARM code (no Thumb), I know that Thumb runs slower and we will need the performance in key sections of our code. I think it should just be setting the -march flag in the LOCAL_CFLAGS of the Android.mk file, but I cannot get that to work... Can anyone help. Russell

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  • Linking to network shares from Sharepoint pages

    - by Russell C
    So the place I work decided to set up a Microsoft Sharepoint 2010 server for task management and I (as the lowly entry-level intern) have been tasked with "figuring it out." One thing that the end users really, really, really, want is the ability to link to network shares (that are readable by anyone who will be using sharepoint) from a Sharepoint web page. In order to do this, I have edited the HTML manually with several lines that look like the following: <a href="file://server/share">Server Share</a> This works (sometimes) but the link reported by Sharepoint is often wrong and editing pages that contain these links will mangle the code such that when I open it, the code no longer looks like what it did when I last hit save (breaking all those links). Obviously this is not sustainable. I've been told by coworkers that "It worked that way at the last place I worked" but I haven't found out how yet. Any ideas on how this would work or am I barking up the wrong tree? None of the knowledge searches I've done shed any light on the sitataion. Thanks for any help! -Russell P.S. It should be noted that the file option in an href tag ONLY works in IE (which is a real bummer since we mostly use Firefox).

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  • What encoding I should use in editor (NetBeans), if I were intend to print non-english character

    - by Yan Cheng CHEOK
    I try to set the encoding of my editor to UTF-16. (Java String store the data in UTF-16 internally, right?) And I type the following code package helloworld; /** * * @author yan-cheng.cheok */ public class Main { /** * @param args the command line arguments */ public static void main(String[] args) { // TODO code application logic here System.out.println("???"); System.out.println("\u6587\u4EF6\u79CD\u7C7B"); } } However, the output is not what I expected : ???? ????? I try to change the editor encoding format to UTF-8, it works this time! ??? ???? May I know why I need to change the editor encoding format to UTF-8 but not UTF-16? Isn't Java String store the data in UTF-16 internally?

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  • CATiledLayer: Determining levelsOfDetail when in drawLayer

    - by Russell Quinn
    I have a CATiledLayer inside a UIScrollView and all is working fine. Now I want to add support for showing different tiles for three levels of zooming. I have set levelsOfDetail to 3 and my tile size is 300 x 300. This means I need to provide three sets of tiles (I'm supplying PNGs) to cover: 300 x 300, 600 x 600 and 1200 x 1200. My problem is that inside "(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx" I cannot work out which levelOfDetail is currently being drawn. I can retrieve the bounds currently required by using CGContextGetClipBoundingBox and usually this requests a rect for one of the above sizes, but at layer edges the tiles are usually smaller and therefore this isn't a good method. Basically, if I have set levelsOfDetail to 3, how do I find out if drawLayer is requesting level 1, 2 or 3 when it's called? Thanks, Russell.

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  • iPhone SDK: How to centre content in a UIScrollView during setZoomScale?

    - by Russell Quinn
    I'm using a UIScrollView to show photos. If they are zoomed out so they are smaller than the scroll view in one dimension then the content is centred using contentInset and contentOffset. This all works fine for scrolling and manual zooming. However, if I use setZoomScale (with animated YES) then when zooming out the scroll view sets the top left edge to 0,0 during the animation and then snaps it back afterwards. It seems like the zoom animation ignores the contentInset and contentOffset settings. Does anyone have any idea how to overcome this problem? Thanks, Russell.

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  • Can I use the TFS Object Model to interact with TFS via F#?

    - by Russell
    I am looking for some quick ways to do some (more) complex queries across who has what checked out and things like that (eg. which files have 1 person checked out). I have been learning F# over the last year or so and saw the potential to use both the functional aspects of F# to quickly create some useful and more complex TFS commands. I was wondering if anyone else has done this, or have any ideas on how I would go about doing this. PS: I am using TFS 2005. Thanks Russell

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  • Create Zip File In Windows and Extract Zip File In Linux

    - by Yan Cheng CHEOK
    I had created a zip file (together with directory) under Windows as follow : package sandbox; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.util.zip.ZipEntry; import java.util.zip.ZipOutputStream; /** * * @author yan-cheng.cheok */ public class Main { /** * @param args the command line arguments */ public static void main(String[] args) { // These are the files to include in the ZIP file String[] filenames = new String[]{"MyDirectory" + File.separator + "MyFile.txt"}; // Create a buffer for reading the files byte[] buf = new byte[1024]; try { // Create the ZIP file String outFilename = "outfile.zip"; ZipOutputStream out = new ZipOutputStream(new FileOutputStream(outFilename)); // Compress the files for (int i=0; i<filenames.length; i++) { FileInputStream in = new FileInputStream(filenames[i]); // Add ZIP entry to output stream. out.putNextEntry(new ZipEntry(filenames[i])); // Transfer bytes from the file to the ZIP file int len; while ((len = in.read(buf)) > 0) { out.write(buf, 0, len); } // Complete the entry out.closeEntry(); in.close(); } // Complete the ZIP file out.close(); } catch (IOException e) { e.printStackTrace(); } } } The newly created zip file can be extracted without problem under Windows, by using http://www.exampledepot.com/egs/java.util.zip/GetZip.html However, I realize if I extract the newly created zip file under Linux, using http://www.exampledepot.com/egs/java.util.zip/GetZip.html, I will get a file named "MyDirectory\MyFile.txt" instead of MyFile.txt being placed under folder MyDirectory. I try to solve the problem by changing the zip file creation code to String[] filenames = new String[]{"MyDirectory" + "/" + "MyFile.txt"}; But, is this an eligible solution, by hard-coded the seperator? Will it work under Mac OS? (I do not have a Mac to try out)

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  • Can't run node.js script on server reboot

    - by webstyle
    I need to listen events on port 3240 and I'm using node.js for that purpose. I need to execute my script with forever tool. I also need to run forever on server reboot. When I run forever glh.js everything works: forever list says there is a running process. But when I'm trying to run forever on server reboot I can't get it working. I've created a file in /etc/init.d with the following content: #!/bin/bash /var/www/yan/data/gitlabhook/runglh.sh &>/var/www/yan/data/gitlabhook/runglh.log When I reboot the server, the output log is the following (the same as when I run it manually via console): info: Forever processing file: glh.js But in this case forever doesn't start a process. forever list outputs: info: No forever processes running

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  • How to enable 3D acceleration under VMware workstation 8, Ubuntu 11.10 host, Ubuntu 11.10 guest

    - by Yan Zhou
    I saw there are similar questions, but I don't think they answer exactly my questions. Did anyone managed to get 3D acceleration work under VMWare workstation 8? I have VMware 8.01 installed on Ubuntu 11.10. The guest I am trying is also Ubuntu 11.10. I manually installed vmware-tools and it went well, except the X-config part was skipped as it said the distribution driver is used. The guest runs well but it seems fall back to 2D mode. Does any one has any idea how to enable 3D acceleration under VMWare workstaion with Linux guest?

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  • Implementing a wrapping wire (like the Worms Ninja Rope) in a 2D physics engine

    - by Andrew Russell
    I've been trying out some rope-physics recently, and I've found that the "standard" solution - making a rope from a series of objects strung together with springs or joints - is unsatisfying. Especially when rope swinging is relevant to gameplay. I don't really care about a rope's ability to wrap up or sag (this can be faked for visuals anyway). For gameplay, what is important is the ability for the rope to wrap around the environment and then subsequently unwrap. It doesn't even have to behave like rope - a "wire" made up of straight line segments would do. Here's an illustration: This is very similar to the "Ninja Rope" from the game Worms. Because I'm using a 2D physics engine - my environment is made up of 2D convex polygons. (Specifically I am using SAT in Farseer.) So my question is this: How would you implement the "wrapping" effect? It seems pretty obvious that the wire will be made up of a series of line segments that "split" and "join". And the final (active) segment of that line, where the moving object attaches, will be a fixed-length joint. But what is the maths / algorithm involved for determining when and where the active line segment needs to be split? And when it needs to be joined with the previous segment? (Previously this question also asked about doing this for a dynamic environment - I've decided to split that off into other questions.)

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  • Correct Display configuration. Errors while trying to arrange displays

    - by David Russell Parrish Bojrquez
    I am trying to set up my tv with my laptop trough a VGA cable. The display application in Ubuntu throws a lot of errors to me and I have given up in trying to do it myself. I try to apply the 1920 1080 display. The selected configuration for displays could not be applied Requested size (3200, 1080) exceeds 3D hardware limit (2048, 2048). You must either rearrange the displays so that they fit within a (2048, 2048) square or select the Ubuntu 2D session at login. And Also this: Failed to apply configuration: %s GDBus.Error:org.gtk.GDBus.UnmappedGError.Quark._gnome_2drr_2derror_2dquark.Code3: Requested size (3200, 1080) exceeds 3D hardware limit (2048, 2048). You must either rearrange the displays so that they fit within a (2048, 2048) square or select the Ubuntu 2D session at login. Please Help. @Leozitop No I don't see anything when connected to 1920 1080 because the setup fails before actually applying. Yes there are other resolutions which do work. I believe the problem has something to do with the rotation it is set up. My Ubuntu Display application has only clockwise and counterclockwise options for the TV display. I really don't know why this is happening. Basic procedure: Plug in cable, did not get the resolution I wanted. Changed settings, applied them. Re-peat until desired display is shown. I'm not a computer illiterate, really it baffles me that this is happening. Output of xrandr: david@LapUbuntu:~$ xrandr Screen 0: minimum 320 x 200, current 1880 x 800, maximum 4096 x 4096 LVDS1 connected 1280x800+0+0 (normal left inverted right x axis y axis) 331mm x 207mm 1280x800 60.0*+ 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 VGA1 connected 600x800+1280+0 left (normal left inverted right x axis y axis) 1600mm x 900mm 1920x1080 60.0 + 1280x1024 60.0 1360x768 60.0 1280x720 60.0 1024x768 60.0 800x600 60.3* 640x480 60.0 TV1 unknown connection (normal left inverted right x axis y axis) 848x480 59.9 + 640x480 59.9 + 1024x768 59.9 800x600 59.9 Note that VGA says left and indeed it is, but no other option was available in the display. Also, note the TV1 unknown connection which I have no idea what it is. Note, also, that this has nothing to do with the display since W7 on the computer works fine and since while boot up, and also, before starting session in ubuntu the rotation is normal. I'll also mention that I HAVE re-installed Ubuntu since I had posted this question from a Live CD of 12.04 LTS. And that before the posting of the question also using 12.04 before another backup that I had to do, the VGA setup was fine without any problems.

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  • Virtualbox: host only networking - proxy internet connection

    - by Russell
    I'll ask my question first, then give details about where I am coming from: Is it possible to use host only, then have ubuntu act as a proxy to provide internet access to windows? If so, how? I am trying to get the right combination of networking for my virtualbox windows client VM (win7). My host is ubuntu 10.10 (maverick). I believe I understand the basic network options (please correct me if I am incorrect): NAT - Host can't communicate with guest but guest has access to all host's adapters Host only - Separate adapter but guest has no net access Bridged - bridge an adapter in the host with the virtual adapter to give the host access to the host adapter I am trying to give my win guest internet access, but also access the host in a separate network. Bridged only works when the host is connected to the internet (this is a laptop) so when it's not connected the network is down. Thanks I appreciate your help.

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  • What needs to be done to port a Windows Flash game to Android?

    - by Russell Yan
    My team has developed a game using Flash (with Lua embeded) that targets Windows. And we want to port that game to Android (also iOS in the future). It's acceptable to rewrite the Flash part of client. And some other team in our company recommended Unity3D to replace the Flash part. Since we have no experience in Android/iOS development, we would need to learn some new tool/language anyway. So we would like that learning still be useful after the porting and when we starting a new game. Any thoughts? Edits: I think it is worth noticing the background of the game : the project is started by a tester and developer, both without knowing much about flex and actionscript. They built the game while learning, so most of the code is hard to maintain. I and other two developers joined the project after a year or so when one has leave (and the other be our manager). The other two developers are just graduates with little experience and little knowledge of flex. I am good at the server part and the c# language. Based on the fact that the code is hard to maintain (and we do need to change a lot of code to make the game easier to playe in a mobile device), and I am good at c# (and learning). I still tend to do the porting with Unity, which could get better performance and possibly save time.

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  • What are the options for hosting a small Plone site?

    - by Tina Russell
    I’ve developed a portfolio website for myself using Plone 4, and I’m looking for someplace to host it. Most Plone hosting services seem to focus on large, corporate deployments, but I need something that I can afford on a very limited budget and fits a small, single-admin website. My understanding is that my basic options are thus: I can go with a hosting service that specifically provides Plone. I know of WebFaction, but what others exist? Also, I’d have two stipulations for a Plone hosting service: (a) It needs to use Plone 4, for which I’ve developed my site, and (b) it needs to allow me SSH access to a home directory (including the Plone configuration), so that I may use my custom development eggs and such. I could use a VPS hosting service. What are my options here? Again, I need something cheap and scaled to my level. I could use Amazon EC2 or a similar service (please tell me of any) and pay by the tiniest unit of data. I’m a little scared of this because I have no idea how to do a cost-benefit analysis between this and a regular VPS host. The advantage of this approach would be that I only pay for what I use, making it very scalable, but I don’t know how the overall cost would compare to any VPS host under similar circumstances. What factors enter into the cost of Amazon EC2? What can I expect to pay under either option for regular traffic for a new website? Which one is more desirable for when a rush of visitors drive up my bandwidth bill? One last note: I know Plone isn’t common for websites for individuals, but please don’t try to talk me out of it here; that’s a completely different subject. For now, assume I’m sticking with Plone for good. Also, I have seen the Plone hosting services list on Plone.org—it’s twenty pages long, and the first page was nothing but professional Plone consulting services that sometimes offer hosting for business clients. So, that wasn’t much help. Thank you!

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  • What are the options for hosting a small Plone site? [closed]

    - by Tina Russell
    Possible Duplicate: How to find web hosting that meets my requirements? I’ve developed a portfolio website for myself using Plone 4, and I’m looking for someplace to host it. Most Plone hosting services seem to focus on large, corporate deployments, but I need something that I can afford on a very limited budget and fits a small, single-admin website. My understanding is that my basic options are thus: I can go with a hosting service that specifically provides Plone. I know of WebFaction, but what others exist? Also, I’d have two stipulations for a Plone hosting service: (a) It needs to use Plone 4, for which I’ve developed my site, and (b) it needs to allow me SSH access to a home directory (including the Plone configuration), so that I may use my custom development eggs and such. I could use a VPS hosting service. What are my options here? Again, I need something cheap and scaled to my level. I could use Amazon EC2 or a similar service (please tell me of any) and pay by the tiniest unit of data. I’m a little scared of this because I have no idea how to do a cost-benefit analysis between this and a regular VPS host. The advantage of this approach would be that I only pay for what I use, making it very scalable, but I don’t know how the overall cost would compare to any VPS host under similar circumstances. What factors enter into the cost of Amazon EC2? What can I expect to pay under either option for regular traffic for a new website? Which one is more desirable for when a rush of visitors drive up my bandwidth bill? One last note: I know Plone isn’t common for websites for individuals, but please don’t try to talk me out of it here; that’s a completely different subject. For now, assume I’m sticking with Plone for good. Also, I have seen the Plone hosting services list on Plone.org—it’s twenty pages long, and the first page was nothing but professional Plone consulting services that sometimes offer hosting for business clients. So, that wasn’t much help. Thank you!

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  • How to enable 3D acceleration under VMware workstation 8?

    - by Yan Zhou
    I saw there are similar questions, but I don't think they answer exactly my questions. Did anyone managed to get 3D acceleration work under VMWare workstation 8? I have VMware 8.01 installed on Ubuntu 11.10. The guest I am trying is also Ubuntu 11.10. I manually installed vmware-tools and it went well, except the X-config part was skipped as it said the distribution driver is used. The guest runs well but it seems fall back to 2D mode. Does any one has any idea how to enable 3D acceleration under VMWare workstaion with Linux guest?

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  • Why does Farseer 2.x store temporaries as members and not on the stack? (.NET)

    - by Andrew Russell
    UPDATE: This question refers to Farseer 2.x. The newer 3.x doesn't seem to do this. I'm using Farseer Physics Engine quite extensively at the moment, and I've noticed that it seems to store a lot of temporary value types as members of the class, and not on the stack as one might expect. Here is an example from the Body class: private Vector2 _worldPositionTemp = Vector2.Zero; private Matrix _bodyMatrixTemp = Matrix.Identity; private Matrix _rotationMatrixTemp = Matrix.Identity; private Matrix _translationMatrixTemp = Matrix.Identity; public void GetBodyMatrix(out Matrix bodyMatrix) { Matrix.CreateTranslation(position.X, position.Y, 0, out _translationMatrixTemp); Matrix.CreateRotationZ(rotation, out _rotationMatrixTemp); Matrix.Multiply(ref _rotationMatrixTemp, ref _translationMatrixTemp, out bodyMatrix); } public Vector2 GetWorldPosition(Vector2 localPosition) { GetBodyMatrix(out _bodyMatrixTemp); Vector2.Transform(ref localPosition, ref _bodyMatrixTemp, out _worldPositionTemp); return _worldPositionTemp; } It looks like its a by-hand performance optimisation. But I don't see how this could possibly help performance? (If anything I think it would hurt by making objects much larger).

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  • I cannot search/find any applications in the Dash on 12.04

    - by Russell
    Its been a while since I booted my Ubuntu (12.04), but when i did I had several updates (over 100) and I installed them along with rebooting. These updates seemed to mess with my video driver but I seemed to have fixed this. My problem is that my applications do not show anywhere. I can open them via terminal or if there are shortcuts (such as on the toolbar) but if I hit Super and go to Apps, there is nothing. This is true if I hit Super and search any app name nothing will come back (except for files). I need help to understand what happened! Also for some reason I can't upgrade to 12.10 (I assume because I have 12.04 and not 12.04.1, which I don't understand how to get).

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