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  • Sending keyboard commands to Ubuntu through Python. Remote for my Blackberry

    - by Rudi Strydom
    I am trying to build a remote control application to control media on my Ubuntu. Does anyone know a way in order to accomplish this. The media keys in particular. Thank you. EDIT 1: I have tried using XTE, but is seems python in truncating the input or there is a limit or something which means that you can't do Ctrl + Key key presses, which wont suit my needs. I also tried uinput, but alas you need to run it as root, which also will not quite my needs. Now I am looking at EVDEV which seems promicing, that is if I can get it working.

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  • Perl numerical sorting: how to ignore leading alpha character [migrated]

    - by Luke Sheppard
    I have a 1,660 row array like this: ... H00504 H00085 H00181 H00500 H00103 H00007 H00890 H08793 H94316 H00217 ... And the leading character never changes. It is always "H" then five digits. But when I do what I believe is a numerical sort in Perl, I'm getting strange results. Some segments are sorted in order, but then a different segment starts up. Here is a segment after sorting: ... H01578 H01579 H01580 H01581 H01582 H01583 H01584 H00536 H00537 H00538 H01585 H01586 H01587 H01588 H01589 H01590 ... What I'm trying is this: my @sorted_array = sort {$a <=> $b} @raw_array; But obviously it is not working. Anyone know why?

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  • Problem mounting USB Mobile Broadband dongle in Ubuntu 13.04

    - by Still A Learner
    I have been using Ubuntu 13.04 since last two months and I have problem mounting my USB dongle. I have Lenovo G-580 series laptop. It has 3 USB ports which are 3.0. When I attach dongle to one of the three USB ports the device gets mounted immediately but in the other two ports I have to reboot the OS while the dongle is attached to the laptop in order to mount it and connect to the internet. My dongle is of ZTE. I don't get what is going wrong.

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  • Presenting at SQL Saturday #70 - Columbia SC

    - by andyleonard
    Introduction I'm honored to be presenting at SQL Saturday #70 in Coumbia SC 19 Mar 2011! Its always good to travel to places where I don't have to suppress my accent (what accent? I talk normal. Everyone else sounds funny...) and repeat my order at Waffle House . It's always an honor to hang out with The Keeper of the Duck (K. Brian Kelley) ( Blog | @kbriankelley ) and the cool crew in Columbia. Presentations There are some stellar presentations from awesome speakers scheduled for the event... plus...(read more)

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  • Rendering Unity across multiple monitors

    - by N0xus
    At the moment I am trying to get unity to run across 2 monitors. I've done some research and know that this is, strictly, possible. There is a workaround where you basically have to fluff your window size in order to get unity to render across both monitors. What I've done is create a new custom screen resolution that takes in the width of both of my monitors, as seen in the following image, its the 3840 x 1080: How ever, when I go to run my unity game exe that size isn't available. All I get is the following: My custom size should be at the very bottom, but isn't. Is there something I haven't done, or missed, that will get unity to take in my custom screen size when it comes to running my game through its exe? Oddly enough, inside the unity editor, my custom screen size is picked up and I can have it set to that in my game window: Is there something that I have forgotten to do when I build and run the game from the file menu? Has someone ever beaten this issue before?

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  • bash script to login to webpage

    - by Nathan Cazell
    I am trying to login into this page but I cannot for the life of me get it to work. I have to login to this site when i connect to my school's wifi in order to start a session. So far ive tried to use bash and cUrl to achieve this but have only achieved to give myself a headache. will cUrl work or am I on the wrong track? Any help is greatly appreciated! Thanks, N Here's what i tried: curl --cookie-jar cjar --output /dev/null http://campus.fsu.edu/webapps/login/ curl --cookie cjar --cookie-jar cjar \ --data 'username=foo' \ --data 'password=bar' \ --data 'service=http://campus.fsu.edu/webapps/login/' \ --data 'loginurl=http://campus.fsu.edu/webapps/login/bb_bb60/logincas.jsp' \ --location \ --output ~/loginresult.html \ http://campus.fsu.edu/webapps/login/

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  • How to reset settings when Unity won't finish booting?

    - by Emre
    I have a new 12.04 installation and I messed things up after trying to move /home to an NTFS partition, which I later learned was a bad idea. I removed references to the NTFS partition on fstab and created new users on the ext4 / partition. Now I can't get Unity to start up properly for any user. I get the GUI with only three Launch icons (none of which are clickable) and no bar at the top. The keyboard seems to the nonfunctional after I enter my credentials. The interesting thing is that I can boot when I go through recovery mode and select resume. I wonder whether I am creating the new users properly. What is the correct protocol for doing so in order to ensure that they can run Unity?

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  • RDA Health Checks for SOA

    - by ShawnBailey
    What is a health check in RDA? A health check evaluates something in your environment to determine whether a change needs to be considered in order to avoid a problem or optimize fuctionality. Examples of what this 'something' might be are: Configuration Parameters JVM Options Runtime Statistics What have we done for SOA? In the latest release of RDA, 4.30, we have added a Rule Set for SOA called 'Oracle SOA 11g (11.1.1) Post Installation (Generic)'. This Rule Set contains 14 SOA related health checks. These checks were all derived from common issues / solutions we see in support of the SOA product. Many of the recommendations come from the product documentation while others are covered in the SOA Knowledge Base. Our goal is that you will be able to easily identify the areas of concern and understand the guidance available from the output of the Rule Set. Running the health checks for SOA The rules that the checks use are installed with RDA and bundled by product or functional area into what are called 'Rule Sets'. To view the available Rule Sets simply run the command from the RDA home location: rda.cmd (or .sh) -dT hcve This will bring up a list of the available HCVE (Health Check / Verification Engine) Rule Sets. Each Rule Set contains a group of related rules that are used for evalutation and display of results. A rule can be considered synonymous with a single health check and they are assigned an ID, Name and Description that can be seen when they are executed. The Rule Set for SOA is option number 11 and you just enter this selection at the prompt. The Rule Set will then execute to completion. After running an HCVE Rule Set the tool will write the output to the RDA_HOME/output folder. The simplest way to view the output is to drag the .htm file to a browser but of course it can also be uploaded to a Service Request for evaluation by Oracle Support. Many of the Rule Sets will prompt you for information before they can execute their rules but the SOA Rule Set will identify the SOA domains configured in your RDA setup.cfg file. This means that you don't need to answer all of the questions again about where stuff is but it also means that you must have configured RDA for SOA. To run the Rule Set: Download the latest version of RDA from MOS Doc ID 314422.1 Configure RDA for your SOA domains. Detailed steps can be found here In it's simplest form the command is 'rda.cmd (.sh) -S SOA' Go to the RDA home location and enter the command 'rda.cmd (or .sh) -dT hcve' Select option '11' It should be noted that this our first release of a SOA Rule Set so there will probably be some things we need to clean up or fix. None of these rules will actually modify anything on your system as they are read only and do the evaluations internally. Please let us know if you have any issues with the rules or ideas for new ones so we can make them as useful as possible. The Checks Here is a list of the SOA health checks by ID, Name and Description. ID Name Description A00100 SOA Domain Homes Lists the SOA domains that were indentified from the RDA setup.cfg file A00200 Coherence Protocol Conflict Checks to see if you have both Unicast and Multicast configured in the same domain. Checks both the setDomainEnv and config.xml entries (if it exists). We recommend Unicast with fully qualified host names or IP addresses. A00210 Coherence Fully Qualified Host Checks that the host names are fully qualified or that IP addresses are used. Will fail if unqualified host names are detected. A00220 Unicast Local Host Checks that the Coherence localhost is specified for use with Unicast A00300 JTA Timeout Checks that the JTA timeout is configured for the domain and lists the value. The bundled rule will only list the current values of the JTA timeout for each SOA Domain. In the future the rule with fail with a warning if the value is 300 seconds or lower. It is recommended that timeouts follow the pattern 'syncMaxWaitTime' < EJB Timeouts < JTA Timeout. The 300 second value is important because the EJB Timeouts default to 300 seconds. Additional information can be found in MOS Doc ID 880313.1. A00310 XA Max Time Checks that the JTA Maximum XA call time is set for the domain. Fails if it is not explicitly set or if the value is less than or equal to the default of 12000 ms. A00320 XA Timeout Checks that the XA timeout is enabled and that the value is '0' for the SOA Data Source (SOADataSource-jdbc.xml) A00330 JDBC Statement Timeout Checks that the Statement Timeout is set for all SOA Data Sources. Fails if the value is not set or if it is set to the default of -1. A00400 XA Driver Checks that the SOA Data Source is configured to use an XA driver. Fails if it is not. A00410 JDBC Capacity Settings Checks that the minimum and maximum capacity are equal for all SOA Data Sources. Fails if they are not and lists specifically which data sources failed. A00500 SOA Roles Checks that the default SOA roles 'SOAAdmin' and 'SOAOperator' are configured for the soa-infra application in the file sytem-jazn-data.xml. Fails if they are not. A00700 SOA-INFRA Deployment Checks that the soa-infra application is deployed to either a cluster, all members of a cluster or a stand alone server. A00710 SOA Deployments Checks that the SOA related applications are deployed to the same domain members as soa-infra. A00720 SOA Library Deployments Checks that the SOA related libraries are deployed to the same domain members as soa-infra. A00730 Data Source Deployments Checks that the SOA Data Sources are all targeted to the same domain members as soa-infra

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  • Short Season, Long Models - Dealing with Seasonality

    - by Michel Adar
    Accounting for seasonality presents a challenge for the accurate prediction of events. Examples of seasonality include: ·         Boxed cosmetics sets are more popular during Christmas. They sell at other times of the year, but they rise higher than other products during the holiday season. ·         Interest in a promotion rises around the time advertising on TV airs ·         Interest in the Sports section of a newspaper rises when there is a big football match There are several ways of dealing with seasonality in predictions. Time Windows If the length of the model time windows is short enough relative to the seasonality effect, then the models will see only seasonal data, and therefore will be accurate in their predictions. For example, a model with a weekly time window may be quick enough to adapt during the holiday season. In order for time windows to be useful in dealing with seasonality it is necessary that: The time window is significantly shorter than the season changes There is enough volume of data in the short time windows to produce an accurate model An additional issue to consider is that sometimes the season may have an abrupt end, for example the day after Christmas. Input Data If available, it is possible to include the seasonality effect in the input data for the model. For example the customer record may include a list of all the promotions advertised in the area of residence. A model with these inputs will have to learn the effect of the input. It is possible to learn it specific to the promotion – and by the way learn about inter-promotion cross feeding – by leaving the list of ads as it is; or it is possible to learn the general effect by having a flag that indicates if the promotion is being advertised. For inputs to properly represent the effect in the model it is necessary that: The model sees enough events with the input present. For example, by virtue of the model lifetime (or time window) being long enough to see several “seasons” or by having enough volume for the model to learn seasonality quickly. Proportional Frequency If we create a model that ignores seasonality it is possible to use that model to predict how the specific person likelihood differs from average. If we have a divergence from average then we can transfer that divergence proportionally to the observed frequency at the time of the prediction. Definitions: Ft = trailing average frequency of the event at time “t”. The average is done over a suitable period of to achieve a statistical significant estimate. F = average frequency as seen by the model. L = likelihood predicted by the model for a specific person Lt = predicted likelihood proportionally scaled for time “t”. If the model is good at predicting deviation from average, and this holds over the interesting range of seasons, then we can estimate Lt as: Lt = L * (Ft / F) Considering that: L = (L – F) + F Substituting we get: Lt = [(L – F) + F] * (Ft / F) Which simplifies to: (i)                  Lt = (L – F) * (Ft / F)  +  Ft This latest expression can be understood as “The adjusted likelihood at time t is the average likelihood at time t plus the effect from the model, which is calculated as the difference from average time the proportion of frequencies”. The formula above assumes a linear translation of the proportion. It is possible to generalize the formula using a factor which we will call “a” as follows: (ii)                Lt = (L – F) * (Ft / F) * a  +  Ft It is also possible to use a formula that does not scale the difference, like: (iii)               Lt = (L – F) * a  +  Ft While these formulas seem reasonable, they should be taken as hypothesis to be proven with empirical data. A theoretical analysis provides the following insights: The Cumulative Gains Chart (lift) should stay the same, as at any given time the order of the likelihood for different customers is preserved If F is equal to Ft then the formula reverts to “L” If (Ft = 0) then Lt in (i) and (ii) is 0 It is possible for Lt to be above 1. If it is desired to avoid going over 1, for relatively high base frequencies it is possible to use a relative interpretation of the multiplicative factor. For example, if we say that Y is twice as likely as X, then we can interpret this sentence as: If X is 3%, then Y is 6% If X is 11%, then Y is 22% If X is 70%, then Y is 85% - in this case we interpret “twice as likely” as “half as likely to not happen” Applying this reasoning to (i) for example we would get: If (L < F) or (Ft < (1 / ((L/F) + 1)) Then  Lt = L * (Ft / F) Else Lt = 1 – (F / L) + (Ft * F / L)  

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  • Why should we use low level languages if a high level one like python can do almost everything? [closed]

    - by killown
    I know python is not suitable for things like microcontrolers, make drivers etc, but besides that, you can do everything using python, companys get stuck with speed optimizations for real hard time system but does forget other factors which one you can just upgrade your hardware for speed proposes in order to get your python program fit in it, if you think how much cust can the company have to maintain a system written in C, the comparison is like that: for example: 10 programmers to mantain a system written in c and just one programmer to mantain a system written in python, with python you can buy some better hardware to fit your python program, I think that low level languages tend to get more cost, since programmers aren't so cheaply than a hardware upgrade, then, this is my point, why should a system be written in c instead of python?

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  • Will Xubuntu 12.10 also have amazon ads?

    - by Miguel Guasch
    and thanks in advance for your comments: I'm currently using Ubuntu 12.04, and quite happy with it. I'm using the Unity desktop, and I've got no major complaints. My problem/question is: I've been reading on the news, forums, and different websites that the new version in 12.10, which i'll eventually have to upgrade to if I plan on using Ubuntu, has a lens/amazon function on the dash that sends queries to amazon. Now, this disturbs me a bit, since I don't want to see "shopping recommendations" everytime I look for something, be they from amazon or from "future partners". Does this new "function" only apply to the Unity desktop? If I switch to the Xfce desktop, will I be able to "save myself" from sending search data to amazon and/or shopping recommendations from them? Or will I have to entirely switch distributions, in order to evade this? Again, many thanks in advance for your comments and/or help. Regards, Miguel.

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  • How do I programatically determine which port a SQL Server is running on?

    - by Ralph Willgoss
    How do I programatically determine which port a SQL Server is running on?/*===== Param ref for xp_readerrorlog ===1. Value of error log file you want to read: 0 = current, 1 = Archive #1, 2 = Archive #2, etc...2. Log file type: 1 or NULL = error log, 2 = SQL Agent log3. Search string 1: String one you want to search for4. Search string 2: String two you want to search for to further refine the results5. Search from start time6. Search to end time7. Sort order for results: N'asc' = ascending, N'desc' = descendingHow many error logs do I have?SMSStudio -> Management -> SQL Server Logs -> (right click) -> configure = see values*/USE MasterGO--  get log countDECLARE @logcount intDROP TABLE #ResultCREATE TABLE #Result (ArchiveNo int, Date datetime, Size int)INSERT INTO #ResultEXEC xp_enumerrorlogsSET @logcount = (SELECT COUNT(*) FROM #Result)-- search logsDECLARE @counter intSET @counter = 0WHILE @counter <= @logcountBEGIN    EXEC xp_readerrorlog @counter, 1, N'Server is listening on', 'any', NULL, NULL, N'asc'    SET @counter = @counter + 1ENDGO

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  • Compiz command plugin won't register keyboard shortcuts

    - by David Moles
    Per this discussion I've enabled the Compiz commands plugin in order to try to bind some keyboard shortcuts to wmctrl actions. CCSM captures my keystrokes just fine, but no matter what keystroke I try or what command I bind it to (everything from my original intention of binding Super-1, Super-2 etc. to wmctrl -o 0,0, wmctrl -o 2560,0, etc., to binding Ctrl-Alt-Shift-L to gnome-terminal). Basic compiz shortcuts for window switching and so on -- even custom ones -- seem to work fine, but the command plugin doesn't seem to be working at all. I also notice the following symptom: when I open the keyboard shortcut tab in CCSM, the keyboard shortcuts often at first appear blank, though if you click on the blank button, the correct value is still there. Also possibly related, I've noticed that gnome-terminal doesn't seem to notice the Super key, though other apps (e.g. CCSM, Emacs) register it fine. Anyway, it seems like something's eating my keystrokes. Any ideas?

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  • Etymology of software project names [closed]

    - by Benoit
    I would like to have a reference community wiki here in order to know what etymology software name have or why they are named that way. I was wondering why Imagemagick's mogrify was named this way. Today I wondered the same for Apache Lucene. It would be handy to have a list here. Could we extend such a list? Let me start and let you edit it please. I will ask for this to be community wiki. For each entry please link to an external reference. GNU Emacs: stand for “Editor MACroS”. Apache Lucene: Armenian name Imagemagick mogrify: from “transmogrify”. Thanks.

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  • Script at Startup

    - by OttoRobba
    I'm using 10.10 and I need to run a script in order to get a windows-like international keyboard layout - basically, it changes how dead keys work. (Original script from this page http://t.tam.atbh.us/en/win-us-intl-4-linux/ ) Since I can't seem to manage to get it going from boot, I have to run a custom script to launch any application. The script: export GTK_IM_MODULE=xim setxkbmap us intl xmodmap -e 'keycode 48 = dead_acute dead_diaeresis dead_acute dead_diaeresis acute diaeresis' application_name So if I put abiword in the application_name, it runs abiword respecting the keyboard script. Ideally, the original script would start at boot and then any applications I use would function with it - just like what happens if I run it first in Terminal (without the app_name line) and then run apps from it. I tried to make the script run from boot by adding it to /etc/rc.local but to no avail. Tried to add it to init.d but that also didn't work. If anyone can help, I'd be most grateful.

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  • Simulating simultaneous entities

    - by Steven Jeuris
    Consider the need to simulate a set of entitities in an accurate way. All entities exist in an artificial timeline. Within 'steps' of this timeline, all entities can do certain operations. It is imperative that timed events, are handled accurately, and not in processing order. So simple threading isn't a proper simulation, nor is procedurally walking across all entities. Processing may be slow, accuracy is key here. I have some ideas how to implement this myself, but most likely something like this has been done before. Are there any frameworks available for these purposes? Is there any particular paradigm more suitable?

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  • Creating the Business Card Request InfoPath Form

    - by JKenderdine
    Business Card Request Demo Files Back in January I spoke at SharePoint Saturday Virginia Beach about InfoPath forms and Web Part deployment.  Below is some of the information and details regarding the form I created for the session.  There are many blogs and Microsoft articles on how to create a basic form so I won’t repeat that information here.   This blog will just explain a few of the options I chose when creating the solutions for SPS Virginia Beach.  The above link contains the zipped package files of the two InfoPath forms(no code solution and coded solution), the list template for the Location list I used, and the PowerPoint deck.  If you plan to use these templates, you will need to update the forms to work within your own environments (change data connections, code links, etc.).  Also, you must have the SharePoint Enterprise version, with InfoPath Services configured in order to use the Web Browser enabled forms. So what are the requirements for this template? Business Card Request Form Template Design Plan: Gather user information and requirements for card Pull in as much user information as possible. Use data from the user profile web services as a data source Show and hide fields as necessary for requirements Create multiple views – one for those submitting the form and Another view for the executive assistants placing the orders. Browser based form integrated into SharePoint team site Submitted directly to form library The base form was created using the blank template.  The table and rows were added using Insert tab and selecting Custom Table.  The use of tables is a great way to make sure everything lines up.  You do have to split the tables from time to time.  If you’ve ever split cells and then tried to re-align one to find that you impacted the others, you know why.  Here is what the base form looks like in InfoPath.   Show and hide fields as necessary for requirements You will notice I also used Sections within the form.  These show or hide depending on options selected or whether or not fields are blank.  This is a great way to prevent your users from feeling overwhelmed with a large form (this one wouldn’t apply).  Although not used in this one, you can also use various views with a tab interface.  I’ll show that in another post. Gather user information and requirements for card Pull in as much user information as possible. Use data from the user profile web services as a data source Utilizing rules you can load data when the form initiates (Data tab, Form Load).  Anything you can automate is always appreciated by the user as that is data they don’t have to enter.  For example, loading their user id or other user information on load: Always keep in mind though how much data you load and the method for loading that data (through rules, code, etc.).  They have an impact on form performance.  The form will take longer to load if you bring in a ton of data from external sources.  Laura Rogers has a great blog post on using the User Information List to load user information.   If the user has logged into SharePoint, then this can be used quite effectively and without a huge performance hit.   What I have found is that using the User Profile service via code behind or the Web Service “GetUserProfileByName” (as above) can take more time to load the user data.  Just food for thought. You must add the data connection in order for the above rules to work.  You can connect to the data connection through the Data tab, Data Connections or select Manage Data Connections link which appears under the main data source.  The data connections can be SharePoint lists or libraries, SQL data tables, XML files, etc.  Create multiple views – one for those submitting the form and Another view for the executive assistants placing the orders. You can also create multiple views for the users to enhance their experience.  Once they’ve entered the information and submitted their request for business cards, they don’t really need to see the main data input screen any more.  They just need to view what they entered. From the Page Design tab, select New View and give the view a name.  To review the existing views, click the down arrow under View: The ReviewView shows just what the user needs and nothing more: Once you have everything configured, the form should be tested within a Test SharePoint environment before final deployment to production.  This validates you don’t have any rules or code that could impact the server negatively. Submitted directly to form library   You will need to know the form library that you will be submitting to when publishing the template.  Configure the Submit data connection to connect to this library.  There is already one configured in the sample,  but it will need to be updated to your environment prior to publishing. The Design template is different from the Published template.  While both have the .XSN extension, the published template contains all the “package” information for the form.  The published form is what is loaded into Central Admin, not the design template. Browser based form integrated into SharePoint team site In Central Admin, under General Settings, select Manage Form Templates.  Upload the published form template and Activate it to a site collection. Now it is available as a content type to select in the form library.  Some documentation on publishing form templates:  Technet – Manage administrator approved form templates And that’s all our base requirements.  Hope this helps to give a good start.

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  • Starting web development with ASP.Net [closed]

    - by nayef harb
    Possible Duplicate: Fastest way to get up to speed on webapp development with ASP.NET? If you develop with ASP.NET, which other technologies do you use? How much do i need to learn in order to get an entry level asp.net job? training plan for asp.net and c# Trying to learn ASP.NET What should every programmer know about web development? I learned web development in ASP.Net couple of month ago in college, nothing serious just couple of general lessons. But now I am confused where to start, should I start with HTML and JavaScript before ASP.Net?

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  • SEO Implications of blog on site versus offsite?

    - by Kelli Davis
    I recently added a blog to one of our company's websites, and was confident that this increase in content on the site would have only positive SEO results. My boss, however, feels that we should have instead located the blog off-site, on a blogging platform such as Wordpress, Typepad, etc., in order to generate a backlink (assuming we'd link from blogging platform back to website.) While I know that backlinks are important for SEO, isn't content creation equally, if not more, important? Granted, I'd be creating content either way, but I figured we'd get more site traffic by having the blog located on our site versus a separate blogging platform. Am I incorrect in my priorities here? Boss's TOP priority is increasing the ranking of our website, so maybe a backlink would be better...? If we do need to relocate the blog to an off-site platform, is there a blogging platform that is more conducive to SEO than others? Is there a platform from which backlinks would be more valuable than others?

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  • 2D pathfinding - finding smooth paths

    - by Kooi Nam Ng
    I was trying to implement a simple pathfinding, but the outcome is less satisfactory than what I intended to achieve. The thing is units in games like Starcraft 2 move in all directions whereas units in my case only move in at most 8 directions (Warcraft 1 style) as these 8 directions direct to next available nodes (they move from a tile to next neighboring tile). What should I do in order to achieve the result as in Starcraft 2? Shrink the tile size? On the picture you can see a horizontal line of rock tiles being obstacles, and the found path marked as green tiles. The red line is the path I want to achieve.

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  • The Joy Of Hex

    - by Jim Giercyk
    While working on a mainframe integration project, it occurred to me that some basic computer concepts are slipping into obscurity. For example, just about anyone can tell you that a 64-bit processor is faster than a 32-bit processer. A grade school child could tell you that a computer “speaks” in ‘1’s and ‘0’s. Some people can even tell you that there are 8 bits in a byte. However, I have found that even the most seasoned developers often can’t explain the theory behind those statements. That is not a knock on programmers; in the age of IntelliSense, what reason do we have to work with data at the bit level? Many computer theory classes treat bit-level programming as a thing of the past, no longer necessary now that storage space is plentiful. The trouble with that mindset is that the world is full of legacy systems that run programs written in the 1970’s.  Today our jobs require us to extract data from those systems, regardless of the format, and that often involves low-level programming. Because it seems knowledge of the low-level concepts is waning in recent times, I thought a review would be in order.       CHARACTER: See Spot Run HEX: 53 65 65 20 53 70 6F 74 20 52 75 6E DECIMAL: 83 101 101 32 83 112 111 116 32 82 117 110 BINARY: 01010011 01100101 01100101 00100000 01010011 01110000 01101111 01110100 00100000 01010010 01110101 01101110 In this example, I have broken down the words “See Spot Run” to a level computers can understand – machine language.     CHARACTER:  The character level is what is rendered by the computer.  A “Character Set” or “Code Page” contains 256 characters, both printable and unprintable.  Each character represents 1 BYTE of data.  For example, the character string “See Spot Run” is 12 Bytes long, exclusive of the quotation marks.  Remember, a SPACE is an unprintable character, but it still requires a byte.  In the example I have used the default Windows character set, ASCII, which you can see here:  http://www.asciitable.com/ HEX:  Hex is short for hexadecimal, or Base 16.  Humans are comfortable thinking in base ten, perhaps because they have 10 fingers and 10 toes; fingers and toes are called digits, so it’s not much of a stretch.  Computers think in Base 16, with numeric values ranging from zero to fifteen, or 0 – F.  Each decimal place has a possible 16 values as opposed to a possible 10 values in base 10.  Therefore, the number 10 in Hex is equal to the number 16 in Decimal.  DECIMAL:  The Decimal conversion is strictly for us humans to use for calculations and conversions.  It is much easier for us humans to calculate that [30 – 10 = 20] in decimal than it is for us to calculate [1E – A = 14] in Hex.  In the old days, an error in a program could be found by determining the displacement from the entry point of a module.  Since those values were dumped from the computers head, they were in hex. A programmer needed to convert them to decimal, do the equation and convert back to hex.  This gets into relative and absolute addressing, a topic for another day.  BINARY:  Binary, or machine code, is where any value can be expressed in 1s and 0s.  It is really Base 2, because each decimal place can have a possibility of only 2 characters, a 1 or a 0.  In Binary, the number 10 is equal to the number 2 in decimal. Why only 1s and 0s?  Very simply, computers are made up of lots and lots of transistors which at any given moment can be ON ( 1 ) or OFF ( 0 ).  Each transistor is a bit, and the order that the transistors fire (or not fire) is what distinguishes one value from  another in the computers head (or CPU).  Consider 32 bit vs 64 bit processing…..a 64 bit processor has the capability to read 64 transistors at a time.  A 32 bit processor can only read half as many at a time, so in theory the 64 bit processor should be much faster.  There are many more factors involved in CPU performance, but that is the fundamental difference.    DECIMAL HEX BINARY 0 0 0000 1 1 0001 2 2 0010 3 3 0011 4 4 0100 5 5 0101 6 6 0110 7 7 0111 8 8 1000 9 9 1001 10 A 1010 11 B 1011 12 C 1100 13 D 1101 14 E 1110 15 F 1111   Remember that each character is a BYTE, there are 2 HEX characters in a byte (called nibbles) and 8 BITS in a byte.  I hope you enjoyed reading about the theory of data processing.  This is just a high-level explanation, and there is much more to be learned.  It is safe to say that, no matter how advanced our programming languages and visual studios become, they are nothing more than a way to interpret bits and bytes.  There is nothing like the joy of hex to get the mind racing.

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  • How to design network protocols

    - by dandroid
    As a programmer, you work on your software design skills. You learn about things such as modularity and reusability and how you can achieve them in code. There's plenty of literature on the subject and engineers talk about it all the time. What about if you want to design network protocols? How do you judge that protocol X is badly designed while Y is well designed? (eg. in programming you are often pointed out to a well-written piece of code in order to learn from it - what is the equivalent for network protocols?) For example, suppose I want to design a P2P protocol similar to BitTorrent or I want to make a better version of the Socks protocol. How would I go about doing a good job on this? Thanks!

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  • BTrFS subvolume / snapshot question

    - by bumbling fool
    I think I'm having difficulty fully understanding subvolumes and snapshots. The /home partition is btrfs. I want to create a "backup" snapshot of /home/user (for example) but user has existed for years (previously ext4 btrfs-convert). I believe you can only make a snapshot of a subvolume. I checked and there are no "default" subvolumes already present. 1) Is there another way for me to backup /home/user other than creating a subvolume /home/user2 and copying everything from user to user2 in order to snapshot it?

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  • Planning an Event&ndash;SPS NYC

    - by MOSSLover
    I bet some of you were wondering why I am not going to any events for the most part in June and July (aside from volunteering at SPS Chicago).  Well I basically have no life for the next 2 months.  We are approaching the 11th hour of SharePoint Saturday New York City.  The event is slated to have 350 to 400 attendees.  This is second year in a row I’ve helped run it with Jason Gallicchio.  It’s amazingly crazy how much effort this event requires versus Kansas City.  It’s literally 2x the volume of attendees, speakers, and sponsors plus don’t even get me started about volunteers.  So here is a bit of the break down… We have 30 volunteers+ that Tasha Scott from the Hampton Roads Area will be managing the day of the event to do things like timing the speakers, handing out food, making sure people don’t walk into the event that did not sign up until we get a count for fire code, registering people, watching the sharpees, watching the prizes, making sure attendees get to the right place,  opening and closing the partition in the big room, moving chairs, moving furniture, etc…Then there is Jason, Greg, and I who will be making sure that the speakers, sponsors, and everything is going smoothly in the background.  We need to make sure that everything is setup properly and in the right spot.  We also need to make sure signs are printed, schedules are created, bags are stuffed with sponsor material.  Plus we need to send out emails to sponsors reminding them to send us the right information to post on the site for charity sessions, send us boxes with material to stuff bags, and we need to make sure that Michael Lotter gets there information for invoicing.  We also need to check that Michael has invoiced everyone and who has paid, because we can’t order anything for the event without money.  Once people have paid we need to setup food orders, speaker and volunteer dinners, buy prizes, buy bags, buy speakers/volunteer/organizer shirts, etc…During this process we need all the abstracts from speakers, all the bios, pictures, shirt sizes, and other items so we can create schedules and order items.  We also need to keep track of who is attending the dinner the night before for volunteers and speakers and make sure we don’t hit capacity.  Then there is attendee tracking and making sure that we don’t hit too many attendees.  We need to make sure that attendees know where to go and what to do.  We have to make all kinds of random supply lists during this process and keep on track with a variety of lists and emails plus conference calls.  All in all it’s a lot of work and I am trying to keep track of it all the top so that we don’t duplicate anything or miss anything.  So basically all in all if you don’t see me around for another month don’t worry I do exist. Right now if you look at what I’m doing I am traveling every Monday morning and Thursday night back and forth to Washington DC from New Jersey.  Every night I am working on organizational stuff for SharePoint Saturday New York City.  Every Tuesday night we are running an event conference call.  Every weekend I am either with family or my boyfriend and cat trying hard not to touch the event.  So all my time is pretty much work, event, and family/boyfriend.  I have 0 bandwidth for anything in the community.  If you compound that with my severe allergy problems in DC and a doctor’s appointment every month plus a new med once a week I’m lucky I am still standing and walking.  So basically once July 30th hits hopefully Jason Gallicchio, Greg Hurlman, and myself will be able to breathe a little easier.  If I forget to do this thank you Greg and Jason.  Thank you Tom Daly.  Thank you Michael Lotter.  Thank you Tasha Scott.  Thank you Kevin Griffin.  Thank you all the volunteers, speakers, sponsors, and attendees who will and have made this event a success.  Hopefully, we have enough time until next year to regroup, recharge, and make the event grow bigger in a different venue.  Awesome job everyone we sole out within 3 days of registration and we still have several weeks to go.  Right now the waitlist is at 49 people with room to grow.  If you attend the event thank all these guys I mentioned above for making it possible.  It’s going to be awesome I know it but I probably won’t remember half of it due to the blur of things that we will all be taking care of the day of the event.  Catch you all in the end of July/Early August where I will attempt to post something useful and clever and possibly while wearing a fez. Technorati Tags: SPS NYC,SharePoint Saturday,SharePoint Saturday New York City

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  • Virtual Host under MacOSX not working

    - by David Casillas
    I have setup a virtualhost for MacOSX Apache instalation. This are my steps: edit /private/etc/apache2/httpd.conf removing comment from: Include /private/etc/apache2/extra/httpd-vhosts.conf edit /private/etc/apache2/extra/httpd-vhosts.conf, added: <VirtualHost *:80> ServerName test.local DocumentRoot "/Users/myusername/Sites/Test/public" <Directory "/Users/myusername/Sites/Test/public"> Options Indexes FollowSymLinks Includes AllowOverride All Order allow,deny Allow from all </Directory> </VirtualHost> edit /private/etc/hosts added 127.0.0.7 test.local Restart Apache But the VirtualHost does not work. To further isolate the problem I check the same configuration with MAMP and the virtual host worked rigth, so the configuration files should be fine. What can be wrong?

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