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• Solution for developers wanting to run a standalone WLS 10.3.6 server against JDev 11.1.1.6.0

  - by Chris Muir

  In my previous post I discussed how to install the 11.1.1.6.0 ADF Runtimes into a standalone WLS 10.3.6 server by using the ADF Runtime installer, not the JDeveloper installer.  Yet there's still a problem for developers here because JDeveloper 11.1.1.6.0 comes coupled with a WLS 10.3.5 server.  What if you want to develop, deploy and test with a 10.3.6 server?  Have we lost the ability to integrate the IDE and the WLS server where we can run and stop the server, deploy our apps automatically the server and more? JDeveloper actually solved this issue sometime back but not many people will have recognized the feature for what it does as it wasn't needed until now. Via the Application Server Navigator you can create 2 types of connections, one to a remote "standalone WLS" and another to an "integrated WLS".  It's this second option that is useful because what we can do is install a local standalone WLS 10.3.6 server on our developer PC, then create a separate "integrated WLS" connection to the standalone server.  Then by accessing your Application's properties through the Application menu -> Application Properties -> Run -> Bind to Integration Application Server option we can choose the newly created WLS server connection to work with our application. In this way JDeveloper will now treat the new server as if it was the integrated WLS.  It will start when we run and deploy our applications, terminate it at request and so on.  Of course don't forget you still need to install the ADF Runtimes for the server to be able to work with ADF applications. Note there is bug 13917844 lurking in the Application Server Navigator for at least JDev 11.1.1.6.0 and earlier.  If you right click the new connection and select "Start Server Instance" it will often start one of the other existing connections instead (typically the original IntegratedWebLogicServer connection).  If you want to manually start the server you can bypass this by using the Run menu -> Start Server Instance option which works correctly.

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• Are there any drawbacks to the Major.Minor.YMDD.Build version strategy?

  - by Chu

  I'm trying to come up with a good version strategy to fit our specific needs. We've proposed settling on this and I wanted to ask the question to see if anyone's experience would suggest avoiding this or altering it in any way. Here's our proposal: Versions are released in this format: MAJOR.MINOR.YMDD.BN. Here it is broken out: MAJOR & MINOR are typical; we'll increase MINOR when we feel code and new feature sets warrants it; once every few months most likely. MAJOR will increase ~yearly. YMDD: Y will be the last digit of the current year, so "1" for 2011, "2" for 2012, etc. A non-padded month will be used to keep the number smaller (9 instead of 09 for example). DD of course is the day, padded with a zero for days under 10. BN: BN is the build number and increases by one anytime we make a change to a branch of the code represented by the build, for example: If were to make a build today, our release would be version 5.0.1707.1. I release to QA today and 3 days from now QA finds that a change broke the save functionality on a page. Instead of me changing our current development code, I'd go back to the code that I used to create version 5.0.1707.1, make the fix there, then increase the BN portion of the version and would then re-release 5.0.1707.2 back to QA. In short, anytime a change is made to a branched version that isn't the active dev branch, we'd use the original version number and increase only the BN portion (even if the change happened 3 days, 3 weeks or 3 months from the initial release of that version). Anytime we make a new release from our Active dev branch, we'd come up with a new version based on the M/D of the release using the outlined strategy. We do this once every 2-3 weeks. Are there holes or pitfalls with this? If so, what are they? Thanks EDIT To clarify one point that I didn't get out very well - Oct/Nov/Dec will be two digits, it's only the year that won't be. So 9 for Sept, 10 for Oct, 11 for Nov, etc.

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• I can't install Ubuntu 12.04.1 on iMac G5

  - by user89004

  So, I have this iMac G5 that doesn't have iSight, only a small light sensor I think undernieth, machine model 8.2. I tried burning a Ubuntu 12.04.1 PowerPC 64bit .iso to a cd but the computer just won't boot it, I don't know why. Next I tried with a USB but it wouldn't let me boot that either, I created the usb on my dad's win7 laptop as the process was way easier than on freakin Mac or Ubuntu (no command typing AT ALL on windows) I'm able to get into openfirmware and type boot usb and it does show some weird writing that scrolls so fast I can't see anything and then it just gives me this huge no sign like a stop sign and freezez. The sign is grey and the line in the middle is tilted towards the left. An other issue I'm having with hdiutil is that I can't convert the stupid .iso I just downloaded into a .img because the file keeps on dissapearing right when it's done converting it. I used the syntax from Ubuntu support how to create a bootable usb drive under Mac OS X. I even didn't include the 2 stupid ~ that are shown in the syntax that are completly worthless, God only know why they put them there, and I even tried running the whole thing as root with sudo su before the command. The funny thing is that if I convert something smaller it works. The command I was using is hdiutil convert -format UDRW -o /path/to/target.img /path/to/ubuntu.iso I even tried hdiutil convert /path/to/ubuntu.iso -format UDRW -o /path/to/target.img but the same thing happens, the dummy .img.dmg file dissapears when the conversion is done no matter where I set the output file to go. I have tried several different folders, the same thing happens with all of them. I also tried burning a Ubuntu mini iso on a cd, can't remember if it was 11.10 or 12.10 but even thoguh holding c when the iMac boots up does show me the cd and I can boot from it, I get this weird error upon hitting install, it says something like invalid memory access, release keys and error strings I can't read. I don't have any original DVDs from this iMac and can't run hardware diagnostics. WHatever option I try at the command prompt from the mini ubuntu cd I get the same result, error code and openfirmware backdrop that's frozen. I noticed that the pen drive I created on my dads Win7 laptop is formated with MS-DOS but I can still mount it no problem, so it shouldn't have a problem booting it, right? I used the advice on ubuntu.com to make it, from here. Also, my partition is HFS+ so I can't use it as a hard drive and boot from it. I don' have 2 partitions either, just one HDD, one partition. Please help!!!

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• 2D Grid Map Connectivity Check (avoiding stack overflow)

  - by SombreErmine

  I am trying to create a routine in C++ that will run before a more expensive A* algorithm that checks to see if two nodes on a 2D grid map are connected or not. What I need to know is a good way to accomplish this sequentially rather than recursively to avoid overflowing the stack. What I've Done Already I've implemented this with ease using a recursive algorithm; however, depending upon different situations it will generate a stack overflow. Upon researching this, I've come to the conclusion that it is overflowing the stack because of too many recursive function calls. I am sure that my recursion does not enter an infinite loop. I generate connected sets at the beginning of the level, and then I use those connected sets to determine connectivity on the fly later. Basically, the generating algorithm starts from left-to-right top-to-bottom. It skips wall nodes and marks them as visited. Whenever it reaches a walkable node, it recursively checks in all four cardinal directions for connected walkable nodes. Every node that gets checked is marked as visited so they aren't handled twice. After checking a node, it is added to either a walls set, a doors set, or one of multiple walkable nodes sets. Once it fills that area, it continues the original ltr ttb loop skipping already-visited nodes. I've also looked into flood-fill algorithms, but I can't make sense of the sequential algorithms and how to adapt them. Can anyone suggest a better way to accomplish this without causing a stack overflow? The only way I can think of is to do the left-to-right top-to-bottom loop generating connected sets on a row basis. Then check the previous row to see if any of the connected sets are connected and then join the sets that are. I haven't decided on the best data structures to use for that though. I also just thought about having the connected sets pre-generated outside the game, but I wouldn't know where to start with creating a tool for that. Any help is appreciated. Thanks!

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• Restoring MSDB

  - by David-Betteridge

  We recently performed a disaster recovery exercise which included the restoration of the MSDB database onto our DR server.  I did a quick google to see if there were any special considerations and found the following MS article.  Considerations for Restoring the model and msdb Databases (http://msdn.microsoft.com/en-us/library/ms190749(v=sql.105).aspx).   It said both the original and replacement servers must be on the same version,  I double-checked and in my case they are both SQL Server 2008 R2 SP1 (10.50.2500).. So I went ahead and stopped SQL Server agent, restored the database and restarted the agent.  Checked the jobs and they were all there, everything looked great, and was until the server was rebooted a few days later.Then the syspolicy_purge_history job started failing on the 3rd step with the error message “Unable to start execution of step 3 (reason: The PowerShell subsystem failed to load [see the SQLAGENT.OUT file for details]; The job has been suspended). The step failed.”   A bit more googling pointed me to the msdb.dbo.syssubsystems table SELECT * FROM msdb.dbo.syssubsystems WHERE start_entry_point ='PowerShellStart'   And in particular the value for the subsystem_dll. It still had the path to the SQLPOWERSHELLSS.DLL but on the old server. The DR instance has a different name to the live instance and so the paths are different.   This was quickly fixed with the following SQL Use msdb; GO sp_configure 'allow updates', 1 ; RECONFIGURE WITH OVERRIDE ; GO UPDATE msdb.dbo.syssubsystems SET subsystem_dll='C:\Program Files\Microsoft SQL Server\MSSQL10_50.DR\MSSQL\binn\SQLPOWERSHELLSS.DLL' WHERE start_entry_point ='PowerShellStart'; GO sp_configure 'allow updates', 0; RECONFIGURE WITH OVERRIDE ; GO Stopped and started SQL Server agent and now the job completes.   I then wondered if anything else might be broken, SELECT subsystem_dll FROM msdb.dbo.syssubsystems Shows a further 10 wrong paths – fortunately for parts of SQL (replication, SSIS etc) we aren’t using! Lessons Learnt 1.       DR exercises are a good thing! 2.       Keep the Live and DR environments as similar as possible.    

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• Rails program is not being run on apache + passenger - only directory listing

  - by user909943

  I have successfully installed Phusion passenger + Apache 2 + Rails 3.1 program + git on a linux Debian 6. I ran passenger-install-apache2-module and followed the configuration instructions. I followed also the setup instructions at https://help.ubuntu.com/community/RubyOnRails#Configure%20Apache My program is in /var/www/myrailsproject and runs fine on webrick on my mac. When going to myhomepage.com (example) I only see directory listing. By preventing directory listing and setting Options -Indexes in < Document tag in /etc/apache2/sites-available default or myhomepage.com I get an error on my website: Forbidden You don't have permission to access / on this server. Apache/2.2.19 (Debian) Server at myhomepage.com Port 80 In /etc/apache2/apache.conf I added: ServerName myhomepage.com LoadModule passenger_module /usr/lib/ruby/gems/1.8/gems/passenger-3.0.8/ext/apache2/mod_passenger.so PassengerRoot /usr/lib/ruby/gems/1.8/gems/passenger-3.0.8 PassengerRuby /usr/bin/ruby1.8 In /etc/apache2/sites-available myhomepage.com: < VirtualHost *:80 ServerName myhomepage.com ServerAlias www.myhomepage.com DocumentRoot /var/www/myrailsproject/public ErrorLog /var/www/logs/error.log CustomLog /var/www/logs/access.log combined RailsEnv test RackEnv test RailsBaseURI /mayrailsproject < Directory /var/www/myrailsproject> Options -Indexes FollowSymLinks -MultiViews AllowOverride all Order allow,deny allow from all < /Directory> < Directory /var/www/myrailsproject/public> AllowOverride All Options -Indexes +FollowSymLinks MultiViews Order allow,deny Allow from all < /Directory> RailsSpawnMethod smart PassengerPoolIdleTime 1000 RailsAppSpawnerIdleTime 0 RailsFrameworkSpawnerIdleTime 0 PassengerMaxRequests 5000 PassengerStatThrottleRate 5 < /VirtualHost I think I have tried all possible combinations of values and variables in < Directory (and < Directory /, < Directory /var/www etc.) the dafault looks like: < VirtualHost *:80 ServerName myhomepage.com RailsBaseURI /myrailsproject DocumentRoot /var/www/myrailsproject/public RackEnv test RailsEnv test < Directory /var/www/myrailsproject> Options -Indexes FollowSymLinks -MultiViews AllowOverride None Order deny,allow Deny from all < /Directory> <Directory /root/public/myrailsproject/public> Options -Indexes FollowSymLinks -MultiViews AllowOverride All Order allow,deny allow from all </Directory> ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/ <Directory "/usr/lib/cgi-bin"> AllowOverride None Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all </Directory> ErrorLog ${APACHE_LOG_DIR}/error.log LogLevel warn CustomLog ${APACHE_LOG_DIR}/access.log combined Alias /doc/ "/usr/share/doc/" < Directory "/usr/share/doc/"> Options Indexes MultiViews FollowSymLinks AllowOverride None Order deny,allow Deny from all Allow from 127.0.0.0/255.0.0.0 ::1/128 < /Directory> < /VirtualHost So I wonder why my rails project is not being run, only directory listing. I do not have any index file in my project, routes.rb routes to root :to = 'static_pages#home' I think all permissions are as they should be. Thanks a lot in advance Regards Íris

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• Minimizing Dependencies For GUIs

  - by tuba09

  I've been working on a project, and have been charged with designing the projects GUI front-end. I'm coding in Java and using the Swing toolkit. Usability-wise, the GUI front-end follows all of Nielsen's heuristics. Users can easily get to where they want to go through the click of a button / JComboBox. Essentially, in Swing terms, what happens is their actions drive the creation/deletion of custom panels. The GUI is coming along fine for the most part. However, I have to admit to being utterly dismayed at the tight web of dependencies my code is being smothered in. The main problem that I've encountered, that I haven't been able to fix as of yet, is how to keep a reference to the panels/buttons being changed. I'll give an example: Say there's a button A Say there's a panel B displaying picture C Say there's another picture D (not currently being displayed by panel B) When user clicks A, panel B should remove picture C and display picture D My question is, what's the best way of keeping track of panel B? Since I need a global point of access to panel B, my solution has so far been to just shoehorn it into a static variable, and access it through a series of static getters and setters. And this static variable is usually stored in the reference's original class. I.e. UserPanel has a static variable that stores a reference to itself. Is there an easy, tried-and-true way of dealing with these kinds of situations? Like my GUI works fine, but it is not modular and/or robust at all. To add to this, the dreaded 'cyclical dependencies' issue that's shunned by so many programmers is out here in full effect. I'm fairly new to development and just want to make sure that my code will be fairly extensible and won't cause much of a headache to the next person that decides to get a try at it. I know there's loads of books out there that probably have a nice elegant solution to this, but unfortunately I just don't have the time to leisure read right now. I need something that's quick and dirty. Thanks in advance

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• Less Can Be More In E-Commerce

  - by Michael Hylton

  Today’s consumers are inundated with product choices and vendors. Visit your favorite electronics retailer and see the vast assortment of flat panel televisions. Or the variety of detergents at the supermarket. All of this can be daunting for the average consumer who is looking for the products and services that interest them.  In a study titled “Choice is Demotivating: Can One Desire Too Much of a Good Thing”, the author, Sheena Iyengar found that participants actually reported greater subsequent satisfaction with their selections and wrote better essays when their original set of options had been limited. The same can be said for e-commerce and your website. Being able to quickly convert shoppers into buyers with effective merchandising is what makes leading businesses successful. You want to engage each individual visitor with the most-relevant content to drive higher conversions and order values while decreasing abandonment, but predicting what will resonate with each customer is difficult. In a world of choices, online merchandizing tools can help personalize, streamline, and refine what your customers view when they browse your online catalog. The key to being effective is to align your products and content as closely as possible with the customer’s needs. The goal on the home page is to promote your brand and push visitors farther into the site. The home page is often the starting point for repeat customers as well as for new visitors hoping to address their current product needs. As the customer selects different filters and narrows the choices, valuable information is being provided to the retailer about the customer’s current need—regardless of previous search behavior or what other customers with a similar demographic profile have purchased. Together with search pages, category browse pages are among the primary options available to customers as a means of finding products on your site. Once a customer reaches the product detail page, it is clear what that person desires, regardless of the segment the customer falls into. However, don’t disregard campaign-based promotions completely. A campaign targeted to all customers but featuring rule-driven promotions tied to the product can be effective. Click here to learn more about merchandizing techniques so what your customer sees if half full and not half empty.

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• Less Can Be More In E-Commerce

  - by Michael Hylton

  Today’s consumers are inundated with product choices and vendors. Visit your favorite electronics retailer and see the vast assortment of flat panel televisions. Or the variety of detergents at the supermarket. All of this can be daunting for the average consumer who is looking for the products and services that interest them.  In a study titled “Choice is Demotivating: Can One Desire Too Much of a Good Thing”, the author, Sheena Iyengar found that participants actually reported greater subsequent satisfaction with their selections and wrote better essays when their original set of options had been limited. The same can be said for e-commerce and your website. Being able to quickly convert shoppers into buyers with effective merchandising is what makes leading businesses successful. You want to engage each individual visitor with the most-relevant content to drive higher conversions and order values while decreasing abandonment, but predicting what will resonate with each customer is difficult. In a world of choices, online merchandizing tools can help personalize, streamline, and refine what your customers view when they browse your online catalog. The key to being effective is to align your products and content as closely as possible with the customer’s needs. The goal on the home page is to promote your brand and push visitors farther into the site. The home page is often the starting point for repeat customers as well as for new visitors hoping to address their current product needs. As the customer selects different filters and narrows the choices, valuable information is being provided to the retailer about the customer’s current need—regardless of previous search behavior or what other customers with a similar demographic profile have purchased. Together with search pages, category browse pages are among the primary options available to customers as a means of finding products on your site. Once a customer reaches the product detail page, it is clear what that person desires, regardless of the segment the customer falls into. However, don’t disregard campaign-based promotions completely. A campaign targeted to all customers but featuring rule-driven promotions tied to the product can be effective. Click here to learn more about merchandizing techniques so what your customer sees if half full and not half empty.

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• Live CD has black screen HP DV6

  - by Shaun Killingbeck

  Attempting to install/try ubuntu (11.10, 12.04) on my new laptop, using a liveCD (and tried USB). I get the purple screen (with the man/keyboard at the bottom) and after that the screen flashes bright white before going black. Ubuntu continues to load in the background, with login sound etc but the screen is off. I have tried as many different solutions as I could find including: using nomodestep, xforcevesa, i915.modeset=0, and also now i915.modeset=1 in boot options (seperately): varying consequences, but either I end up at a blinking cursor with no prompt, a command line (startx fails: no screen found), or the original blank screen again Tried booting from VirtualBox - it crashes at the same place the screen would go blank when using a CD/USB tried 11.04: I don't have this problem BUT when trying to install, I get a ubi-partman error 141 (possibly down to the three partitions that came on my laptop... not sure why HP needed there own separate partition for HP Tools...) Model: HP Pavillion DV6 6B08SA Processor: AMD Quad-Core A6-3410MX APU with Radeon HD 6545G2 Dual Graphics (1.6 GHZ 4 MB L2 cache ) Chipset: AMD RS880M Any help would be greatly appreciated. I just want to be able to partition the drive and install Ubuntu. I'm assuming the issue is graphics card related, although I have no confirmation of that. Update: Tried the ?orkarounds on https://wiki.ubuntu.com/X/Troubleshooting/BlankScreen - set gfxpayload=text changed nothing, removing splash did nothing and setting vesafb.nonsense=1 did nothing either. I'd like to be able to collect some log information somehow, but I can't get to a command line from the liveCD. tried using the latest 12.04 beta, same issue tried nomodeset without splash or quiet. get the following (tail of) output before it freezes on that screen: * Starting configure network device security [OK] * Starting configure network device [OK] [ 25.720899] ieee80211 phy0: w1_ops_config: change monitor mode: false (implement) [ 25.720923] ieee80211 phy0: w1_ops_config: change power-save mode: false (implement) * Starting restore sound card(s') mixer state(s) [fail] [ 25.721849] ieee80211 phy0: w1_ops_bss_info_changed: qos enabled: false (implement) * Stopping save kernel messages [OK] * Starting bluetooth [OK] * PulseAudio configured for per-user sessions saned disabled; edit /etc/default/saned [ 25.988016] hci_cmd_timer: hci0 command tx timeout [ 26.207225] bad LUN (0:1) [ 26.223735] bad target number (1:0) [ 26.252111] bad target number (2:0) [ 26.272170] bad target number (3:0) [ 26.300154] bad target number (4:0) [ 26.328162] bad target number (5:0) [ 26.344180] bad target number (6:0) [ 26.368142] bad target number (7:0) * Checking battery state... [OK] * Stopping System V runlevel capability [OK] Does this give any indication of the problem? the false (implement) messages also reappear when I press the power button to ask it to shutdown, followed by a [fail] status for killing remaining processes.

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• Ubuntu won't connect to wired network

  - by djeikyb

  I'm running 10.04, upgraded from 9.10, maybe, but probably not upgraded from 9.04. I have two wifi routers. Zeus is connected to the dsl modem. Hermes uses a wds bridge with Zeus to extend the network. My desktop (Daedalus) is ethernetted to Hermes. My laptop (Clyde) is wifi, switching to Hermes or Zeus as needed. Occasionally, as in whenever I transfer a large file from desktop to laptop, the wds bridge will die. Fixing it means restarting both routers, though it seems Hermes should boot first. This is ridiculous, and eventually I'll get around to asking you guys to help me stop it from happening. More importantly is that my desktop requires a reboot to get back on the network. WTF. ifconfig shows my nic has no ip. /etc/init.d/networking restart doesn't do anything, not even give me a lousy ip. dhcpcd eth1 grants me an ip address, but doesn't help with internet access. route -n shows what looks like my normal routing table, but pinging google.com informs me it's an unknown host. jake@daedalus:~$ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.1.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1 0.0.0.0 10.1.1.1 0.0.0.0 UG 0 0 0 eth1 It may be worth noting that I can ping both Zeus (10.1.1.1) and Hermes (10.1.1.4) and my laptop (10.1.1.55). Much obliged for any help. Rebooting is, well, trivial in this instance. But it's stupid. I switched to linux because I like the idea that if one part breaks, you fix it instead of reboot reboot reboot. I've left my poor desktop in disarray, confining myself to my little netbook. My desktop is broken, awaiting magical commands from you brilliant folk. (and yes, i know clyde the netbook should be named icarus. it was its original name. ironically the ssd burned out, and i felt it wasn't right when it came to reinstalling)

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• June 23, 1983: First Successful Test of the Domain Name System [Geek History]

  - by Jason Fitzpatrick

  Nearly 30 years ago the first Domain Name System (DNS) was tested and it changed the way we interacted with the internet. Nearly impossible to remember number addresses became easy to remember names. Without DNS you’d be browsing a web where numbered addresses pointed to numbered addresses. Google, for example, would look like http://209.85.148.105/ in your browser window. That’s assuming, of course, that a numbers-based web every gained enough traction to be popular enough to spawn a search giant like Google. How did this shift occur and what did we have before DNS? From Wikipedia: The practice of using a name as a simpler, more memorable abstraction of a host’s numerical address on a network dates back to the ARPANET era. Before the DNS was invented in 1983, each computer on the network retrieved a file called HOSTS.TXT from a computer at SRI. The HOSTS.TXT file mapped names to numerical addresses. A hosts file still exists on most modern operating systems by default and generally contains a mapping of the IP address 127.0.0.1 to “localhost”. Many operating systems use name resolution logic that allows the administrator to configure selection priorities for available name resolution methods. The rapid growth of the network made a centrally maintained, hand-crafted HOSTS.TXT file unsustainable; it became necessary to implement a more scalable system capable of automatically disseminating the requisite information. At the request of Jon Postel, Paul Mockapetris invented the Domain Name System in 1983 and wrote the first implementation. The original specifications were published by the Internet Engineering Task Force in RFC 882 and RFC 883, which were superseded in November 1987 by RFC 1034 and RFC 1035.Several additional Request for Comments have proposed various extensions to the core DNS protocols. Over the years it has been refined but the core of the system is essentially the same. When you type “google.com” into your web browser a DNS server is used to resolve that host name to the IP address of 209.85.148.105–making the web human-friendly in the process. Domain Name System History [Wikipedia via Wired] What is a Histogram, and How Can I Use it to Improve My Photos?How To Easily Access Your Home Network From Anywhere With DDNSHow To Recover After Your Email Password Is Compromised

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• Reporting on common code smells : A POC

  - by Dave Ballantyne

  Over the past few blog entries, I’ve been looking at parsing TSQL scripts in a variety of ways for a variety of tasks.  In my last entry ‘How to prevent ‘Select *’ : The elegant way’, I looked at parsing SQL to report upon uses of SELECT *.  The obvious question leading on from this is, “Great, what about other code smells ?”  Well, using the language service parser to do that was turning out to be a bit of a hard job,  sure I was getting tokens but no real context.  I wasn't even being told when an end of statement had been reached. One of the other parsing options available from Microsoft is exposed in the assembly ‘Microsoft.SqlServer.TransactSql.ScriptDom’,  this is ,I believe, installed with the client development tools with SQLServer.  It is much more feature rich than the original parser I had used and breaks a TSQL script into intuitive classes for analysis. So, what sort of smells can I now find using it ?  Well, for an opening gambit quite a nice little list. Use of NOLOCK Set of READ UNCOMMITTED Use of SELECT * Insert without column references Explicit datatype conversion on Sargs Cross server selects Non use of two-part naming convention Table and Query hint usage Changes in set options Use of single line comments Use of ordinal column positions in ORDER BY clause Now, lets not argue the point that “It depends” as smells on some of these, but as an academic exercise it is quite interesting.  The code is available from this link :https://www.dropbox.com/s/rfk32sou4fzl2cw/TSQLDomTest.zip  All the usual disclaimers apply to this code, I cannot be held responsible for anything ranging from mild annoyance through to universe destruction due to the use of this code or examples. The zip file contains a powershell script and my test cases.  The assembly used requires .Net 4 to run, which means that you will need powershell 3 ( though im running through PowerGUI and all works ok ) .  The code searches for all .sql files in the folder hierarchy for the workingpath,  you can override this if you want by simply changing the $Folder variable, and processes each in turn for the smells.  Feedback is not great at the moment, all it does is output to an xml file (Smells.xml) the offset position and a description of the smell found. Right now, I am interested in your feedback.  What do you think ?  Is this (or should it be) more than an academic exercise ?  Can tooling such as this be used as some form of code quality measure ?  Does it Work ? Do you have a case listed above which is not being reported ? Do you have a case that you would love to be reported ? Let me know , please mailto: [email protected]. Thanks

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• Is There a Real Advantage to Generic Repository?

  - by Sam

  Was reading through some articles on the advantages of creating Generic Repositories for a new app (example). The idea seems nice because it lets me use the same repository to do several things for several different entity types at once: IRepository repo = new EfRepository(); // Would normally pass through IOC into constructor var c1 = new Country() { Name = "United States", CountryCode = "US" }; var c2 = new Country() { Name = "Canada", CountryCode = "CA" }; var c3 = new Country() { Name = "Mexico", CountryCode = "MX" }; var p1 = new Province() { Country = c1, Name = "Alabama", Abbreviation = "AL" }; var p2 = new Province() { Country = c1, Name = "Alaska", Abbreviation = "AK" }; var p3 = new Province() { Country = c2, Name = "Alberta", Abbreviation = "AB" }; repo.Add<Country>(c1); repo.Add<Country>(c2); repo.Add<Country>(c3); repo.Add<Province>(p1); repo.Add<Province>(p2); repo.Add<Province>(p3); repo.Save(); However, the rest of the implementation of the Repository has a heavy reliance on Linq: IQueryable<T> Query(); IList<T> Find(Expression<Func<T,bool>> predicate); T Get(Expression<Func<T,bool>> predicate); T First(Expression<Func<T,bool>> predicate); //... and so on This repository pattern worked fantastic for Entity Framework, and pretty much offered a 1 to 1 mapping of the methods available on DbContext/DbSet. But given the slow uptake of Linq on other data access technologies outside of Entity Framework, what advantage does this provide over working directly with the DbContext? I attempted to write a PetaPoco version of the Repository, but PetaPoco doesn't support Linq Expressions, which makes creating a generic IRepository interface pretty much useless unless you only use it for the basic GetAll, GetById, Add, Update, Delete, and Save methods and utilize it as a base class. Then you have to create specific repositories with specialized methods to handle all the "where" clauses that I could previously pass in as a predicate. Is the Generic Repository pattern useful for anything outside of Entity Framework? If not, why would someone use it at all instead of working directly with Entity Framework? Edit: Original link doesn't reflect the pattern I was using in my sample code. Here is an (updated link).

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• Should a server "be lenient" in what it accepts and "discard faulty input silently"?

  - by romkyns

  I was under the impression that by now everyone agrees this maxim was a mistake. But I recently saw this answer which has a "be lenient" comment upvoted 137 times (as of today). In my opinion, the leniency in what browsers accept was the direct cause of the utter mess that HTML and some other web standards were a few years ago, and have only recently begun to properly crystallize out of that mess. The way I see it, being lenient in what you accept will lead to this. The second part of the maxim is "discard faulty input silently, without returning an error message unless this is required by the specification", and this feels borderline offensive. Any programmer who has banged their head on the wall when something fails silently will know what I mean. So, am I completely wrong about this? Should my program be lenient in what it accepts and swallow errors silently? Or am I mis-interpreting what this is supposed to mean? The original question said "program", and I take everyone's point about that. It can make sense for programs to be lenient. What I really meant, however, is APIs: interfaces exposed to other programs, rather than people. HTTP is an example. The protocol is an interface that only other programs use. People never directly provide the dates that go into headers like "If-Modified-Since". So, the question is: should the server implementing a standard be lenient and allow dates in several other formats, in addition to the one that's actually required by the standard? I believe the "be lenient" is supposed to apply to this situation, rather than human interfaces. If the server is lenient, it might seem like an overall improvement, but I think in practice it only leads to client implementations that end up relying on the leniency and thus failing to work with another server that's lenient in slightly different ways. So, should a server exposing some API be lenient or is that a very bad idea? Now onto lenient handling of user input. Consider YouTrack (a bug tracking software). It uses a language for text entry that is reminiscent of Markdown. Except that it's "lenient". For example, writing - foo - bar - baz is not a documented way of creating a bulleted list, and yet it worked. Consequently, it ended up being used a lot throughout our internal bugtracker. Next version comes out, and this lenient feature starts working slightly differently, breaking a bunch of lists that (mis)used this (non)feature. The documented way to create bulleted lists still works, of course. So, should my software be lenient in what user inputs it accepts?

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• Walmart's Mobile Self-Checkout

  - by David Dorf

  Reuters recently reported that Walmart was testing an iPhone-based self-checkout at a store near its headquarters.  Consumers scan items as they're placed in the physical basket, then the virtual basket is transferred to an existing self-checkout station where payment is tendered.  A very solid solution, but not exactly original. Before we go further, let's look at the possible cost savings for Walmart.  According to the article: Pushing more shoppers to scan their own items and make payments without the help of a cashier could save Wal-Mart millions of dollars, Chief Financial Officer Charles Holley said on March 7. The company spends about $12 million in cashier wages every second at its Walmart U.S. stores. Um, yeah. Using back-of-the-napkin math, I calculated Walmart's cashiers are making $157k per hour.  A more accurate statement would be saving $12M per year for each second saved on the average transaction time.  So if this self-checkout approach saves 2 seconds per transaction on average, Walmart would save $24M per year on labor.  Maybe.  Sometimes that savings will be used to do other tasks in the store, so it may not directly translate to less employees. When I saw this approach demonstrated in Sweden, there were a few differences, which may or may not be in Walmart's plans.  First, the consumers were identified based on their loyalty card.  In order to offset the inevitable shrink, retailers need to save on labor but also increase basket size, typically via in-aisle promotions.  As they scan items, retailers should target promos, and that's easier to do if you know some shopping history.  Last I checked, Walmart had no loyalty program. Second, at the self-checkout station consumers were randomly selected for an audit in which they must re-scan all the items just like you do at a typical self-checkout.  If you were found to be stealing, your ability to use the system can be revoked.  That's a tough one in the US, especially when the system goes wrong, either by mistake or by lying.  At least in my view, the Swedes are bit more trustworthy than the people of Walmart. So while I think the idea of mobile self-checkout has merit, perhaps its not right for Walmart.

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• Advice for how to handle company pride

  - by user17971

  We have this "amazing" little product using the latest development methodologies, components with all the bells and whistles. I took over this product maybe 6 months ago and struggled with it from day one. Even though it is supposedly is state of the art because of all its amazing structure, using dependency injections, inversion of control from the unity framework, hibernation and is domain driven in a .net mvvm xaml application to make it streamlined and modular. I knew from the moment I saw the monolith that it was going to be an uphill struggle for me. A lot of little code-bits scattered all around in neatly organized paradigms. Debugging is difficult, tracing the code is difficult, making new code is difficult, although some modifications is surprisinly easy but it doesn't out weight the problems I have with the code by a long shot. When I took over the project I was told that the new management console was ready for delivery and all I had to do was compile it and drop it. This was the beginning of a uphill struggle, our customer didn't agree at all that this was the functionality they had asked for so I had to do modifications to the program to their specifications. Since the project pretty much has been overdue since I took over it it has always been important that we didn't add or change much to the original system. I could modify the existing bits. fast forward until today where I finally completed all their comments and issues with the program but now I think that the users has opened their eyes (even though they saw this program many times) that they will be going backwards with this new system, that it will be much worse than the tool they got today (for a long time due to the fact that I'm the only resource on the project, project manager, tester, developer, integration specialist etc) My problem is that I lost faith in this system quite early due to the nature of the program. Although I made many changes and improvements to the system I wholeheartedly sympathize with the poor users who are going to start using this system. Its not nearly doing all the things it should do. I had this conversation internally with my boss where I told him what I thought about it, that if I were the customer I wouldn't have spent money developing it. So what do I do now? The system in ready, on a staging system and nobody likes it, its too slow and boring and does maybe do 50% of what they need it to do. Despite how much energy and working around the clock I've done to this project: I won't mind scrapping the system but we've spent much money (well my salaries) developing it and my company wants us to be proud of everything we do and advocate it. How will I tackle the contractor when he asks for advice? Surely I can tell him, this is what we agreed upon based on your use case scenarios, and be done with it? How will I inform my boss about this progress? He knows what I feel about it but I always get the feeling he let my criticism pass him by as just hot air, gone tomorrow,.

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• SmartOS reboots spontaneously

  - by Alex

  I run a SmartOS system on a Hetzner EX4S (Intel Core i7-2600, 32G RAM, 2x3Tb SATA HDD). There are six virtual machines on the host: [root@10-bf-48-7f-e7-03 ~]# vmadm list UUID TYPE RAM STATE ALIAS d2223467-bbe5-4b81-a9d1-439e9a66d43f KVM 512 running xxxx1 5f36358f-68fa-4351-b66f-830484b9a6ee KVM 1024 running xxxx2 d570e9ac-9eac-4e4f-8fda-2b1d721c8358 OS 1024 running xxxx3 ef88979e-fb7f-460c-bf56-905755e0a399 KVM 1024 running xxxx4 d8e06def-c9c9-4d17-b975-47dd4836f962 KVM 4096 running xxxx5 4b06fe88-db6e-4cf3-aadd-e1006ada7188 KVM 9216 running xxxx5 [root@10-bf-48-7f-e7-03 ~]# The host reboots several times a week with no crash dump in /var/crash and no messages in the /var/adm/messages log. Basically /var/adm/messages looks like there was a hard reset: 2012-11-23T08:54:43.210625+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T09:14:43.187589+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T09:34:43.165100+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T09:54:43.142065+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T10:14:43.119365+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T10:34:43.096351+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T10:54:43.073821+00:00 10-bf-48-7f-e7-03 rsyslogd: -- MARK -- 2012-11-23T10:57:55.610954+00:00 10-bf-48-7f-e7-03 genunix: [ID 540533 kern.notice] #015SunOS Release 5.11 Version joyent_20121018T224723Z 64-bit 2012-11-23T10:57:55.610962+00:00 10-bf-48-7f-e7-03 genunix: [ID 299592 kern.notice] Copyright (c) 2010-2012, Joyent Inc. All rights reserved. 2012-11-23T10:57:55.610967+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: lgpg 2012-11-23T10:57:55.610971+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: tsc 2012-11-23T10:57:55.610974+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: msr 2012-11-23T10:57:55.610978+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: mtrr 2012-11-23T10:57:55.610981+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: pge 2012-11-23T10:57:55.610984+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: de 2012-11-23T10:57:55.610987+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: cmov 2012-11-23T10:57:55.610995+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: mmx 2012-11-23T10:57:55.611000+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: mca 2012-11-23T10:57:55.611004+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: pae 2012-11-23T10:57:55.611008+00:00 10-bf-48-7f-e7-03 unix: [ID 223955 kern.info] x86_feature: cv8 The problem is that sometimes the host loses the network interface on reboot so we need to perform a manual hardware reset to bring it back. We do not have physical or virtual access to the server console - no KVM, no iLO or anything like this. So, the only way to debug is to analyze crash dumps/log files. I am not a SmartOS/Solaris expert so I am not sure how to proceed. Is there any equivalent of Linux netconsole for SmartOS? Can I just redirect the console output to the network port somehow? Maybe I am missing something obvious and crash information is located somewhere else.

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• Precise Touch Screen Dragging Issue: Trouble Aligning with the Finger due to Different Screen Resolution

  - by David Dimalanta

  Please, I need your help. I'm trying to make a game that will drag-n-drop a sprite/image while my finger follows precisely with the image without being offset. When I'm trying on a 900x1280 (in X [900] and Y [1280]) screen resolution of the Google Nexus 7 tablet, it follows precisely. However, if I try testing on a phone smaller than 900x1280, my finger and the image won't aligned properly and correctly except it still dragging. This is the code I used for making a sprite dragging with my finger under touchDragged(): x = ((screenX + Gdx.input.getX())/2) - (fruit.width/2); y = ((camera_2.viewportHeight * multiplier) - ((screenY + Gdx.input.getY())/2) - (fruit.width/2)); This code above will make the finger and the image/sprite stays together in place while dragging but only works on 900x1280. You'll be wondering there's camera_2.viewportHeight in my code. Here are for two reasons: to prevent inverted drag (e.g. when you swipe with your finger downwards, the sprite moves upward instead) and baseline for reading coordinate...I think. Now when I'm adding another orthographic camera named camera_1 and changing its setting, I recently used it for adjusting the falling object by meter per pixel. Also, it seems effective independently for smartphones that has smaller resolution and this is what I used here: show() camera_1 = new OrthographicCamera(); camera_1.viewportHeight = 280; // --> I set it to a smaller view port height so that the object would fall faster, decreasing the chance of drag force. camera_1.viewportWidth = 196; // --> Make it proportion to the original screen view size as possible. camera_1.position.set(camera_1.viewportWidth * 0.5f, camera_1.viewportHeight * 0.5f, 0f); camera_1.update(); touchDragged() x = ((screenX + (camera_1.viewportWidth/Gdx.input.getX()))/2) - (fruit.width/2); y = ((camera_1.viewportHeight * multiplier) - ((screenY + (camera_1.viewportHeight/Gdx.input.getY()))/2) - (fruit.width/2)); But the result instead of just following the image/sprite closely to my finger, it still has a space/gap between the sprite/image and the finger. It is possibly dependent on coordinates based on the screen resolution. I'm trying to drag the blueberry sprite with my finger. My expectation did not met since I want my finger and the sprite/image (blueberry) to stay close together while dragging until I release it. Here's what it looks like: I got to figure it out how to make independent on all screen sizes by just following the image/sprite closely to my finger while dragging even on most different screen sizes instead.

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• Problem with OpenGL or Unity, need Gnome fallback mode

  - by William Wind

  This question is in two parts, and I have been searching the web for days to find answers. With no luck I thought I'd drop by and ask for your help. Here goes: 1.) I'm running Ubuntu 13.04 and one day last week Unity suddenly wound't work. After the login screen, I was either faced with an all black and non-responsive screen, or sometimes it booted and I could see my desktop wallpaper (and add and remove icons/folders from the desktop). But there was no menu in the left hand side and no top bar :-( However I could still enter the terminal. I borrowed my dad's laptop and looked for a solution online. About two days later I gave up (I'm still kind of a n00b at Linux) and found a way to install Gnome Fallback, via the terminal. When I used it, I had the same problem. [clue #1] Missing menues. But if I rebooted into Gnome Fallback mode with no effects. It worked. Great! I have used that for some days now, while still trying to fix the original problem with either Unity or OpenGl or whatever went wrong in the first place. With no luck. After giving up on my search for a fix (I know that came out wrong) -- I decided to reinstall Ubuntu 13.04 from a CD. But! After that I was left where I began. When booting into my account, it only shows the desktop wallpaper and the icons. I can click and enter the folders, but not go into the menues. Last time I fixed it with Gnome Fallback mode, because I could enter the terminal and the PC was automatically online, via wireless network. But not this time, I can't get online. So: 1.) How do I via the LiveCD Ubuntu version (the one I'm using right now) install Gnome Fallback unto the harddrive based system? 2.) If impossible. How can I access the wireless Internet via the terminal, so I can install Gnome Fallback, from the "broken" Unity session. 3.) Is there any other things that I should try? Please help me, PS: My GFX-card is an ATI Radeon something and I have install and used the "Redwood" drive (I think its called) for many weeks prior to the shutdown.

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• More Maintenance Plan Weirdness

  - by AjarnMark

  I’m not a big fan of the built-in Maintenance Plan functionality in SQL Server.  I like the interface in SQL 2005 better than 2000 (it looks more like building an SSIS package) but it’s still a bit of a black box.  You don’t really know what commands are being run based on the selections you have made, and you can easily make some unwise choices without realizing it, such as shrinking your database on a regular basis.  I really prefer to know exactly what commands and with which options are being run on my servers. Recently I had another very strange thing happen with a Maintenance Plan, this time in SQL 2005, SP3.  I inherited this server and have done a bit of cleanup on it, but had not yet gotten around to replacing the Maintenance Plans with all my own scripts.  However, one of the maintenance plans which was just responsible for doing LOG backups was running more frequently than that system needed, and I thought I would just tweak the schedule a bit.  So I opened the Maintenance Plan and edited the properties of the Subplan, setting a new schedule, saved it and figured all was good to go.  But the next execution of the Scheduled Job that triggers the Maintenance Plan code failed with an error about the Owner of the job.  Specifically the error was, “Unable to determine if the owner (OldDomain\OldDBAUserID) of job MaintenancePlanName.Subplan has server access (reason: Could not obtain information about Windows NT group/user 'OldDomain\OldDBAUserID’..”  I was really confused because I had previously updated all of the jobs to have current accounts as the owners.  At first I thought it was just a fluke, but it happened on the next scheduled cycle so I investigated further and sure enough, that job had the old DBA’s account listed as the owner.  I fixed it and the job successfully ran to completion. Now, I don’t really like mysteries like that, so I did some more testing and verified that, sure enough, just editing the Subplan schedule and saving the Maintenance Job caused the Scheduled Job to be recreated with the old credentials.  I don’t know where it is getting those credentials, but I can only assume that it is the same as the original creator of the Maintenance Plan, and for some reason it insists on using that ID for the job owner.  I looked through the options in SSMA and could not find anything would let me easily set the value that I wanted it to use.  I suspect that if I did something like executing sp_changeobjectowner against the Maintenance Plan that it would use that new ID instead.  I’m sure that there is good reason that it works this way, but rather than mess around with it much more, I’m just going to spend my time rolling out my replacement scripts instead. Chalk this little hidden oddity up as yet one more reason I’m not a fan of Maintenance Plans.

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• Shelving &ndash; What is it &ndash; and more importantly, can it help me?

  - by Chris Skardon

  Since we shifted to TFS we’ve had the ability to perform what is known as ‘shelving’. Shelving (whilst not a wholly new topic in the world of SCC) is new to us, and didn’t exist in our previous SCC solution – SVN. Soo… what is it? What? Shelving is a way to check-in but not check-in your code. By shelving you submit a copy of your ‘pending changes’ to the SCC server, (which maintains a list of the shelvesets) and once that is done you can either continue working, or undo your changes, safe in the knowledge that a backup copy exists on the server. You can unshelve your code at any time and get back to the state you were when you shelved. Yer, that is great but why not just check it in?? Shelvesets don’t have to build. The shelveset you put in there could be entirely broken, or it might solve every bug in the system – shelves aren’t continuously integrated so you can shelve anything. Hmmmm… What else? Shelving allows us to do some pretty cool stuff that beforehand was quite frankly a pain. For instance – Gated Check-ins are implemented via the shelving mechanism, when code is checked-in, what you’re actually doing is shelving it, the Build Controller will build the shelveset with the original code and if it succeeds, the code will be committed, if it fails – well – it’s only you that has to fix the code :) Other nice features are things like the ability to share code you are working on… For example, if I was having trouble with a particular piece of code, I could shelve it, and then you (yes you) could then get that shelveset and check out the problem for yourself, and if you fix it?? Well – you could check-it in! Nice, but day-to-day shizzle? Let’s say you’ve been working on your project and your project manager comes over to you and says: “Hey, errr, bad times, there is an urgent bug we need you to fix, it needs to go out now!” (also for this to play out – we’ll need to assume you’re currently working in the 'release’ branch for another bug fix (maybe))… You could undo all your current changes (obviously you’ll probably backup your code using zip or something I imagine) fix the bug, then re-copy your backup over the top, or you could shelve and unshelve. Perhaps some other uses will awaken the shelver in you… :) Before each checkin – if you shelve, you no longer need to worry (if indeed you do) about resolving conflicts and mysteriously losing your code… Going home at night? Not checking in straight away? Why not shelve, this way – should the worst come to the worst and your local pc gives up, you can just get the shelveset onto another machine and be up and running in literally seconds minutes…

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• Using HBase or Cassandra for a token server

  - by crippy

  I've been trying to figure out how to use HBase/Cassandra for a token system we're re-implementing. I can probably squeeze quite a lot more from MySQL, but it just seems it has come to clinging on to the wrong tool for the task just because we know it well. Eventually will hit a wall (like happened to us in other areas). Naturally I started looking into possible NoSQL solutions. The prominent ones (at least in terms of buzz) are HBase and Cassandra. The story is more or less like this: A user can send a gift other users. Each gift has a list of recipients or is public in which case limited by number or expiration date For each gift sent we generate some token that uniquely identifies that gift. For each gift we track the list of potential recipients and their current status relating to that gift (accepted, declinded etc). A user can request to see all his currently pending gifts A can request a list of users he has sent a gift to today (used to limit number of gifts sent) Required the ability to "dump" or "ignore" expired gifts (x day old gifts are considered expired) There are some other requirements but I believe the above covers the essentials. How would I go and model that using HBase or Cassandra? Well, the wall was performance. A few 10s of millions of records per day over 2 tables kept for 2 weeks (wish I could have kept it for more but there was no way). The response times kept getting slower and slower until eventually we had to start cutting down number of days we kept data. Caching helps here but it's not an ideal solution since a big part of the ops are updates. Also, as I hinted in my original post. We use MySQL extensively. We know exactly what it can and can't do both in naive implementations followed by native partitioning and finally by horizontally sharding our dataset on the application level to reside on multiple DB nodes. It can be done, but that's not really what I'm trying to get from this. I asked a very specific question about designing a solution using a NoSQL solution since it's very hard to find examples for designs out there. Brainlag, not trying to come off as rude. I actually appreciate it a lot that you are the only one who even bothered to respond. but I see it over and over again. People ask questions and others assume they have no idea what they're talking about and give an irrelevant answer. Ignore RDBMS please. The question is about nosql.

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• How to remove the boundary effects arising due to zero padding in scipy/numpy fft?

  - by Omkar

  I have made a python code to smoothen a given signal using the Weierstrass transform, which is basically the convolution of a normalised gaussian with a signal. The code is as follows: #Importing relevant libraries from __future__ import division from scipy.signal import fftconvolve import numpy as np def smooth_func(sig, x, t= 0.002): N = len(x) x1 = x[-1] x0 = x[0] # defining a new array y which is symmetric around zero, to make the gaussian symmetric. y = np.linspace(-(x1-x0)/2, (x1-x0)/2, N) #gaussian centered around zero. gaus = np.exp(-y**(2)/t) #using fftconvolve to speed up the convolution; gaus.sum() is the normalization constant. return fftconvolve(sig, gaus/gaus.sum(), mode='same') If I run this code for say a step function, it smoothens the corner, but at the boundary it interprets another corner and smoothens that too, as a result giving unnecessary behaviour at the boundary. I explain this with a figure shown in the link below. Boundary effects This problem does not arise if we directly integrate to find convolution. Hence the problem is not in Weierstrass transform, and hence the problem is in the fftconvolve function of scipy. To understand why this problem arises we first need to understand the working of fftconvolve in scipy. The fftconvolve function basically uses the convolution theorem to speed up the computation. In short it says: convolution(int1,int2)=ifft(fft(int1)*fft(int2)) If we directly apply this theorem we dont get the desired result. To get the desired result we need to take the fft on a array double the size of max(int1,int2). But this leads to the undesired boundary effects. This is because in the fft code, if size(int) is greater than the size(over which to take fft) it zero pads the input and then takes the fft. This zero padding is exactly what is responsible for the undesired boundary effects. Can you suggest a way to remove this boundary effects? I have tried to remove it by a simple trick. After smoothening the function I am compairing the value of the smoothened signal with the original signal near the boundaries and if they dont match I replace the value of the smoothened func with the input signal at that point. It is as follows: i = 0 eps=1e-3 while abs(smooth[i]-sig[i])> eps: #compairing the signals on the left boundary smooth[i] = sig[i] i = i + 1 j = -1 while abs(smooth[j]-sig[j])> eps: # compairing on the right boundary. smooth[j] = sig[j] j = j - 1 There is a problem with this method, because of using an epsilon there are small jumps in the smoothened function, as shown below: jumps in the smooth func Can there be any changes made in the above method to solve this boundary problem?

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• Upgrading 10.04LTS -> 10.10 using custom sources

  - by Boatzart

  I'm trying to upgrade to 10.10 from 10.04 LTS using a custom sources.list file that points to an unofficial mirror*. The mirror does have maverick, but I get the following output when upgrading: boatzart@somecomputer: > sudo do-release-upgrade Checking for a new ubuntu release Done Upgrade tool signature Done Upgrade tool Done downloading extracting 'maverick.tar.gz' authenticate 'maverick.tar.gz' against 'maverick.tar.gz.gpg' tar: Removing leading `/' from member names Reading cache Checking package manager Reading package lists... Done Building dependency tree Reading state information... Done Building data structures... Done Reading package lists... Done Building dependency tree Reading state information... Done Building data structures... Done Updating repository information WARNING: Failed to read mirror file No valid mirror found While scanning your repository information no mirror entry for the upgrade was found. This can happen if you run a internal mirror or if the mirror information is out of date. Do you want to rewrite your 'sources.list' file anyway? If you choose 'Yes' here it will update all 'lucid' to 'maverick' entries. If you select 'No' the upgrade will cancel. Continue [yN] y WARNING: Failed to read mirror file 96% [Working] Checking package manager Reading package lists... Done Building dependency tree Reading state information... Done Building data structures... Done Calculating the changes Calculating the changes Could not calculate the upgrade An unresolvable problem occurred while calculating the upgrade: The package 'update-manager-kde' is marked for removal but it is in the removal blacklist. This can be caused by: * Upgrading to a pre-release version of Ubuntu * Running the current pre-release version of Ubuntu * Unofficial software packages not provided by Ubuntu If none of this applies, then please report this bug against the 'update-manager' package and include the files in /var/log/dist-upgrade/ in the bug report. Restoring original system state Aborting Reading package lists... Done Building dependency tree Reading state information... Done Building data structures... Done Here is the relevant section from /var/log/dist-upgrade/main.log: 2010-11-18 14:05:52,117 DEBUG The package 'update-manager-kde' is marked for removal but it's in the removal blacklist 2010-11-18 14:05:52,136 ERROR Dist-upgrade failed: 'The package 'update-manager-kde' is marked for removal but it is in the removal blacklist.' 2010-11-18 14:05:52,136 DEBUG abort called *I'm located inside of USC, and for some crazy reason any sustained downloads to anywhere outside of the University are throttled down to 5kbps inside of my lab. Because of this I need to use the following sources.list: deb http://mirrors.usc.edu/pub/linux/distributions/ubuntu/ lucid main restricted universe multiverse deb http://mirrors.usc.edu/pub/linux/distributions/ubuntu/ lucid-updates main restricted universe multiverse deb http://mirrors.usc.edu/pub/linux/distributions/ubuntu/ lucid-backports main restricted universe multiverse deb http://mirrors.usc.edu/pub/linux/distributions/ubuntu/ lucid-security main restricted universe multiverse I've tried adding four more entries to the sources.list with s/lucid/maverick/ but that didn't help. Does anyone know how to fix this? Thanks!

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