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  • jQuery and array of objects

    - by sepoto
    $(document).ready(function () { output = ""; $.ajax({ url: 'getevents.php', data: { ufirstname: 'ufirstname' }, type: 'post', success: function (output) { alert(output); var date = new Date(); var d = date.getDate(); var m = date.getMonth(); var y = date.getFullYear(); $('#calendar').fullCalendar({ header: { left: 'prev,next today', center: 'title', right: 'month,basicWeek,basicDay' }, editable: true, events: output }); } }); }); I have code like this and if I copy the text verbatim out of my alert box and replace events: output with events: [{ id: 1, title: 'Birthday', start: new Date(1355011200*1000), end: new Date(1355011200*1000), allDay: true, url: 'http://www.yahoo.com/'},{ id: 2, title: 'Birthday Hangover', start: new Date(1355097600*1000), end: new Date(1355097600*1000), allDay: false, url: 'http://www.yahoo.com'},{ id: 3, title: 'Sepotomus Maximus Christmas', start: new Date(1356393600*1000), end: new Date(1356393600*1000), allDay: false, url: 'http://www.yahoo.com/'},] Everything works just fine. What can I do to fix this problem? I though that using events: output would place the text in that location but it does not seem to be working. Thank you all kindly in advance for any comments or answers!

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  • JAVA - How to code Node neighbours in a Grid ?

    - by ke3pup
    Hi guys I'm new to programming and as a School task i need to implement BFS,DFS and A* search algorithms in java to search for a given Goal from a given start position in a Grid of given size, 4x4,8x8..etc to begin with i don't know how to code the neighbors of all the nodes. For example tile 1 in grid as 2 and 9 as neighbors and Tile 12 has ,141,13,20 as its neighbours but i'm struggling to code that. I need the neighbours part so that i can move from start position to other parts of gird legally by moving horizontally or vertically through the neighbours. my node class is: class node { int value; LinkedList neighbors; bool expanded; } let's say i'm given a 8x8 grid right, So if i start the program with a grid of size 8x8 right : 1 - my main will func will create an arrayList of nodes for example node ArrayList test = new ArrayList(); and then using a for loop assign value to all the nodes in arrayList from 1 to 64 (if the grid size was 8x8). BUT somehow i need t on coding that, if anyone can give me some details i would really appreciate it.

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  • What are some ways to accomplish a dynamic array?

    - by Ted
    I'm going to start working on a new game and one of the things I'd like to accomplish is a dynamic array sort of system that would hold map data. The game will be top-down 2d and made with XNA 4.0 and C#. You will begin in a randomized area which will essentially be tile based. As such a 2 dimensional array would be one way to accomplish this by holding numerical values which would correspond to a list of textures and that would be how it would draw this randomly created map. The problem is I would kind of only like to create the area around where you start and they could venture in which ever direction they wanted to. This would mean I'd have to populate the map array with more randomized data in the direction they go. I could make a really large array and use the center of it and the rest would be in anticipation of new content to be made, but that just seems very inefficient. I suppose when they start a new game I could have a one time map creation process that would go through and create a large randomly generated map array, but holding all of in memory at all times seems also inefficient. Perhaps if there was a way that I'd only hold parts of that map data in memory at one time and somehow not hold the rest in memory. In the end I only need to have a chunk of the map somewhat close to them in memory so perhaps some of you might have suggestions on good ways to approach this kind of randomized map and dynamic array problem. It wouldn't need to be a dynamic array type of thing if I made it so that it pulled in map data nearby that is needed and then once off the screen and not needed it could somehow get rid of that memory that way I wouldn't have a huge array taking up a bunch of memory.

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  • Access database Need to prevent from approving overlapping OT.Second Try with modified request Not a programmer [on hold]

    - by user2512764
    Employees Signups on company Website for advance overtime line. Access table already has overtime signups which does not require user to add the time but it requires only to add location as approved. Since this table has field Employee name, Date, start time and End time and location, All the fields has the data except for location. In the data base I have created a form based on this table. Since the table already have most of the information User only has to add location in the form field in order to approve overtime. Once user approves an overtime line for example: User approves overtime for employee name 'John' which starts on 7/1/2013 at 0400-0800, location is successfully added. When user tries to add location for John again which might has the start time for 7/1/2013 at 0600=0900. Again we are not entering Start time, End time and date it is already in the table. we are only entering location as approval. Soon user enters the location for John in the form field, since there is a conflict with previously overtime line which has already been approved. program needs to check employee name, date and time in previously approved (Added location) overtime line and The location in current record needs to be deleted and go to next record. I hope I have explained it in understandable format. Thank You,

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  • Windows 2008 and wrong BPL loading [SOLVED]

    - by Beto Neto
    I have an application builded with Run-time Packages. When the executable starts it auto loads the required packages (.bpl). Recently we has installed an Windows 2008 R2 server to use as Terminal Services. We maintain some old compiled versions of our application in different paths, like this: c:\app\version_1\common.bpl c:\app\version_1\app.exe c:\app\version_2\common.bpl c:\app\version_2\app.exe Common.bpl is the a run-time package what app.exe depends on. THE PROBLEM: I start "c:\app\version_2\app.exe" and it loads "c:\app\version_2\common.bpl". When I start the "c:\app\version_1\app.exe" it loads the WRONG bpl (from version_2). The path "c:\app\version_2\" isn't at the system search path. At Windows2003 server this problem doesn't occurs. What can I do to solve this? Thanks! I have downloaded the Process Explorer (microsoft sysinternals), and checked the loaded modules of each executable, all they are correct! But I noticed another problem. After start the second version, an entry-not-found-error occurs, telling me what a initialization entry point, of an unit what only exists in one of the versions, could not be found. Something is very strange. The ProcessExplorer is telling me that the process is loading the correct modoles, but when they are running this seems not be happening. Seems the applications are sharing the loaded modules. SOLVED There was a MouseHook using FindVCLWindow, this was generating the AV. Sorry about inconvenience guys, and thanks!

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  • PHP- Display days weekly by giving 2 dates

    - by librium
    I'd like display dates by week number between giving 2 dates like example below. Is this possible in PHP? if the dates are 2010-12-01 thru 2010-12-19, it will display it as follows. week-1 2010-12-01 2010-12-02 2010-12-03 2010-12-04 2010-12-05 2010-12-06 2010-12-07 week-2 2010-12-08 2010-12-09 2010-12-10 2010-12-11 2010-12-12 2010-12-13 2010-12-14 week-3 2010-12-15 2010-12-16 2010-12-17 2010-12-18 2010-12-19 and so on... I use mysql. It has startdate end enddate fields. thank you in advance. I can get how many weeks in those giving 2 dates and display them using a datediff('ww', '2010-12-01', '2010-12-19', false); I found on the internet. And I can display dates between two dates as follows. But I am having trouble grouping them by week. $sdate = "2010-12-01"; $edate = "2010-12-19"; $days = getDaysInBetween($sdate, $edate); foreach ($days as $val) { echo $val; } function getDaysInBetween($start, $end) { // Vars $day = 86400; // Day in seconds $format = 'Y-m-d'; // Output format (see PHP date funciton) $sTime = strtotime($start); // Start as time $eTime = strtotime($end); // End as time $numDays = round(($eTime - $sTime) / $day) + 1; $days = array(); // Get days for ($d = 0; $d < $numDays; $d++) { $days[] = date($format, ($sTime + ($d * $day))); } // Return days return $days; }

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  • Install uTorrent

    - by Milkncookiez
    I followed these 2 tuts: Step by step installation Stuff if you are with x64 OS Well, I am done until the pre-last step. I have created the symlink, and when I navigate to the folder .../opt/utorrent-server-v3_0 I can see the utserver file. But when I run the command utserver -settingspath /opt/utorrent-server-v3_0/ Therefore I cannot open the localhost:8080/gui/... Any ideas what might be the problem and how to proceed?

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  • MAAS nodes stuck on "maas-enlisting-node"

    - by CyberJacob
    I am trying to set up an MAAS cluster, but am having some issues adding nodes. The nodes boot up from the TFTP server on the master server, display a login screen (with the hostname "maas-enlisting-node") and stop. I cannot log in with ubuntu/ubuntu or with my SSH keys. The MAAS server is running DHCP and DNS on the network, and the TFTP boot appears to be loading everything without issues (I can screencap if you want) Any ideas what's going wrong? Thanks!

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  • How do I install axis2 into tomcat6 on 10.04?

    - by spinlock
    I'm trying to install axis2 onto tomcat6 and I'm having some difficulties. I've installed tomcat6 using apt and I've downloaded the axis2.war file and placed it in /usr/share/tomcat6/webapps/. From the instructions I'm following, tomcat should now unpack the war file and create and axis2 directory in webapps/ but this is not happening. I can see the default tomcat page on http://localhost:8080/ but I cannot see the axis2 page on http://localhost:8080/axis2/ Any help would be greatly appreciated.

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  • Adobe Flash not working in 12.04

    - by catnthehat
    I cannot get Adobe Flash working in either Firefox or Chrome. I have tried the Flash-Aid plug in for Firefox but it has not made any difference. As far as I can see, Flash installs without error and Firefox thinks it can run Flash but (for example) YouTube just shows a blank square where the movie should be me. Chrome reports "missing plugin". about:plugins in Firefox reports: Shockwave Flash File: libflashplayer.so Version: Shockwave Flash 11.2 r202 MIME Type Description Suffixes application/x-shockwave-flash Shockwave Flash swf application/futuresplash FutureSplash Player spl

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  • Another "Windows 7 entry missing from Grub2" Question

    - by 4x10
    Like many before me had the following problem that after installing Ubuntu (with windows 7 already installed), the grub boot loader wouldnt show windows 7 as a boot option, though i can boot fine if I use the "Choose Boot Device" options on the x220. The difference is that I try using UEFI only so many answers didn't really fit my problem, though i tried several stuffs: after running boot repair it destroyed the ubuntu boot loader custom entry in /etc/grub.d/40_custom for windows which doesnt show up many update-grub and reboots trying windows repair recovery thing while being there i also did bootrec.exe /FixBoot and update-grub and reboot again and finaly because it was so much fun, i installed linux all over again, while formatting and deleting everything linux related before that. Now that i think of it, Ubuntu also didn't notice Windows being there during the Setup and it still doesnt according to the Boot Info from Boot Repair. Boot Info Script 0.61-git-patched [23 April 2012] ============================= Boot Info Summary: =============================== => No boot loader is installed in the MBR of /dev/sda. sda1: __________________________________________________________________________ File system: vfat Boot sector type: Windows 7: FAT32 Boot sector info: No errors found in the Boot Parameter Block. Operating System: Boot files: /efi/Boot/bootx64.efi /efi/ubuntu/grubx64.efi sda2: __________________________________________________________________________ File system: Boot sector type: - Boot sector info: Mounting failed: mount: unknown filesystem type '' sda3: __________________________________________________________________________ File system: ntfs Boot sector type: Windows Vista/7: NTFS Boot sector info: No errors found in the Boot Parameter Block. Operating System: Windows 7 Boot files: /Windows/System32/winload.exe sda4: __________________________________________________________________________ File system: ext4 Boot sector type: - Boot sector info: Operating System: Ubuntu precise (development branch) Boot files: /boot/grub/grub.cfg /etc/fstab sda5: __________________________________________________________________________ File system: ext4 Boot sector type: - Boot sector info: Operating System: Boot files: sda6: __________________________________________________________________________ File system: swap Boot sector type: - Boot sector info: ============================ Drive/Partition Info: ============================= Drive: sda _____________________________________________________________________ Disk /dev/sda: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes Partition Boot Start Sector End Sector # of Sectors Id System /dev/sda1 1 625,142,447 625,142,447 ee GPT GUID Partition Table detected. Partition Start Sector End Sector # of Sectors System /dev/sda1 2,048 206,847 204,800 EFI System partition /dev/sda2 206,848 468,991 262,144 Microsoft Reserved Partition (Windows) /dev/sda3 468,992 170,338,303 169,869,312 Data partition (Windows/Linux) /dev/sda4 170,338,304 330,338,304 160,000,001 Data partition (Windows/Linux) /dev/sda5 330,338,305 617,141,039 286,802,735 Data partition (Windows/Linux) /dev/sda6 617,141,040 625,141,040 8,000,001 Swap partition (Linux) "blkid" output: ________________________________________________________________ Device UUID TYPE LABEL /dev/sda1 885C-ED1B vfat /dev/sda3 EE06CC0506CBCCB1 ntfs /dev/sda4 604dd3b2-64ca-4200-b8fb-820e8d0ca899 ext4 /dev/sda5 d62515fd-8120-4a74-b17b-0bdf244124a3 ext4 /dev/sda6 7078b649-fb2a-4c59-bd03-fd31ef440d37 swap ================================ Mount points: ================================= Device Mount_Point Type Options /dev/sda1 /boot/efi vfat (rw) /dev/sda4 / ext4 (rw,errors=remount-ro) /dev/sda5 /home ext4 (rw) =========================== sda4/boot/grub/grub.cfg: =========================== -------------------------------------------------------------------------------- # # DO NOT EDIT THIS FILE # # It is automatically generated by grub-mkconfig using templates # from /etc/grub.d and settings from /etc/default/grub # ### BEGIN /etc/grub.d/00_header ### if [ -s $prefix/grubenv ]; then set have_grubenv=true load_env fi set default="0" if [ "${prev_saved_entry}" ]; then set saved_entry="${prev_saved_entry}" save_env saved_entry set prev_saved_entry= save_env prev_saved_entry set boot_once=true fi function savedefault { if [ -z "${boot_once}" ]; then saved_entry="${chosen}" save_env saved_entry fi } function recordfail { set recordfail=1 if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi } function load_video { insmod efi_gop insmod efi_uga insmod video_bochs insmod video_cirrus } insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 if loadfont /usr/share/grub/unicode.pf2 ; then set gfxmode=auto load_video insmod gfxterm insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 set locale_dir=($root)/boot/grub/locale set lang=en_US insmod gettext fi terminal_output gfxterm if [ "${recordfail}" = 1 ]; then set timeout=-1 else set timeout=10 fi ### END /etc/grub.d/00_header ### ### BEGIN /etc/grub.d/05_debian_theme ### set menu_color_normal=white/black set menu_color_highlight=black/light-gray if background_color 44,0,30; then clear fi ### END /etc/grub.d/05_debian_theme ### ### BEGIN /etc/grub.d/10_linux ### function gfxmode { set gfxpayload="$1" if [ "$1" = "keep" ]; then set vt_handoff=vt.handoff=7 else set vt_handoff= fi } if [ ${recordfail} != 1 ]; then if [ -e ${prefix}/gfxblacklist.txt ]; then if hwmatch ${prefix}/gfxblacklist.txt 3; then if [ ${match} = 0 ]; then set linux_gfx_mode=keep else set linux_gfx_mode=text fi else set linux_gfx_mode=text fi else set linux_gfx_mode=keep fi else set linux_gfx_mode=text fi export linux_gfx_mode if [ "$linux_gfx_mode" != "text" ]; then load_video; fi menuentry 'Ubuntu, with Linux 3.2.0-20-generic' --class ubuntu --class gnu-linux --class gnu --class os { recordfail gfxmode $linux_gfx_mode insmod gzio insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 linux /boot/vmlinuz-3.2.0-20-generic root=UUID=604dd3b2-64ca-4200-b8fb-820e8d0ca899 ro quiet splash $vt_handoff initrd /boot/initrd.img-3.2.0-20-generic } menuentry 'Ubuntu, with Linux 3.2.0-20-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod gzio insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 echo 'Loading Linux 3.2.0-20-generic ...' linux /boot/vmlinuz-3.2.0-20-generic root=UUID=604dd3b2-64ca-4200-b8fb-820e8d0ca899 ro recovery nomodeset echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.2.0-20-generic } ### END /etc/grub.d/10_linux ### ### BEGIN /etc/grub.d/20_linux_xen ### ### END /etc/grub.d/20_linux_xen ### ### BEGIN /etc/grub.d/20_memtest86+ ### menuentry "Memory test (memtest86+)" { insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 linux16 /boot/memtest86+.bin } menuentry "Memory test (memtest86+, serial console 115200)" { insmod part_gpt insmod ext2 set root='(hd0,gpt4)' search --no-floppy --fs-uuid --set=root 604dd3b2-64ca-4200-b8fb-820e8d0ca899 linux16 /boot/memtest86+.bin console=ttyS0,115200n8 } ### END /etc/grub.d/20_memtest86+ ### ### BEGIN /etc/grub.d/30_os-prober ### ### END /etc/grub.d/30_os-prober ### ### BEGIN /etc/grub.d/40_custom ### # This file provides an easy way to add custom menu entries. Simply type the # menu entries you want to add after this comment. Be careful not to change # the 'exec tail' line above. ### END /etc/grub.d/40_custom ### ### BEGIN /etc/grub.d/41_custom ### if [ -f $prefix/custom.cfg ]; then source $prefix/custom.cfg; fi ### END /etc/grub.d/41_custom ### -------------------------------------------------------------------------------- =============================== sda4/etc/fstab: ================================ -------------------------------------------------------------------------------- # /etc/fstab: static file system information. # # Use 'blkid' to print the universally unique identifier for a # device; this may be used with UUID= as a more robust way to name devices # that works even if disks are added and removed. See fstab(5). # # <file system> <mount point> <type> <options> <dump> <pass> proc /proc proc nodev,noexec,nosuid 0 0 # / was on /dev/sda4 during installation UUID=604dd3b2-64ca-4200-b8fb-820e8d0ca899 / ext4 errors=remount-ro 0 1 # /boot/efi was on /dev/sda1 during installation UUID=885C-ED1B /boot/efi vfat defaults 0 1 # /home was on /dev/sda5 during installation UUID=d62515fd-8120-4a74-b17b-0bdf244124a3 /home ext4 defaults 0 2 # swap was on /dev/sda6 during installation UUID=7078b649-fb2a-4c59-bd03-fd31ef440d37 none swap sw 0 0 -------------------------------------------------------------------------------- =================== sda4: Location of files loaded by Grub: ==================== GiB - GB File Fragment(s) 129.422874451 = 138.966753280 boot/grub/grub.cfg 1 83.059570312 = 89.184534528 boot/initrd.img-3.2.0-20-generic 2 101.393131256 = 108.870045696 boot/vmlinuz-3.2.0-20-generic 1 83.059570312 = 89.184534528 initrd.img 2 101.393131256 = 108.870045696 vmlinuz 1 ADDITIONAL INFORMATION : =================== log of boot-repair 2012-04-25__23h40 =================== boot-repair version : 3.18-0ppa3~precise boot-sav version : 3.18-0ppa4~precise glade2script version : 0.3.2.1-0ppa7~precise internet: connected python-software-properties version : 0.82.7 0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 591 not upgraded. dpkg-preconfigure: unable to re-open stdin: No such file or directory boot-repair is executed in installed-session (Ubuntu precise (development branch) , precise , Ubuntu , x86_64) WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. =================== OSPROBER: /dev/sda4:The OS now in use - Ubuntu precise (development branch) CurrentSession:linux =================== BLKID: /dev/sda3: UUID="EE06CC0506CBCCB1" TYPE="ntfs" /dev/sda1: UUID="885C-ED1B" TYPE="vfat" /dev/sda4: UUID="604dd3b2-64ca-4200-b8fb-820e8d0ca899" TYPE="ext4" /dev/sda5: UUID="d62515fd-8120-4a74-b17b-0bdf244124a3" TYPE="ext4" /dev/sda6: UUID="7078b649-fb2a-4c59-bd03-fd31ef440d37" TYPE="swap" 1 disks with OS, 1 OS : 1 Linux, 0 MacOS, 0 Windows, 0 unknown type OS. WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util sfdisk doesn't support GPT. Use GNU Parted. =================== /etc/default/grub : # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 #GRUB_HIDDEN_TIMEOUT=0 #GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX="" # Uncomment to enable BadRAM filtering, modify to suit your needs # This works with Linux (no patch required) and with any kernel that obtains # the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...) #GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef" # Uncomment to disable graphical terminal (grub-pc only) #GRUB_TERMINAL=console # The resolution used on graphical terminal # note that you can use only modes which your graphic card supports via VBE # you can see them in real GRUB with the command `vbeinfo' #GRUB_GFXMODE=640x480 # Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux #GRUB_DISABLE_LINUX_UUID=true # Uncomment to disable generation of recovery mode menu entries #GRUB_DISABLE_RECOVERY="true" # Uncomment to get a beep at grub start #GRUB_INIT_TUNE="480 440 1" EFI_OF_PART[1] (, ) =================== dmesg | grep EFI : [ 0.000000] EFI v2.00 by Lenovo [ 0.000000] Kernel-defined memdesc doesn't match the one from EFI! [ 0.000000] EFI: mem00: type=3, attr=0xf, range=[0x0000000000000000-0x0000000000001000) (0MB) [ 0.000000] EFI: mem01: type=7, attr=0xf, range=[0x0000000000001000-0x000000000004e000) (0MB) [ 0.000000] EFI: mem02: type=3, attr=0xf, range=[0x000000000004e000-0x0000000000058000) (0MB) [ 0.000000] EFI: mem03: type=10, attr=0xf, range=[0x0000000000058000-0x0000000000059000) (0MB) [ 0.000000] EFI: mem04: type=7, attr=0xf, range=[0x0000000000059000-0x000000000005e000) (0MB) [ 0.000000] EFI: mem05: type=4, attr=0xf, range=[0x000000000005e000-0x000000000005f000) (0MB) [ 0.000000] EFI: mem06: type=3, attr=0xf, range=[0x000000000005f000-0x00000000000a0000) (0MB) [ 0.000000] EFI: mem07: type=2, attr=0xf, range=[0x0000000000100000-0x00000000005b9000) (4MB) [ 0.000000] EFI: mem08: type=7, attr=0xf, range=[0x00000000005b9000-0x0000000020000000) (506MB) [ 0.000000] EFI: mem09: type=0, attr=0xf, range=[0x0000000020000000-0x0000000020200000) (2MB) [ 0.000000] EFI: mem10: type=7, attr=0xf, range=[0x0000000020200000-0x00000000364e4000) (354MB) [ 0.000000] EFI: mem11: type=2, attr=0xf, range=[0x00000000364e4000-0x000000003726a000) (13MB) [ 0.000000] EFI: mem12: type=7, attr=0xf, range=[0x000000003726a000-0x0000000040000000) (141MB) [ 0.000000] EFI: mem13: type=0, attr=0xf, range=[0x0000000040000000-0x0000000040200000) (2MB) [ 0.000000] EFI: mem14: type=7, attr=0xf, range=[0x0000000040200000-0x000000009df35000) (1501MB) [ 0.000000] EFI: mem15: type=2, attr=0xf, range=[0x000000009df35000-0x00000000d39a0000) (858MB) [ 0.000000] EFI: mem16: type=4, attr=0xf, range=[0x00000000d39a0000-0x00000000d39c0000) (0MB) [ 0.000000] EFI: mem17: type=7, attr=0xf, range=[0x00000000d39c0000-0x00000000d5df5000) (36MB) [ 0.000000] EFI: mem18: type=4, attr=0xf, range=[0x00000000d5df5000-0x00000000d6990000) (11MB) [ 0.000000] EFI: mem19: type=7, attr=0xf, range=[0x00000000d6990000-0x00000000d6b82000) (1MB) [ 0.000000] EFI: mem20: type=1, attr=0xf, range=[0x00000000d6b82000-0x00000000d6b9f000) (0MB) [ 0.000000] EFI: mem21: type=7, attr=0xf, range=[0x00000000d6b9f000-0x00000000d77b0000) (12MB) [ 0.000000] EFI: mem22: type=4, attr=0xf, range=[0x00000000d77b0000-0x00000000d780a000) (0MB) [ 0.000000] EFI: mem23: type=7, attr=0xf, range=[0x00000000d780a000-0x00000000d7826000) (0MB) [ 0.000000] EFI: mem24: type=4, attr=0xf, range=[0x00000000d7826000-0x00000000d7868000) (0MB) [ 0.000000] EFI: mem25: type=7, attr=0xf, range=[0x00000000d7868000-0x00000000d7869000) (0MB) [ 0.000000] EFI: mem26: type=4, attr=0xf, range=[0x00000000d7869000-0x00000000d786a000) (0MB) [ 0.000000] EFI: mem27: type=7, attr=0xf, range=[0x00000000d786a000-0x00000000d786b000) (0MB) [ 0.000000] EFI: mem28: type=4, attr=0xf, range=[0x00000000d786b000-0x00000000d786c000) (0MB) [ 0.000000] EFI: mem29: type=7, attr=0xf, range=[0x00000000d786c000-0x00000000d786d000) (0MB) [ 0.000000] EFI: mem30: type=4, attr=0xf, range=[0x00000000d786d000-0x00000000d825f000) (9MB) [ 0.000000] EFI: mem31: type=7, attr=0xf, range=[0x00000000d825f000-0x00000000d8261000) (0MB) [ 0.000000] EFI: mem32: type=4, attr=0xf, range=[0x00000000d8261000-0x00000000d82f7000) (0MB) [ 0.000000] EFI: mem33: type=7, attr=0xf, range=[0x00000000d82f7000-0x00000000d82f8000) (0MB) [ 0.000000] EFI: mem34: type=4, attr=0xf, range=[0x00000000d82f8000-0x00000000d8705000) (4MB) [ 0.000000] EFI: mem35: type=7, attr=0xf, range=[0x00000000d8705000-0x00000000d8706000) (0MB) [ 0.000000] EFI: mem36: type=4, attr=0xf, range=[0x00000000d8706000-0x00000000d8761000) (0MB) [ 0.000000] EFI: mem37: type=7, attr=0xf, range=[0x00000000d8761000-0x00000000d8768000) (0MB) [ 0.000000] EFI: mem38: type=4, attr=0xf, range=[0x00000000d8768000-0x00000000d9b9f000) (20MB) [ 0.000000] EFI: mem39: type=7, attr=0xf, range=[0x00000000d9b9f000-0x00000000d9e4c000) (2MB) [ 0.000000] EFI: mem40: type=2, attr=0xf, range=[0x00000000d9e4c000-0x00000000d9e52000) (0MB) [ 0.000000] EFI: mem41: type=3, attr=0xf, range=[0x00000000d9e52000-0x00000000da59f000) (7MB) [ 0.000000] EFI: mem42: type=5, attr=0x800000000000000f, range=[0x00000000da59f000-0x00000000da6c3000) (1MB) [ 0.000000] EFI: mem43: type=5, attr=0x800000000000000f, range=[0x00000000da6c3000-0x00000000da79f000) (0MB) [ 0.000000] EFI: mem44: type=6, attr=0x800000000000000f, range=[0x00000000da79f000-0x00000000da8b1000) (1MB) [ 0.000000] EFI: mem45: type=6, attr=0x800000000000000f, range=[0x00000000da8b1000-0x00000000da99f000) (0MB) [ 0.000000] EFI: mem46: type=0, attr=0xf, range=[0x00000000da99f000-0x00000000daa22000) (0MB) [ 0.000000] EFI: mem47: type=0, attr=0xf, range=[0x00000000daa22000-0x00000000daa9b000) (0MB) [ 0.000000] EFI: mem48: type=0, attr=0xf, range=[0x00000000daa9b000-0x00000000daa9c000) (0MB) [ 0.000000] EFI: mem49: type=0, attr=0xf, range=[0x00000000daa9c000-0x00000000daa9f000) (0MB) [ 0.000000] EFI: mem50: type=10, attr=0xf, range=[0x00000000daa9f000-0x00000000daadd000) (0MB) [ 0.000000] EFI: mem51: type=10, attr=0xf, range=[0x00000000daadd000-0x00000000dab9f000) (0MB) [ 0.000000] EFI: mem52: type=9, attr=0xf, range=[0x00000000dab9f000-0x00000000dabdc000) (0MB) [ 0.000000] EFI: mem53: type=9, attr=0xf, range=[0x00000000dabdc000-0x00000000dabff000) (0MB) [ 0.000000] EFI: mem54: type=4, attr=0xf, range=[0x00000000dabff000-0x00000000dac00000) (0MB) [ 0.000000] EFI: mem55: type=7, attr=0xf, range=[0x0000000100000000-0x000000021e600000) (4582MB) [ 0.000000] EFI: mem56: type=11, attr=0x8000000000000001, range=[0x00000000f80f8000-0x00000000f80f9000) (0MB) [ 0.000000] EFI: mem57: type=11, attr=0x8000000000000001, range=[0x00000000fed1c000-0x00000000fed20000) (0MB) [ 0.000000] ACPI: UEFI 00000000dabde000 0003E (v01 LENOVO TP-8D 00001280 PTL 00000002) [ 0.000000] ACPI: UEFI 00000000dabdd000 00042 (v01 PTL COMBUF 00000001 PTL 00000001) [ 0.000000] ACPI: UEFI 00000000dabdc000 00292 (v01 LENOVO TP-8D 00001280 PTL 00000002) [ 0.795807] fb0: EFI VGA frame buffer device [ 1.057243] EFI Variables Facility v0.08 2004-May-17 [ 9.122104] fb: conflicting fb hw usage inteldrmfb vs EFI VGA - removing generic driver ReadEFI: /dev/sda , N 128 , 0 , , PRStart 1024 , PRSize 128 WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. =================== PARTITIONS & DISKS: sda4 : sda, not-sepboot, grubenv-ok grub2, grub-efi, update-grub, 64, with-boot, is-os, gpt-but-not-EFI, fstab-has-bad-efi, no-nt, no-winload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, apt-get, grub-install, . sda3 : sda, maybesepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, gpt-but-not-EFI, part-has-no-fstab, no-nt, haswinload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, nopakmgr, nogrubinstall, /mnt/boot-sav/sda3. sda1 : sda, maybesepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, is-correct-EFI, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, nopakmgr, nogrubinstall, /boot/efi. sda5 : sda, maybesepboot, no-grubenv nogrub, no-docgrub, no-update-grub, 32, no-boot, no-os, gpt-but-not-EFI, part-has-no-fstab, no-nt, no-winload, no-recov-nor-hid, no-bmgr, no-grldr, no-b-bcd, nopakmgr, nogrubinstall, /home. sda : GPT-BIS, GPT, no-BIOS_boot, has-correctEFI, 2048 sectors * 512 bytes =================== PARTED: Model: ATA HITACHI HTS72323 (scsi) Disk /dev/sda: 320GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 106MB 105MB fat32 EFI system partition boot 2 106MB 240MB 134MB Microsoft reserved partition msftres 3 240MB 87.2GB 87.0GB ntfs Basic data partition 4 87.2GB 169GB 81.9GB ext4 5 169GB 316GB 147GB ext4 6 316GB 320GB 4096MB linux-swap(v1) =================== MOUNT: /dev/sda4 on / type ext4 (rw,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) none on /sys/fs/fuse/connections type fusectl (rw) none on /sys/kernel/debug type debugfs (rw) none on /sys/kernel/security type securityfs (rw) udev on /dev type devtmpfs (rw,mode=0755) devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620) tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755) none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880) none on /run/shm type tmpfs (rw,nosuid,nodev) /dev/sda1 on /boot/efi type vfat (rw) /dev/sda5 on /home type ext4 (rw) gvfs-fuse-daemon on /home/vierlex/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev,user=vierlex) /dev/sda3 on /mnt/boot-sav/sda3 type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) /sys/block/sda: alignment_offset bdi capability dev device discard_alignment events events_async events_poll_msecs ext_range holders inflight power queue range removable ro sda1 sda2 sda3 sda4 sda5 sda6 size slaves stat subsystem trace uevent /dev: agpgart autofs block bsg btrfs-control bus char console core cpu cpu_dma_latency disk dri ecryptfs fb0 fd full fuse hpet input kmsg log mapper mcelog mei mem net network_latency network_throughput null oldmem port ppp psaux ptmx pts random rfkill rtc rtc0 sda sda1 sda2 sda3 sda4 sda5 sda6 sg0 shm snapshot snd stderr stdin stdout tpm0 uinput urandom usbmon0 usbmon1 usbmon2 v4l vga_arbiter video0 watchdog zero /dev/mapper: control /boot/efi: EFI /boot/efi/EFI: Boot Microsoft ubuntu /boot/efi/efi: Boot Microsoft ubuntu /boot/efi/efi/Boot: bootx64.efi /boot/efi/efi/ubuntu: grubx64.efi WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. =================== DF: Filesystem Type Size Used Avail Use% Mounted on /dev/sda4 ext4 77G 4.1G 69G 6% / udev devtmpfs 3.9G 12K 3.9G 1% /dev tmpfs tmpfs 1.6G 864K 1.6G 1% /run none tmpfs 5.0M 0 5.0M 0% /run/lock none tmpfs 3.9G 152K 3.9G 1% /run/shm /dev/sda1 vfat 96M 18M 79M 19% /boot/efi /dev/sda5 ext4 137G 2.2G 128G 2% /home /dev/sda3 fuseblk 81G 30G 52G 37% /mnt/boot-sav/sda3 =================== FDISK: Disk /dev/sda: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xf34fe538 Device Boot Start End Blocks Id System /dev/sda1 1 625142447 312571223+ ee GPT =================== Before mainwindow FSCK no PASTEBIN yes WUBI no WINBOOT yes recommendedrepair, purge, QTY_OF_PART_FOR_REINSTAL 1 no-kernel-purge UNHIDEBOOT_ACTION yes (10s), noflag () PART_TO_REINSTALL_GRUB sda4, FORCE_GRUB no (sda) REMOVABLEDISK no USE_SEPARATEBOOTPART no (sda3) grub2 () UNCOMMENT_GFXMODE no ATA ADD_KERNEL_OPTION no (acpi=off) MBR_TO_RESTORE ( ) EFI detected. Please check the options. =================== Actions FSCK no PASTEBIN yes WUBI no WINBOOT no bootinfo, nombraction, QTY_OF_PART_FOR_REINSTAL 1 no-kernel-purge UNHIDEBOOT_ACTION no (10s), noflag () PART_TO_REINSTALL_GRUB sda4, FORCE_GRUB no (sda) REMOVABLEDISK no USE_SEPARATEBOOTPART no (sda3) grub2 () UNCOMMENT_GFXMODE no ATA ADD_KERNEL_OPTION no (acpi=off) MBR_TO_RESTORE ( ) No change has been performed on your computer. See you soon! internet: connected Thanks for your time and attention. EDIT: additional Info Request =No boot loader is installed in the MBR of /dev/sda. But maybe this is how it is supposed to work? yea this is ok. boot stuff seems to be on a seperate partition, in my case sda1. I'm very new to this UEFI thing too. missing files like bootmgr i don't really have a clue :D but yea, maybe thats how it suppose to be? Instead and whats not shown in the log for some reason: There is additional microsoft bootfiles on sda1 under /efi/microsoft/ [much stuff] I remember also doing some kind of hack to make a UEFI windows 7 usb stick. http://jake.io/b/2011/installing-windows-7-with-uefi-boot-on-an-x220-from-usb/ In short: creating and placing bootx64.efi on the stick so it can be booted in UEFI mode. boot order i decide that in my BIOS. i read somwhere that the thinkpad x220 (essential part of the serial number: 4921 http://www.lenovo.com/shop/americas/content/user_guides/x220_x220i_x220tablet_x220itablet_ug_en.pdf) doesnt really have UEFI interface or something, still, these 2 options are listed with all the other usual devices you can give a boot priority to. Right now it looks like this: Boot Priority Order 1. ubuntu 2. Windows Boot Manager 3. USB FDD 4. USB HDD 5. ATA HDD0 HITACHI [random string]

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  • webDAV and nautilus returns proxy hostname () error... what am I doing wrong?

    - by Josh Firth
    I am trying to connect to this address https://staff-files.com.auckland.ac.nz/hcwebdav/ for work, which works fine through firefox after it prompts for User/password. I want to access this through nautilus but keep getting: "HTTP ERROR: Cannot resolve proxy hostname () Please select another viewer and try again." I have tried using http, https, dav, davs in the go=location menu, and the same in connect to server method in nautilus as well, which returns the same error. University IT haven't been able to help: can someone here? Thanks, Josh

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  • Moonlight extension not working with Firefox 7

    - by igi
    The web browser I use is Firefox (currently in version 7 in Oneiric). According the Compatibility Check information the Moonlight extension is not compatible with FF7. And, actually, I cannot watch Silverlight streams in an acceptable way:the video gets stuck, the HD keeps buffering (I guess), so I have to close the window. Does anybody know if there is a way to fix this or a suitable alternative?

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  • A Taxonomy of Numerical Methods v1

    - by JoshReuben
    Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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  • SharePoint 2010 Hosting :: Error – HTTP Error 401.1 when Accessing Your SharePoint 2010 Site

    - by mbridge
    When attempting to view a MOSS (SharePoint) 2007 or SharePoint 2010 site locally from a Web Front End (WFE) you get an error stating: “HTTP Error 401.1 – Unauthorized: Access is denied due to invalid credentials.” I have noticed that this happens on Windows 2003/2008 Server SP1/SP2/R2 when using Host Headers and Alternate Access Mappings on a web application in MOSS 2007. If you can access the site from remote machines and cannot access the site from the server itself, then this might be your issue. For all my newer farm installs this includes SharePoint 2007 (MOSS) and SharePoint 2010. I use method number 2 on all SharePoint and SQL Servers in the farm. If you cannot access the web site locally or remotely from other machines then there is an issue with security on the site and/or possibly a Kerberos related security issue I implemented fix #2 listed in the following Microsoft KB Article. I implemented this fix on all servers in the MOSS 2007 Farm (WFE’s and Indexing/Search Server). If using method 1, you would add all Host Headers and Alternate Access Mappings for all web applications to the BackConnectionHostNames value, then you will be able to access the sites locally from the WFE’s. Microsoft KB Link: http://support.microsoft.com/kb/896861 Method 1: Specify Host Names Please follow this steps: 1. Click Start, click Run, type regedit, and then click OK. 2. In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0 3. Right-click MSV1_0, point to New, and then click Multi-String Value. 4. Type BackConnectionHostNames, and then press ENTER. 5. Right-click BackConnectionHostNames, and then click Modify. 6. In the Value data box, type the host name or the host names for the sites that are on the local computer, and then click OK. 7. Quit Registry Editor, and then restart the IISAdmin service. Method 2: Disable the Loopback Check  Please follow this steps: 1. Click Start, click Run, type regedit, and then click OK 2. In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa 3. Right-click Lsa, point to New, and then click DWORD Value. 4. Type DisableLoopbackCheck, and then press ENTER. 5. Right-click DisableLoopbackCheck, and then click Modify. 6. In the Value data box, type 1, and then click OK. 7. Quit Registry Editor, and then restart your computer. Give it try and good luck.

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  • How to throttle email server wide on a shared server?

    - by fdsa
    I have multiple programs that send email on a shared server with a relatively low email limit. These programs are completely separate and can each individually throttle mail but cannot do so in relation to the others. Currently, whenever the hourly limit is reached, our host just starts dropping the emails. They say they have no way to change this behavior and basically suggested that I ask around. Does anyone know of any programs that will throttle email server wide on a shared server?

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  • Convert a DVD Movie Directly to AVI with FairUse Wizard 2.9

    - by DigitalGeekery
    Are you looking for a way to backup your DVD movie collection to AVI?  Today we’ll show you how to rip a DVD movie directly to AVI with FairUse Wizard. About FairUse Wizard FairUse Wizard 2.9 uses the DivX, Xvid, or h.264 codec to convert DVD to an AVI file. It comes in both a free version and commercial version. The free, or “Light” version, can create files up 700MB while the commercial version can output a 1400MB file. This will allow you to back up your movies to CD, or even multiple movies on a single DVD. FairUse Wizard states that it does not work on copy protected discs, but we’ve seen it work on all but some of the most recent copy protection. For this tutorial we’re using the free Light Edition to convert a DVD to AVI. They also offer a commercial version that you can get for $29.99 and it offers even more encoding possibilities for converting video to you portable digital devices. Installation and Configuration Download and install FairUse Wizard. (Download link below). Once the install is complete, open FairUse Wizard by going to Start > All Programs >  FairUse Wizard 2 >  FairUse Wizard 2.   FairUse Wizard will open on the new project screen. Select “Create a new project” and type a project name into the text box. This will be used as the file output name.  Ex: A project name of Simpsons Movie will give you an output file of Simpsons Movie.avi.   Next, browse for a destination folder for the output file and temp files. Note that you will need a minimum of 6 GB of free disk space for the conversion process. Note: Much of that 6 GB will be used for temporary files that we will delete after the conversion process.   Click on the Options button at the bottom.   Under Preferences, choose your preferred video codec and file output size. XviD and x264 are installed by default. If you prefer to use DivX, you will have to install it separately. Also note the “Two pass” option. Checking the “Two pass” box will encode your video twice for higher quality, but will take more time. Un-checking the box will speed up the conversion process.   Under Audio track, note that English subtitles are enabled by default, so to remove the subtitles, you will need to change the dropdown list so it shows only a dash (-). You can also select “Use TV Mode” if your primary playback will be on a 4:3 TV screen. Click “Next.” Full Auto Mode vs. Manual Mode You should now be back to the initial screen. Next, we’ll need to determine whether or not we can use “Full Auto Mode” to convert the movie. The difference is that “Full Auto Mode” will automatically perform a few steps that you will otherwise have to do manually. If you choose the “Full Auto Mode” option, FairUse Wizard will look for the video on the DVD with the longest duration and assume it is the chain that it should convert to AVI. It’s possible, however, your disc may contain a few chains of similar size, such as a theatrical cut and director’s cut, and the longest chain may not be the one you wish to convert. Make sure that “Full auto mode” is not checked yet, and click “Next.”   FairUse Wizard will parse the IFO files and display all video chains longer than 60  seconds. In most cases, you will only find that the largest chain is the one closely matching the duration of the movie. In these instances, you can use “Full Auto Mode.” If you find more than one chain that are close in duration to the length of the movie, consult the literature on the DVD case, or search online, to find the actual running time of the movie. If the proper file chain is not the longest chain, you won’t be able to use “Full Auto Mode.”   Full Auto Mode To use “Full Auto Mode,” simply click the “Back” button to return to the initial screen Now, place a check in the “Full auto mode” check box. Click “Next.” You will then be prompted to chose your DVD drive, then click “OK.” FairUse Wizard will parse the IFO files… … and then prompt you to Select your drive that contains the DVD one more time before beginning the conversion process. Click “OK.”   Manual Mode If you cannot (or don’t wish to) use Full Auto Mode, choose the appropriate video chain and click “Next.” FairUse Wizard will first go through the process of indexing the video. Note: If you get a runtime error during this portion of the process, it likely means that FairUse Wizard cannot handle the copy protection, and thus cannot convert the DVD. FairUse Wizard will automatically detect a cropping region. If necessary, you can edit the cropping region by adjusting the cropping region settings to the left. Click “Next.” Next, click “Auto Detect” to choose the proper field combination. Click “OK” on the pop up window that displays your Field Mode. Then click “Next.” This next screen is mainly comprised of settings from the Options screen. You can make changes at this point such as codec or output size. Click “Next” when ready.   Video Conversion Now the video conversion process will begin. This may take a few hours depending on your system’s hardware. Note: There is a check box to “Shutdown computer when done” if you choose to run the conversion overnight or before leaving for work. The first phase will be video encoding… Then the audio… If you chose the “Two Pass” option, your video video will be encoded again on 2nd pass. Then you’re finished. Unfortunately, FairUse Wizard doesn’t clean up after itself very well. After the process is complete, you’ll want to browse to your output directory and delete all the temporary files as they take up a considerable amount of hard drive space. Now you’re ready to enjoy your movie. Conclusion FairUse Wizard is a nice way to backup your DVD movies to good quality .avi files. You can store them on your hard drive, watch them on a media PC, or burn them to disc. Many DVD players even allow for playback of DivX or XviD encoded video from a CD or DVD. For those of you with children, you can burn that AVI file to CD for your kids, and keep your original DVDs stored safely out of harms way. Download Download FairUse Wizard 2.9 LE Similar Articles Productive Geek Tips Kantaris is a Unique Media Player Based on VLCHow to Make/Edit a movie with Windows Movie Maker in Windows VistaAutomatically Mount and View ISO files in Windows 7 Media CenterTune Your ClearType Font Settings in Windows VistaAdd Images and Metadata to Windows 7 Media Center Movie Library TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Make your Joomla & Drupal Sites Mobile with OSMOBI Integrate Twitter and Delicious and Make Life Easier Design Your Web Pages Using the Golden Ratio Worldwide Growth of the Internet How to Find Your Mac Address Use My TextTools to Edit and Organize Text

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  • Moonlight extension not working with Firefox 8

    - by igi
    The web browser I use is Firefox (currently in version 8 in Oneiric). According the Compatibility Check information the Moonlight extension is not compatible with FF8. And, actually, I cannot watch Silverlight streams in an acceptable way: the video gets stuck, the HD keeps buffering (I guess), so I have to close the window. Does anybody know if there is a way to fix this or a suitable alternative?

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  • Looking ahead at 2011-with Gartner

    - by andrea.mulder
    Speaking of forecasting the future. Gartner highlighted the top 10 technologies and trends that will be strategic for most organizations in 2011. While Gartner's predictions are not specific to CRM, you just cannot help but notice some of the common themes in store for 2011. The top 10 strategic technologies for 2011 include: Cloud Computing Mobile Applications and Media Tablets Social Communications and Collaborations Video Next Generation Analytics Social Analytics Context-Aware Computing Storage Class Memory Ubiquitous Computing Fabric-Based Infrastructure and Computers

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  • Resolving IIS7 HTTP Error 500.19 - Internal Server Error

    - by fatherjack
    LiveJournal Tags: RedGate Tools,SQL Server,Tips and Tricks How To The requested page cannot be accessed because the related configuration data for the page is invalid. As part of my work recently I was moving SQL Monitor from the bespoke XSP web server to be hosted on IIS instead. This didn't go smoothly. I was lucky to be helped by Red Gate's support team (http://twitter.com/kickasssupport). I had SQL Monitor installed and working fine on the XSP site but wanted to move to IIS so I reinstalled the software and chose the IIS option. This wasn't possible as IIS wasn't installed on the server. I went to Control Panel, Windows features and installed IIS and then returned to the SQL Monitor installer. Everything went as planned but when I browsed the site I got a huge error with the message "HTTP Error 500.19 - Internal Server Error The requested page cannot be accessed because the related configuration data for the page is invalid." All links that I could find suggested it was a permissions issue, based on the directory where the config file was stored. I changed this any number of times and also tried the altering its location. Nothing resolved the error. It was only when I was trying the installation again that I read through the details from Red Gate and noted that they referred to ASP settings that I didn't have. Essentially I was seeing this. I had installed IIS using the default settings and that DOESN'T include ASP. When this dawned on me I went back through the windows components installation process and ticked the ASP service within the IIS role. Completing this and going back to the IIS management console I saw something like this; so many more options! When I clicked on the Authentication icon this time I got the option to not only enable Anonymous Authentication but also ASP.NET Impersonation (which is disabled by default). Once I had enabled this the SQL Monitor website worked without error. I think the HTTP Error 500.19 is misleading in this case and at the very least should be able to recognise if the ASP service is installed or not and then to include a hint that it should be. I hope this helps some people and avoids wasting as much of your time as it did mine. Let me know if it helps you.

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  • Send email from postfix server to outside email client

    - by Russ
    I have set up an email server and can send/receive email localhost and I can receive mail from outside sources but I cannot send emails to outside sources. I get this error when I try to send to an outside source such as live.com or gmail.com: Nov 8 22:15:13 server2 postfix/smtp[7598]: 699D480A64: to=, relay=none, delay=122043, delays=122022/0.01/20/0, dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for name=live.com type=MX: Host not found, try again) Any ideas where I could look to resolve this?

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  • What Every Developer Should Know About MSI Components

    - by Alois Kraus
    Hopefully nothing. But if you have to do more than simple XCopy deployment and you need to support updates, upgrades and perhaps side by side scenarios there is no way around MSI. You can create Msi files with a Visual Studio Setup project which is severely limited or you can use the Windows Installer Toolset. I cannot talk about WIX with my German colleagues because WIX has a very special meaning. It is funny to always use the long name when I talk about deployment possibilities. Alternatively you can buy commercial tools which help you to author Msi files but I am not sure how good they are. Given enough pain with existing solutions you can also learn the MSI Apis and create your own packaging solution. If I were you I would use either a commercial visual tool when you do easy deployments or use the free Windows Installer Toolset. Once you know the WIX schema you can create well formed wix xml files easily with any editor. Then you can “compile” from the wxs files your Msi package. Recently I had the “pleasure” to get my hands dirty with C++ (again) and the MSI technology. Installation is a complex topic but after several month of digging into arcane MSI issues I can safely say that there should exist an easier way to install and update files as today. I am not alone with this statement as John Robbins (creator of the cool tool Paraffin) states: “.. It's a brittle and scary API in Windows …”. To help other people struggling with installation issues I present you the advice I (and others) found useful and what will happen if you ignore this advice. What is a MSI file? A MSI file is basically a database with tables which reference each other to control how your un/installation should work. The basic idea is that you declare via these tables what you want to install and MSI controls the how to get your stuff onto or off your machine. Your “stuff” consists usually of files, registry keys, shortcuts and environment variables. Therefore the most important tables are File, Registry, Environment and Shortcut table which define what will be un/installed. The key to master MSI is that every resource (file, registry key ,…) is associated with a MSI component. The actual payload consists of compressed files in the CAB format which can either be embedded into the MSI file or reside beside the MSI file or in a subdirectory below it. To examine MSI files you need Orca a free MSI editor provided by MS. There is also another free editor called Super Orca which does support diffs between MSI and it does not lock the MSI files. But since Orca comes with a shell extension I tend to use only Orca because it is so easy to right click on a MSI file and open it with this tool. How Do I Install It? Double click it. This does work for fresh installations as well as major upgrades. Updates need to be installed via the command line via msiexec /i <msi> REINSTALL=ALL REINSTALLMODE=vomus   This tells the installer to reinstall all already installed features (new features will NOT be installed). The reinstallmode letters do force an overwrite of the old cached package in the %WINDIR%\Installer folder. All files, shortcuts and registry keys are redeployed if they are missing or need to be replaced with a newer version. When things did go really wrong and you want to overwrite everything unconditionally use REINSTALLMODE=vamus. How To Enable MSI Logs? You can download a MSI from Microsoft which installs some registry keys to enable full MSI logging. The log files can be found in your %TEMP% folder and are called MSIxxxx.log. Alternatively you can add to your msiexec command line the option msiexec …. /l*vx <LogFileName> Personally I find it rather strange that * does not mean full logging. To really get all logs I need to add v and x which is documented in the msiexec help but I still find this behavior unintuitive. What are MSI components? The whole MSI logic is bound to the concept of MSI components. Nearly every msi table has a Component column which binds an installable resource to a component. Below are the screenshots of the FeatureComponents and Component table of an example MSI. The Feature table defines basically the feature hierarchy.  To find out what belongs to a feature you need to look at the FeatureComponents table where for each feature the components are listed which will be installed when a feature is installed. The MSI components are defined in the  Component table. This table has as first column the component name and as second column the component id which is a GUID. All resources you want to install belong to a MSI component. Therefore nearly all MSI tables have a Component_ column which contains the component name. If you look e.g. a the File table you see that every file belongs to a component which is true for all other tables which install resources. The component table is the glue between all other tables which contain the resources you want to install. So far so easy. Why is MSI then so complex? Most MSI problems arise from the fact that you did violate a MSI component rule in one or the other way. When you install a feature the reference count for all components belonging to this feature will increase by one. If your component is installed by more than one feature it will get a higher refcount. When you uninstall a feature its refcount will drop by one. Interesting things happen if the component reference count reaches zero: Then all associated resources will be deleted. That looks like a reasonable thing and it is. What it makes complex are the strange component rules you have to follow. Below are some important component rules from the Tao of the Windows Installer … Rule 16: Follow Component Rules Components are a very important part of the Installer technology. They are the means whereby the Installer manages the resources that make up your application. The SDK provides the following guidelines for creating components in your package: Never create two components that install a resource under the same name and target location. If a resource must be duplicated in multiple components, change its name or target location in each component. This rule should be applied across applications, products, product versions, and companies. Two components must not have the same key path file. This is a consequence of the previous rule. The key path value points to a particular file or folder belonging to the component that the installer uses to detect the component. If two components had the same key path file, the installer would be unable to distinguish which component is installed. Two components however may share a key path folder. Do not create a version of a component that is incompatible with all previous versions of the component. This rule should be applied across applications, products, product versions, and companies. Do not create components containing resources that will need to be installed into more than one directory on the user’s system. The installer installs all of the resources in a component into the same directory. It is not possible to install some resources into subdirectories. Do not include more than one COM server per component. If a component contains a COM server, this must be the key path for the component. Do not specify more than one file per component as a target for the Start menu or a Desktop shortcut. … And these rules do not even talk about component ids, update packages and upgrades which you need to understand as well. Lets suppose you install two MSIs (MSI1 and MSI2) which have the same ComponentId but different component names. Both do install the same file. What will happen when you uninstall MSI2?   Hm the file should stay there. But the component names are different. Yes and yes. But MSI uses not use the component name as key for the refcount. Instead the ComponentId column of the Component table which contains a GUID is used as identifier under which the refcount is stored. The components Comp1 and Comp2 are identical from the MSI perspective. After the installation of both MSIs the Component with the Id {100000….} has a refcount of two. After uninstallation of one MSI there is still a refcount of one which drops to zero just as expected when we uninstall the last msi. Then the file which was the same for both MSIs is deleted. You should remember that MSI keeps a refcount across MSIs for components with the same component id. MSI does manage components not the resources you did install. The resources associated with a component are then and only then deleted when the refcount of the component reaches zero.   The dependencies between features, components and resources can be described as relations. m,k are numbers >= 1, n can be 0. Inside a MSI the following relations are valid Feature    1  –> n Components Component    1 –> m Features Component      1  –>  k Resources These relations express that one feature can install several components and features can share components between them. Every (meaningful) component will install at least one resource which means that its name (primary key to stay in database speak) does occur in some other table in the Component column as value which installs some resource. Lets make it clear with an example. We want to install with the feature MainFeature some files a registry key and a shortcut. We can then create components Comp1..3 which are referenced by the resources defined in the corresponding tables.   Feature Component Registry File Shortcuts MainFeature Comp1 RegistryKey1     MainFeature Comp2   File.txt   MainFeature Comp3   File2.txt Shortcut to File2.txt   It is illegal that the same resource is part of more than one component since this would break the refcount mechanism. Lets illustrate this:            Feature ComponentId Resource Reference Count Feature1 {1000-…} File1.txt 1 Feature2 {2000-….} File1.txt 1 The installation part works well but what happens when you uninstall Feature2? Component {20000…} gets a refcount of zero where MSI deletes all resources belonging to this component. In this case File1.txt will be deleted. But Feature1 still has another component {10000…} with a refcount of one which means that the file was deleted too early. You just have ruined your installation. To fix it you then need to click on the Repair button under Add/Remove Programs to let MSI reinstall any missing registry keys, files or shortcuts. The vigilant reader might has noticed that there is more in the Component table. Beside its name and GUID it has also an installation directory, attributes and a KeyPath. The KeyPath is a reference to a file or registry key which is used to detect if the component is already installed. This becomes important when you repair or uninstall a component. To find out if the component is already installed MSI checks if the registry key or file referenced by the KeyPath property does exist. When it does not exist it assumes that it was either already uninstalled (can lead to problems during uninstall) or that it is already installed and all is fine. Why is this detail so important? Lets put all files into one component. The KeyPath should be then one of the files of your component to check if it was installed or not. When your installation becomes corrupt because a file was deleted you cannot repair it with the Repair button under Add/Remove Programs because MSI checks the component integrity via the Resource referenced by its KeyPath. As long as you did not delete the KeyPath file MSI thinks all resources with your component are installed and never executes any repair action. You get even more trouble when you try to remove files during an upgrade (you cannot remove files during an update) from your super component which contains all files. The only way out and therefore best practice is to assign for every resource you want to install an extra component. This ensures painless updatability and repairs and you have much less effort to remove specific files during an upgrade. In effect you get this best practice relation Feature 1  –> n Components Component   1  –>  1 Resources MSI Component Rules Rule 1 – One component per resource Every resource you want to install (file, registry key, value, environment value, shortcut, directory, …) must get its own component which does never change between versions as long as the install location is the same. Penalty If you add more than one resources to a component you will break the repair capability of MSI because the KeyPath is used to check if the component needs repair. MSI ComponentId Files MSI 1.0 {1000} File1-5 MSI 2.0 {2000} File2-5 You want to remove File1 in version 2.0 of your MSI. Since you want to keep the other files you create a new component and add them there. MSI will delete all files if the component refcount of {1000} drops to zero. The files you want to keep are added to the new component {2000}. Ok that does work if your upgrade does uninstall the old MSI first. This will cause the refcount of all previously installed components to reach zero which means that all files present in version 1.0 are deleted. But there is a faster way to perform your upgrade by first installing your new MSI and then remove the old one.  If you choose this upgrade path then you will loose File1-5 after your upgrade and not only File1 as intended by your new component design.   Rule 2 – Only add, never remove resources from a component If you did follow rule 1 you will not need Rule 2. You can add in a patch more resources to one component. That is ok. But you can never remove anything from it. There are tricky ways around that but I do not want to encourage bad component design. Penalty Lets assume you have 2 MSI files which install under the same component one file   MSI1 MSI2 {1000} - ComponentId {1000} – ComponentId File1.txt File2.txt   When you install and uninstall both MSIs you will end up with an installation where either File1 or File2 will be left. Why? It seems that MSI does not store the resources associated with each component in its internal database. Instead Windows will simply query the MSI that is currently uninstalled for all resources belonging to this component. Since it will find only one file and not two it will only uninstall one file. That is the main reason why you never can remove resources from a component!   Rule 3 Never Remove A Component From an Update MSI. This is the same as if you change the GUID of a component by accident for your new update package. The resulting update package will not contain all components from the previously installed package. Penalty When you remove a component from a feature MSI will set the feature state during update to Advertised and log a warning message into its log file when you did enable MSI logging. SELMGR: ComponentId '{2DCEA1BA-3E27-E222-484C-D0D66AEA4F62}' is registered to feature 'xxxxxxx, but is not present in the Component table.  Removal of components from a feature is not supported! MSI (c) (24:44) [07:53:13:436]: SELMGR: Removal of a component from a feature is not supported Advertised means that MSI treats all components of this feature as not installed. As a consequence during uninstall nothing will be removed since it is not installed! This is not only bad because uninstall does no longer work but this feature will also not get the required patches. All other features which have followed component versioning rules for update packages will be updated but the one faulty feature will not. This results in very hard to find bugs why an update was only partially successful. Things got better with Windows Installer 4.5 but you cannot rely on that nobody will use an older installer. It is a good idea to add to your update msiexec call MSIENFORCEUPGRADECOMPONENTRULES=1 which will abort the installation if you did violate this rule.

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  • How to find and fix performance problems in ORM powered applications

    - by FransBouma
    Once in a while we get requests about how to fix performance problems with our framework. As it comes down to following the same steps and looking into the same things every single time, I decided to write a blogpost about it instead, so more people can learn from this and solve performance problems in their O/R mapper powered applications. In some parts it's focused on LLBLGen Pro but it's also usable for other O/R mapping frameworks, as the vast majority of performance problems in O/R mapper powered applications are not specific for a certain O/R mapper framework. Too often, the developer looks at the wrong part of the application, trying to fix what isn't a problem in that part, and getting frustrated that 'things are so slow with <insert your favorite framework X here>'. I'm in the O/R mapper business for a long time now (almost 10 years, full time) and as it's a small world, we O/R mapper developers know almost all tricks to pull off by now: we all know what to do to make task ABC faster and what compromises (because there are almost always compromises) to deal with if we decide to make ABC faster that way. Some O/R mapper frameworks are faster in X, others in Y, but you can be sure the difference is mainly a result of a compromise some developers are willing to deal with and others aren't. That's why the O/R mapper frameworks on the market today are different in many ways, even though they all fetch and save entities from and to a database. I'm not suggesting there's no room for improvement in today's O/R mapper frameworks, there always is, but it's not a matter of 'the slowness of the application is caused by the O/R mapper' anymore. Perhaps query generation can be optimized a bit here, row materialization can be optimized a bit there, but it's mainly coming down to milliseconds. Still worth it if you're a framework developer, but it's not much compared to the time spend inside databases and in user code: if a complete fetch takes 40ms or 50ms (from call to entity object collection), it won't make a difference for your application as that 10ms difference won't be noticed. That's why it's very important to find the real locations of the problems so developers can fix them properly and don't get frustrated because their quest to get a fast, performing application failed. Performance tuning basics and rules Finding and fixing performance problems in any application is a strict procedure with four prescribed steps: isolate, analyze, interpret and fix, in that order. It's key that you don't skip a step nor make assumptions: these steps help you find the reason of a problem which seems to be there, and how to fix it or leave it as-is. Skipping a step, or when you assume things will be bad/slow without doing analysis will lead to the path of premature optimization and won't actually solve your problems, only create new ones. The most important rule of finding and fixing performance problems in software is that you have to understand what 'performance problem' actually means. Most developers will say "when a piece of software / code is slow, you have a performance problem". But is that actually the case? If I write a Linq query which will aggregate, group and sort 5 million rows from several tables to produce a resultset of 10 rows, it might take more than a couple of milliseconds before that resultset is ready to be consumed by other logic. If I solely look at the Linq query, the code consuming the resultset of the 10 rows and then look at the time it takes to complete the whole procedure, it will appear to me to be slow: all that time taken to produce and consume 10 rows? But if you look closer, if you analyze and interpret the situation, you'll see it does a tremendous amount of work, and in that light it might even be extremely fast. With every performance problem you encounter, always do realize that what you're trying to solve is perhaps not a technical problem at all, but a perception problem. The second most important rule you have to understand is based on the old saying "Penny wise, Pound Foolish": the part which takes e.g. 5% of the total time T for a given task isn't worth optimizing if you have another part which takes a much larger part of the total time T for that same given task. Optimizing parts which are relatively insignificant for the total time taken is not going to bring you better results overall, even if you totally optimize that part away. This is the core reason why analysis of the complete set of application parts which participate in a given task is key to being successful in solving performance problems: No analysis -> no problem -> no solution. One warning up front: hunting for performance will always include making compromises. Fast software can be made maintainable, but if you want to squeeze as much performance out of your software, you will inevitably be faced with the dilemma of compromising one or more from the group {readability, maintainability, features} for the extra performance you think you'll gain. It's then up to you to decide whether it's worth it. In almost all cases it's not. The reason for this is simple: the vast majority of performance problems can be solved by implementing the proper algorithms, the ones with proven Big O-characteristics so you know the performance you'll get plus you know the algorithm will work. The time taken by the algorithm implementing code is inevitable: you already implemented the best algorithm. You might find some optimizations on the technical level but in general these are minor. Let's look at the four steps to see how they guide us through the quest to find and fix performance problems. Isolate The first thing you need to do is to isolate the areas in your application which are assumed to be slow. For example, if your application is a web application and a given page is taking several seconds or even minutes to load, it's a good candidate to check out. It's important to start with the isolate step because it allows you to focus on a single code path per area with a clear begin and end and ignore the rest. The rest of the steps are taken per identified problematic area. Keep in mind that isolation focuses on tasks in an application, not code snippets. A task is something that's started in your application by either another task or the user, or another program, and has a beginning and an end. You can see a task as a piece of functionality offered by your application.  Analyze Once you've determined the problem areas, you have to perform analysis on the code paths of each area, to see where the performance problems occur and which areas are not the problem. This is a multi-layered effort: an application which uses an O/R mapper typically consists of multiple parts: there's likely some kind of interface (web, webservice, windows etc.), a part which controls the interface and business logic, the O/R mapper part and the RDBMS, all connected with either a network or inter-process connections provided by the OS or other means. Each of these parts, including the connectivity plumbing, eat up a part of the total time it takes to complete a task, e.g. load a webpage with all orders of a given customer X. To understand which parts participate in the task / area we're investigating and how much they contribute to the total time taken to complete the task, analysis of each participating task is essential. Start with the code you wrote which starts the task, analyze the code and track the path it follows through your application. What does the code do along the way, verify whether it's correct or not. Analyze whether you have implemented the right algorithms in your code for this particular area. Remember we're looking at one area at a time, which means we're ignoring all other code paths, just the code path of the current problematic area, from begin to end and back. Don't dig in and start optimizing at the code level just yet. We're just analyzing. If your analysis reveals big architectural stupidity, it's perhaps a good idea to rethink the architecture at this point. For the rest, we're analyzing which means we collect data about what could be wrong, for each participating part of the complete application. Reviewing the code you wrote is a good tool to get deeper understanding of what is going on for a given task but ultimately it lacks precision and overview what really happens: humans aren't good code interpreters, computers are. We therefore need to utilize tools to get deeper understanding about which parts contribute how much time to the total task, triggered by which other parts and for example how many times are they called. There are two different kind of tools which are necessary: .NET profilers and O/R mapper / RDBMS profilers. .NET profiling .NET profilers (e.g. dotTrace by JetBrains or Ants by Red Gate software) show exactly which pieces of code are called, how many times they're called, and the time it took to run that piece of code, at the method level and sometimes even at the line level. The .NET profilers are essential tools for understanding whether the time taken to complete a given task / area in your application is consumed by .NET code, where exactly in your code, the path to that code, how many times that code was called by other code and thus reveals where hotspots are located: the areas where a solution can be found. Importantly, they also reveal which areas can be left alone: remember our penny wise pound foolish saying: if a profiler reveals that a group of methods are fast, or don't contribute much to the total time taken for a given task, ignore them. Even if the code in them is perhaps complex and looks like a candidate for optimization: you can work all day on that, it won't matter.  As we're focusing on a single area of the application, it's best to start profiling right before you actually activate the task/area. Most .NET profilers support this by starting the application without starting the profiling procedure just yet. You navigate to the particular part which is slow, start profiling in the profiler, in your application you perform the actions which are considered slow, and afterwards you get a snapshot in the profiler. The snapshot contains the data collected by the profiler during the slow action, so most data is produced by code in the area to investigate. This is important, because it allows you to stay focused on a single area. O/R mapper and RDBMS profiling .NET profilers give you a good insight in the .NET side of things, but not in the RDBMS side of the application. As this article is about O/R mapper powered applications, we're also looking at databases, and the software making it possible to consume the database in your application: the O/R mapper. To understand which parts of the O/R mapper and database participate how much to the total time taken for task T, we need different tools. There are two kind of tools focusing on O/R mappers and database performance profiling: O/R mapper profilers and RDBMS profilers. For O/R mapper profilers, you can look at LLBLGen Prof by hibernating rhinos or the Linq to Sql/LLBLGen Pro profiler by Huagati. Hibernating rhinos also have profilers for other O/R mappers like NHibernate (NHProf) and Entity Framework (EFProf) and work the same as LLBLGen Prof. For RDBMS profilers, you have to look whether the RDBMS vendor has a profiler. For example for SQL Server, the profiler is shipped with SQL Server, for Oracle it's build into the RDBMS, however there are also 3rd party tools. Which tool you're using isn't really important, what's important is that you get insight in which queries are executed during the task / area we're currently focused on and how long they took. Here, the O/R mapper profilers have an advantage as they collect the time it took to execute the query from the application's perspective so they also collect the time it took to transport data across the network. This is important because a query which returns a massive resultset or a resultset with large blob/clob/ntext/image fields takes more time to get transported across the network than a small resultset and a database profiler doesn't take this into account most of the time. Another tool to use in this case, which is more low level and not all O/R mappers support it (though LLBLGen Pro and NHibernate as well do) is tracing: most O/R mappers offer some form of tracing or logging system which you can use to collect the SQL generated and executed and often also other activity behind the scenes. While tracing can produce a tremendous amount of data in some cases, it also gives insight in what's going on. Interpret After we've completed the analysis step it's time to look at the data we've collected. We've done code reviews to see whether we've done anything stupid and which parts actually take place and if the proper algorithms have been implemented. We've done .NET profiling to see which parts are choke points and how much time they contribute to the total time taken to complete the task we're investigating. We've performed O/R mapper profiling and RDBMS profiling to see which queries were executed during the task, how many queries were generated and executed and how long they took to complete, including network transportation. All this data reveals two things: which parts are big contributors to the total time taken and which parts are irrelevant. Both aspects are very important. The parts which are irrelevant (i.e. don't contribute significantly to the total time taken) can be ignored from now on, we won't look at them. The parts which contribute a lot to the total time taken are important to look at. We now have to first look at the .NET profiler results, to see whether the time taken is consumed in our own code, in .NET framework code, in the O/R mapper itself or somewhere else. For example if most of the time is consumed by DbCommand.ExecuteReader, the time it took to complete the task is depending on the time the data is fetched from the database. If there was just 1 query executed, according to tracing or O/R mapper profilers / RDBMS profilers, check whether that query is optimal, uses indexes or has to deal with a lot of data. Interpret means that you follow the path from begin to end through the data collected and determine where, along the path, the most time is contributed. It also means that you have to check whether this was expected or is totally unexpected. My previous example of the 10 row resultset of a query which groups millions of rows will likely reveal that a long time is spend inside the database and almost no time is spend in the .NET code, meaning the RDBMS part contributes the most to the total time taken, the rest is compared to that time, irrelevant. Considering the vastness of the source data set, it's expected this will take some time. However, does it need tweaking? Perhaps all possible tweaks are already in place. In the interpret step you then have to decide that further action in this area is necessary or not, based on what the analysis results show: if the analysis results were unexpected and in the area where the most time is contributed to the total time taken is room for improvement, action should be taken. If not, you can only accept the situation and move on. In all cases, document your decision together with the analysis you've done. If you decide that the perceived performance problem is actually expected due to the nature of the task performed, it's essential that in the future when someone else looks at the application and starts asking questions you can answer them properly and new analysis is only necessary if situations changed. Fix After interpreting the analysis results you've concluded that some areas need adjustment. This is the fix step: you're actively correcting the performance problem with proper action targeted at the real cause. In many cases related to O/R mapper powered applications it means you'll use different features of the O/R mapper to achieve the same goal, or apply optimizations at the RDBMS level. It could also mean you apply caching inside your application (compromise memory consumption over performance) to avoid unnecessary re-querying data and re-consuming the results. After applying a change, it's key you re-do the analysis and interpretation steps: compare the results and expectations with what you had before, to see whether your actions had any effect or whether it moved the problem to a different part of the application. Don't fall into the trap to do partly analysis: do the full analysis again: .NET profiling and O/R mapper / RDBMS profiling. It might very well be that the changes you've made make one part faster but another part significantly slower, in such a way that the overall problem hasn't changed at all. Performance tuning is dealing with compromises and making choices: to use one feature over the other, to accept a higher memory footprint, to go away from the strict-OO path and execute queries directly onto the RDBMS, these are choices and compromises which will cross your path if you want to fix performance problems with respect to O/R mappers or data-access and databases in general. In most cases it's not a big issue: alternatives are often good choices too and the compromises aren't that hard to deal with. What is important is that you document why you made a choice, a compromise: which analysis data, which interpretation led you to the choice made. This is key for good maintainability in the years to come. Most common performance problems with O/R mappers Below is an incomplete list of common performance problems related to data-access / O/R mappers / RDBMS code. It will help you with fixing the hotspots you found in the interpretation step. SELECT N+1: (Lazy-loading specific). Lazy loading triggered performance bottlenecks. Consider a list of Orders bound to a grid. You have a Field mapped onto a related field in Order, Customer.CompanyName. Showing this column in the grid will make the grid fetch (indirectly) for each row the Customer row. This means you'll get for the single list not 1 query (for the orders) but 1+(the number of orders shown) queries. To solve this: use eager loading using a prefetch path to fetch the customers with the orders. SELECT N+1 is easy to spot with an O/R mapper profiler or RDBMS profiler: if you see a lot of identical queries executed at once, you have this problem. Prefetch paths using many path nodes or sorting, or limiting. Eager loading problem. Prefetch paths can help with performance, but as 1 query is fetched per node, it can be the number of data fetched in a child node is bigger than you think. Also consider that data in every node is merged on the client within the parent. This is fast, but it also can take some time if you fetch massive amounts of entities. If you keep fetches small, you can use tuning parameters like the ParameterizedPrefetchPathThreshold setting to get more optimal queries. Deep inheritance hierarchies of type Target Per Entity/Type. If you use inheritance of type Target per Entity / Type (each type in the inheritance hierarchy is mapped onto its own table/view), fetches will join subtype- and supertype tables in many cases, which can lead to a lot of performance problems if the hierarchy has many types. With this problem, keep inheritance to a minimum if possible, or switch to a hierarchy of type Target Per Hierarchy, which means all entities in the inheritance hierarchy are mapped onto the same table/view. Of course this has its own set of drawbacks, but it's a compromise you might want to take. Fetching massive amounts of data by fetching large lists of entities. LLBLGen Pro supports paging (and limiting the # of rows returned), which is often key to process through large sets of data. Use paging on the RDBMS if possible (so a query is executed which returns only the rows in the page requested). When using paging in a web application, be sure that you switch server-side paging on on the datasourcecontrol used. In this case, paging on the grid alone is not enough: this can lead to fetching a lot of data which is then loaded into the grid and paged there. Keep note that analyzing queries for paging could lead to the false assumption that paging doesn't occur, e.g. when the query contains a field of type ntext/image/clob/blob and DISTINCT can't be applied while it should have (e.g. due to a join): the datareader will do DISTINCT filtering on the client. this is a little slower but it does perform paging functionality on the data-reader so it won't fetch all rows even if the query suggests it does. Fetch massive amounts of data because blob/clob/ntext/image fields aren't excluded. LLBLGen Pro supports field exclusion for queries. You can exclude fields (also in prefetch paths) per query to avoid fetching all fields of an entity, e.g. when you don't need them for the logic consuming the resultset. Excluding fields can greatly reduce the amount of time spend on data-transport across the network. Use this optimization if you see that there's a big difference between query execution time on the RDBMS and the time reported by the .NET profiler for the ExecuteReader method call. Doing client-side aggregates/scalar calculations by consuming a lot of data. If possible, try to formulate a scalar query or group by query using the projection system or GetScalar functionality of LLBLGen Pro to do data consumption on the RDBMS server. It's far more efficient to process data on the RDBMS server than to first load it all in memory, then traverse the data in-memory to calculate a value. Using .ToList() constructs inside linq queries. It might be you use .ToList() somewhere in a Linq query which makes the query be run partially in-memory. Example: var q = from c in metaData.Customers.ToList() where c.Country=="Norway" select c; This will actually fetch all customers in-memory and do an in-memory filtering, as the linq query is defined on an IEnumerable<T>, and not on the IQueryable<T>. Linq is nice, but it can often be a bit unclear where some parts of a Linq query might run. Fetching all entities to delete into memory first. To delete a set of entities it's rather inefficient to first fetch them all into memory and then delete them one by one. It's more efficient to execute a DELETE FROM ... WHERE query on the database directly to delete the entities in one go. LLBLGen Pro supports this feature, and so do some other O/R mappers. It's not always possible to do this operation in the context of an O/R mapper however: if an O/R mapper relies on a cache, these kind of operations are likely not supported because they make it impossible to track whether an entity is actually removed from the DB and thus can be removed from the cache. Fetching all entities to update with an expression into memory first. Similar to the previous point: it is more efficient to update a set of entities directly with a single UPDATE query using an expression instead of fetching the entities into memory first and then updating the entities in a loop, and afterwards saving them. It might however be a compromise you don't want to take as it is working around the idea of having an object graph in memory which is manipulated and instead makes the code fully aware there's a RDBMS somewhere. Conclusion Performance tuning is almost always about compromises and making choices. It's also about knowing where to look and how the systems in play behave and should behave. The four steps I provided should help you stay focused on the real problem and lead you towards the solution. Knowing how to optimally use the systems participating in your own code (.NET framework, O/R mapper, RDBMS, network/services) is key for success as well as knowing what's going on inside the application you built. I hope you'll find this guide useful in tracking down performance problems and dealing with them in a useful way.  

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