Search Results

Search found 4503 results on 181 pages for 'logical operator'.

Page 111/181 | < Previous Page | 107 108 109 110 111 112 113 114 115 116 117 118  | Next Page >

• Deleting Unused Swaps Partions

  - by Nikita Kononov

  Good evening everyone , I got a little issue with Swap Partitions. Due to some issues after installing Ubuntu first time, I reinstalled it and now I have 3 Swaps. Here is sudo fdisk -l result Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0xaa9693fe Device Boot Start End Blocks Id System /dev/sda1 2048 52430847 26214400 1c Hidden W95 FAT32 (LBA) /dev/sda2 * 52430848 540677076 244123114+ 7 HPFS/NTFS/exFAT /dev/sda3 540678142 1465147391 462234625 5 Extended Partition 3 does not start on physical sector boundary. /dev/sda5 1452750848 1465147391 6198272 82 Linux swap / Solaris /dev/sda6 1440352256 1452742655 6195200 82 Linux swap / Solaris /dev/sda7 540678144 1427951615 443636736 83 Linux /dev/sda8 1427953664 1440339967 6193152 82 Linux swap / Solaris So Swaps in /dev/sda5 and /dev/sda6 are no longer in use as far as I understand and thus I was planning to delete them, however faced a problem. What I did is download and burn Gparted Live CD and boot it up, tried to delete those partitions but I have no idea how to add 12GB unallocated memory to the existing OS partition in this case to /dev/sda7 Is there anyway I can delete 2 swaps and extend unallocated memory to /dev/sda7 partion? Thank you in advance!

  Read the article

• How to run multiple distros using lvm

  - by Mark

  I've seen quite a few posts around about running multiple distros but not sure they apply to using LVM (and without Windows). I'm using a machine that's about 3 years old. Setup: Intel Core i7 2.8GHz 8GB Ram 1TB SATA HDD At this point, I'd like to install 12.10 and Mint 14, leaving the option open to install additional distros down the road. I could be way off, but I'm thinking about creating at least 2 primary /boot partitions (1 for 12.10 and 1 for Mint) and another partition for LVM leaving room for additional /boot partitions. Then creating a VG and separate LVs for Ubuntu 12.10 and Linux Mint 14. I understand I can share partitions between the 2 installs, but I'm only using this for testing and I have tons of space to play with. LVM seemed logical considering I may want to install and test additional distros. I guess I could share the /swap partition across the board without problems, right? I'm unclear about GRUB2. How do I handle the bootloader situation? Install 12.10 and get it running then make changes to grub.cfg after installing Mint? And do I not install GRUB for Mint or do I install it in a different location? Any guidance would be appreciated.

  Read the article

• Grub does not show a Windows 8 option after dual boot

  - by skytreader

  So, I've successfully dual-booted my Windows 8 machine with Ubuntu 12.04 . However, I still don't have a convenient method of choosing what OS to load at boot time. After installing Ubuntu, my computer still loads Windows 8 directly. I then added grubx64.efi to the white list of my boot loader. But after that, my machine loads Ubuntu directly without even a shadow of GRUB showing up! I used boot-repair and I got this paste.ubuntu URL: paste.ubuntu.com/1326074. After running boot-repair (and re-white listing the grubx64.efi file), GRUB now shows up but without any Windows 8 option! Lastly, I ran sudo fdisk -l and it gave me this: WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x6396389f Device Boot Start End Blocks Id System /dev/sda1 1 1465149167 732574583+ ee GPT Partition 1 does not start on physical sector boundary. I'm guessing my problem has something to do with the warning from fdisk above but I don't know what to do with it. How do I proceed now?

  Read the article

• Interview Questions in OOP

  - by Fero

  Hi all, I faced the below interview questions in OOP under PHP language. Kindly clear my clarifications regarding this. I am very confused. As i am a beginner to OOP i got too confused. Could anyone clarify these things clearly? Difference between Abstract class and interface. Interviewer : Let us consider abstract class contains three abstract methods such as a,b,c and interface contains three methods a,b,c. In this case these do the same functionality. Then why are going for abstract and why are we going for interface. Me : ? static keyword. Interviewer: We call static method without creating object by using scope resolution operator in PHP. As well as we can able to call concrete methods also. Then what is need of static keyword there? Me : .... final keyword. Interviewer: Give me any scenario of using final keyword. Me : For db connection related method Interviewer: Other than that? Me: ... Constructor. Interviewer: What is the use of constructor? Me : There is no need for object to access this. It will call automatically when the class calls. Interviewer: Other than that? Me : .... Thanks in advance...

  Read the article

• Why can't I compare two Texture2D's?

  - by Fiona

  I am trying to use an accessor, as it seems to me that that is the only way to accomplish what I want to do. Here is my code: Game1.cs public class GroundTexture { private Texture2D dirt; public Texture2D Dirt { get { return dirt; } set { dirt = value; } } } public class Main : Game { public static Texture2D texture = tile.Texture; GroundTexture groundTexture = new GroundTexture(); public static Texture2D dirt; protected override void LoadContent() { Tile tile = (Tile)currentLevel.GetTile(20, 20); dirt = Content.Load<Texture2D>("Dirt"); groundTexture.Dirt = dirt; Texture2D texture = tile.Texture; } protected override void Update(GameTime gameTime) { if (texture == groundTexture.Dirt) { player.TileCollision(groundBounds); } base.Update(gameTime); } } I removed irrelevant information from the LoadContent and Update functions. On the following line: if (texture == groundTexture.Dirt) I am getting the error Operator '==' cannot be applied to operands of type 'Microsoft.Xna.Framework.Graphics.Texture2D' and 'Game1.GroundTexture' Am I using the accessor correctly? And why do I get this error? "Dirt" is Texture2D, so they should be comparable. This using a few functions from a program called Realm Factory, which is a tile editor. The numbers "20, 20" are just a sample of the level I made below: tile.Texture returns the sprite, which here is the content item Dirt.png Thank you very much! (I posted this on the main Stackoverflow site, but after several days didn't get a response. Since it has to do mainly with Texture2D, I figured I'd ask here.)

  Read the article

• Working with documents and SharePoint - Best practices

  - by KunaalKapoor

  Follow these simple guidelines to make collaboration using SharePoint easier:1. File Name:While it is allowed to use spaces in your filename (and maybe it seems even logical to do so), don’t use them if your file will end up (or is born on) SharePoint. When you use the “download a copy” functionality, SharePoint will replace the spaces with an “_”. This might (will) result in inconsistency when you upload the “same” file again, since SharePoint will see this as a different file (since the filename is different). I recommend using a filename with Capitalization style naming guideline. For instance: the document “Overall governance model.docx” would be named “OverallGovernanceModel.docx”Use the TITLE field in the office applications to give your document a title (and subtitle and keywords, .) The title column can be used in a view in a library. You can get to the document properties by clicking on 'Office Button/Prepare/Properties'. (Office 2007). This is metadata that is stored with the document, and will remain in the document (even if you exchange this document via e-mail, via an external hard drive). The filename cannot be longer than 128 characters. (and that is IMHO far beyond reasonable) You cannot use any of these characters: ” # % & * : < > ? \ / { | } ~ 2. Versioning:SharePoint has a built-in versioning system. You can work with major (published) versions, and minor (draft) versions. Of each of these two document types, you can store a numbers of versions that are kept. Watch out, each version is saved, not only the delta between 2 versions, and this counts to your Site Collection Quota. (Example: you have a Word document with a size of 2 MB. When you keep 5 Drafts this will result in storing (and consuming) 10 MB.So, don’t call your document “NewUserAccountProcessDRAFTv1.docx”, but “NewUserAccountProcess.docx” and use versioning setting in your library.You can enable views on your library to display the version number.You can enable the version number to be displayed in a Word document.3. Use MetadataUse metadata to assign other properties to documents, so it can be easily identified, sorted- or grouped by.

  Read the article

• Dealing with three Windows partitions in dual boot installation

  - by Tim

  For dual-boot installation of Ubuntu after Windows. Quoted from ubuntuguide If a Windows boot partition exists as a second NTFS partition, it should be left alone. If there is a Windows recovery partition also installed, it can also be left alone as long as there are only two NTFS partitions total on the hard drive (i.e. there is no NTFS boot partition as well). If there are a total of 3 NTFS partitions on the hard drive, then the third Windows NTFS partition (the recovery partition) should be removed after creating Recovery CDs from it (see here). In the last case where Windows has three partitions, I was wondering why it says the recovery partition shall be removed? Is it possible to keep the three and create another extended partition with several logical partitions for installing Ubuntu and dual-booting the two OSes? I plan to dual-boot install Ubuntu 10.04 with existing Windows 7. Following is the layout of the current partitions of my hard drive viewed from Windows 7: So must I remove the Lenovo_Recovery (Q:) partition for the same reason you give for the first question? Thanks and regards!

  Read the article

• Digital HD Transition

  - by Bill Evjen

  The HD Experience Roughly 53% of the viewing public has HD capable devices in their home 24% think they are watching HD while they have no subscription to any HD content Today’s HD Considerations Choices abound: format resolution – 720p, 1080i/p frame rates compression and wrapping audio compression and delivery metadata packaging, delivery, and usage content delivery protocols Metadata is going to be a part of the overall experience With emerging technologies: Super Hi-Vision (SHV, UHDTV 4320p), 3D HEVC/H.265, WEBM/VP8 HDBaseT, P2PTV Dolby Pulse/HE-AAC Industry standardization Metadata registration, packaging, and delivery standards Improved picture and sound quality is a logical next step but we need to also think about the end to end viewing experience including; 3D video and audio content Mixed-mode viewing to bring interactive and immersive experiences Content Transportability both on-to and off-of the aircraft High Definition Standardization Analog switch off around the world DTV transition completed: 17 countries DTV transition in progress: 45 countries The EU has mandated the end of 2012 as the final date for Analog Switch Off D-Cinema was standardized by SMPTE in 2006 Airlines are installing HD displays today Passengers are bringing their own devices now HD TV on airlines are getting bigger and bigger – bigger than SD was – now up to 23” Gray scale data input for color – 6 to 8 bit Contrast – 400 to 700 Backlit – LED Encryption – can it be the same for HD? PPV in the cabin?

  Read the article

• Parsing mathematical experssions with two values that have parenthesis and minus signs

  - by user45921

  I'm trying to parse equations like these which only has two values or the square root of a certain value from a text file: 100+100 -100-100 -(100)+(-100) sqrt(100) by the minues signs, parenthesis and the operator symbol in the middle and the square root, and I have no idea how to start off... I've got the file part done and the simple calculation parts except that I couldnt get my program to solve the equations in the above. #include <stdio.h> #include <string.h> #include <stdlib.h> #include <math.h> main(){ FILE *fp; char buff[255], sym,sym2,del1,del2,del3,del4; double num1, num2; int ret; fp = fopen("input.txt","r"); while(fgets(buff,sizeof(buff),fp)!=NULL){ char *tok = buff; sscanf(tok,"%lf%c%lf",&num1,&sym,&num2); switch(sym){ case '+': printf("%lf\n", num1+num2); break; case '-': printf("%lf\n", num1-num2); break; case '*': printf("%lf\n", num1*num2); break; case '/': printf("%lf\n", num1/num2); break; default: printf("The input value is not correct\n"); break; } } fclose(fp); } that is what have I written for the other basic operations without parenthesis and the minus sign for the second value and it works great for the simple ones. I'm using a switch method to calculate the add, sub, mul and divide but I'm not sure how to properly use the sscanf function (if I am not using it properly) or if there is another way using a function like strtok to properly parse the parenthesis and the minus signs. Any kind help?

  Read the article

• Unity falling body pendulum behaviour

  - by user3447980

  I wonder if someone could provide some guidance. Im attempting to create a pendulum like behaviour in 2D space in Unity without using a hinge joint. Essentially I want to affect a falling body to act as though it were restrained at the radius of a point, and to be subject to gravity and friction etc. Ive tried many modifications of this code, and have come up with some cool 'strange-attractor' like behaviour but i cannot for the life of me create a realistic pendulum like action. This is what I have so far: startingposition = transform.position; //Get start position newposition = startingposition + velocity; //add old velocity newposition.y -= gravity * Time.deltaTime; //add gravity newposition = pivot + Vector2.ClampMagnitude(newposition-pivot,radius); //clamp body at radius??? velocity = newposition-startingposition; //Get new velocity transform.Translate (velocity * Time.deltaTime, Space.World); //apply to transform So im working out the new position based on the old velocity + gravity, then constraining it to a distance from a point, which is the element in the code i cannot get correct. Is this a logical way to go about it?

  Read the article

• Internet Timeouts with TP-Link TL-WN821N v2 wireless usb stick

  - by user1622959

  A short time after accessing the internet, the browser/download times out. Before the timeout, the internet works OK briefly; afterwards, the wireless is still connected with a strong signal, but every internet access results in a timeout. When I leave the PC for a while, the internet is back just to timeout again as soon as I start using it. The same happens when I reconnect to the router. Also, when I surf the internet, it takes a couple of minutes until the timeout, but when I download something, it times out in a matter of seconds. The wireless adapter works just fine in Windows and internet via ethernet cable works just fine in Ubuntu. Does anyone have the same problem or knows a solution. I use Ubuntu 12.10 x64. The problem occurs since I installed ubuntu (which was a few days ago). Here some stuff that might be usefull: serus@serus-Ubuntu-PC:~$ lsusb Bus 002 Device 002: ID 0cf3:1002 Atheros Communications, Inc. TP-Link TL-WN821N v2 802.11n [Atheros AR9170] serus@serus-Ubuntu-PC:~$ lsmod Module Size Used by carl9170 82083 0 serus@serus-Ubuntu-PC:~$ modinfo carl9170 filename: /lib/modules/3.5.0-21- generic/kernel/drivers/net/wireless/ath/carl9170/carl9170.ko alias: arusb_lnx alias: ar9170usb firmware: carl9170-1.fw description: Atheros AR9170 802.11n USB wireless serus@serus-Ubuntu-PC:~$ iwconfig wlan0 IEEE 802.11bgn ESSID:"virginmedia0137463" Mode:Managed Frequency:2.462 GHz Access Point: A0:21:B7:F8:29:B6 Bit Rate=240 Mb/s Tx-Power=20 dBm Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off Link Quality=66/70 Signal level=-44 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:1399 Invalid misc:18 Missed beacon:0 serus@serus-Ubuntu-PC:~$ sudo lshw -C network *-network description: Wireless interface physical id: 1 bus info: usb@2:2 logical name: wlan0 serial: 00:27:19:bb:00:19 capabilities: ethernet physical wireless configuration: broadcast=yes driver=carl9170 driverversion=3.5.0-21-generic firmware=1.9.4 ip=192.168.0.6 link=yes multicast=yes wireless=IEEE 802.11bgn

  Read the article

• My new favourite traceflag

  - by Dave Ballantyne

  As we are all aware, there are a number of traceflags.  Some documented, some semi-documented and some completely undocumented.  Here is one that is undocumented that Paul White(b|t) mentioned almost as an aside in one of his excellent blog posts. Much has been written about residual predicates and how a predicate can be pushed into a seek/scan operation.  This is a good thing to happen,  it does save a lot of processing from having to be done.  For the uninitiated though: If we have a simple SELECT statement such as : the process that SQL Server goes through to resolve this is : The index IX_Person_LastName_FirstName_MiddleName is navigated to find the first “Smith” For each “Smith” the middle name is checked for being a null. Two operations!, and the execution plan doesnt fully represent all the work that is being undertaken. As you can see there is only a single seek operation, the work undertaken to resolve the condition “MiddleName is not null” has been pushed into it.  This can be seen in the properties. “Seek predicate” is how the index has been navigated, and “Predicate” is the condition run over every row,  a scan inside a seek!. So the question is:  How many rows have been resolved by the seek and how many by the scan ?  How many rows did the filter remove ? Wouldn’t it be nice if this operation could be split ?  That exactly what traceflag 9130 does. Executing the query: That changes the plan rather dramatically, and should be changing how we think about the index seek itself.  The Filter operator has been added and, unsurprisingly, the condition in this is “MiddleName is not null” So it is now evident that the seek operation found 103 Smiths and 60 of those Smiths had a non-null MiddleName. This traceflag has no place on a production system,  dont even think about it

  Read the article

• How do I find information on who links to my sites?

  - by bobdobbs

  I'm trying to figure out if there's a free way to get information on backlinks to my site. I've had webmaster tools and google analytics set up for years. But I can't find access to data about site backlinks in either toolset. Webmaster tools, under 'traffic'-'links to your site' gives me the same message for all of my sites: "No data available". I haven't been able to find anything in GA that gives any information on backlinks. I've heard of using "links:" as an operator in google search, but for each of my sites, this returns either zero or very few results in cases when I know I have many backlinks. Most of the links simple aren't shown. My thinking is that google maintains a graph of who links to my site, so I figured that they might let me see it. But I can't figure out how. I've found this tool on a spammy website: http://www.backlinkwatch.com. It offers more data than google on my backlines, and offers more results in exchange for a paid subscription. The data it offers for free looks good, but the results are limited and the site has popups and obnoxious ads. So, in short: how do I get data on who links to me? Is there a free way?

  Read the article

• What can I do to utilize all my hard disk space?

  - by Twatcher

  I had windows XP running on my computer. Then I installed Ubuntu from under windows. Then I decided I wanted to have only Ubuntu also because I got a system message that I am out of disk space. I loaded up my system from a live Ubuntu DVD and deleted the partition with windows on it and also the other partition that had my data on it. I expanded the partition which I thought to be the system partition (since there was no other partition left It had ext format. After that Ubuntu was working fine and I thought I have enough disk space, since my harddrive is an 80 GB ATA Maxtor. I left a small partition as backup. But after downloading a small amount of files I got the message again, that I am running out of disk space. I don't now. How can UI make my disk space bigger? I am not used to Ubuntu's file system, and I don't have the overview on how I can actually see how much space there is left for me to use. I have basically now 1 partition with the system on it and one small backup (as far as I understand). My system is (from system utility) Ubuntu 12.04 LS 3,9 GB Intel Core 2 2,4 Ghz 80 GB ATA Maxtor Here are the results for sudo fdisk -l Disk /dev/sda: 80.0 GB, 79998918144 bytes<br> 255 heads, 63 sectors/track, 9725 cylinders, total 156247887 sectors<br> Units = sectors of 1 * 512 = 512 bytes<br> Sector size (logical/physical): 512 bytes / 512 bytes<br> I/O size (minimum/optimal): 512 bytes / 512 bytes<br> Disk identifier: 0x41ab2316<br> Device Boot Start End Blocks Id System<br> /dev/sda1 * 63 123750399 61875168+ 7 HPFS/NTFS/exFAT<br> /dev/sda2 123750400 156246015 16247808 7 HPFS/NTFS/exFAT<br>

  Read the article

• How to approach scrum task burn down when tasks have multiple peoples involvement?

  - by AgileMan

  In my company, a single task can never be completed by one individual. There is going to be a separate person to QA and Code Review each task. What this means is that each individual will give their estimates, per task, as to how much time it will take to complete. The problem is, how should I approach burn down? If I aggregate the hours together, assume the following estimate: 10 hrs - Dev time 4 hrs - QA 4 hrs - Code Review. Task Estimate = 18hrs At the end of each day I ask that the task be updated with "how much time is left until it is done". However, each person generally just thinks about their part of it. Should they mark the effort remaining, and then ADD the effort estimates to that? How are you guys doing this? UPDATE To help clarify a few things, at my organization each Task within a story requires 3 people. Someone to develop the task. (do unit tests, ect...) A QA specialist to review task (they primarily do integration and regression tests) A Tech lead to do code review. I don't think there is a wrong way or a right way, but this is our way ... and that won't be changing. We work as a team to complete even the smallest level of a story whenever possible. You cannot actually test if something works until it is dev complete, and you cannot review the quality of the code either ... so the best you can do is split things up into small logical slices so that the bare minimum functionality can be tested and reviewed as early into the process as possible. My question to those that work this way would be how to burn down a "task" when they are setup this way. Unless a Task has it's own sub-tasks (which JIRA doesn't allow) ... I'm not sure the best way to accomplish tracking "what's left" on a daily basis.

  Read the article

• Help with dual booting Windows 8.1 Professional and Ubuntu 13.10

  - by user1292548

  I recently installed a clean version of Windows 8.1 Professional on my Lenovo Y500 (with Samsung 256GB 840 Pro SSD). I have Windows all set up and running normally. I am trying to dual boot Windows 8.1 and Ubuntu 13.10, but the installation procedure don't allow me to either "Install alongside..." or shows my SSD partitions correctly when I chose the "Something Else" option. I have created a 25GB partition of free space in the Windows disk manager, but on the installation screen on Ubuntu, it shows the whole drive as a free space. I have tried installing with a burned .ISO disk and a bootable USB, the results are the same for both. Windows Disk Management screen: http://imageshack.us/a/img855/9504/59zu.jpg The Ubuntu installation screen: http://imageshack.us/a/img62/2712/9g6i.jpg I've ran into this problem before when trying to dual boot Ubuntu and Windows 7 Professional a month ago. But I gave up and never resolved the issue. --EDIT-- I tried what Eero Aaltonen suggested, and this is my result: ubuntu@ubuntu:~$ sudo parted /dev/sda print Warning: /dev/sda contains GPT signatures, indicating that it has a GPT table. However, it does not have a valid fake msdos partition table, as it should. Perhaps it was corrupted -- possibly by a program that doesn't understand GPT partition tables. Or perhaps you deleted the GPT table, and are now using an msdos partition table. Is this a GPT partition table? Yes/No? yes Model: ATA Samsung SSD 840 (scsi) Disk /dev/sda: 256GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags ubuntu@ubuntu:~$

  Read the article

• How can I triple boot Xubuntu, Ubuntu and Windows?

  - by ag.restringere

  Triple Booting Xubuntu, Ubuntu and Windows I'm an avid Xubuntu (Ubuntu + XFCE) user but I also dual boot with Windows XP. I originally created 3 partitions and wanted to use the empty one as a storage volume but now I want to install Ubuntu 12.04 LTS (the one with Unity) to do advanced testing and packaging. Ideally I would love to keep these two totally separate as I had problems in the past with conflicts between Unity and XFCE. This way I could wipe the Ubuntu w/ Unity installation if there are problems and really mess around with it. My disk looks like this: /dev/sda1 -- Windows XP /dev/sda2 -- Disk /dev/sda: 200.0 GB, 200049647616 bytes 255 heads, 63 sectors/track, 24321 cylinders, total 390721968 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 Device Boot Start End Blocks Id System /dev/sda1 * 63 78139454 39069696 7 HPFS/NTFS/exFAT /dev/sda2 78141440 156280831 39069696 83 Linux /dev/sda3 156282878 386533375 115125249 5 Extended /dev/sda4 386533376 390721535 2094080 82 Linux swap / Solaris /dev/sda5 156282880 386533375 115125248 83 Linux Keep each in it's own partition and totally separate and be able to select from each of the three systems from the GRUB boot menu... sda1 --- [Windows XP] sda2 --- [Ubuntu 12.04] "Unity" sda3(4,5) -- [Xubuntu 12.02] "Primary XFCE" What is the safest and easiest way to do this without messing my system up and requiring invasive activity?

  Read the article

• Thoughts on exception handling.

  - by AndyScott

  Was working on a windows form app (something I haven't done in a while), adding threading and logging so that it would work a little more smoothly and have a record of who did what.  I was just about at the point where I was going to check it into source control when I noticed that the Output window was showing "A first chance exception of type 'System.InvalidCastException' occurred in mscorlib.dll", so I googled it.  In reading some threads about the error, I came across the following comment and it got me thinking: "In addition, while they should be avoided if possible, exceptions are a quite legitimate part of program execution. It's their going unhandled that is a real issue, because that means crashy, crashy." How do you normally use exception handling?  I feel that exceptions are intended to handle errors in code (in my experience generally related to bad data making its way into the system).  Now don't get me wrong, I understand that exceptions happen and should be dealt with, but I feel that they are a "last resort" to keep a program from crashing, but should never be a way to pass data or continue logical processing that could be handled in standard code flow. I mention this, because I have seen it done. What do you think?

  Read the article

• Handling Types for Real and Complex Matrices in a BLAS Wrapper

  - by mga

  I come from a C background and I'm now learning OOP with C++. As an exercise (so please don't just say "this already exists"), I want to implement a wrapper for BLAS that will let the user write matrix algebra in an intuitive way (e.g. similar to MATLAB) e.g.: A = B*C*D.Inverse() + E.Transpose(); My problem is how to go about dealing with real (R) and complex (C) matrices, because of C++'s "curse" of letting you do the same thing in N different ways. I do have a clear idea of what it should look like to the user: s/he should be able to define the two separately, but operations would return a type depending on the types of the operands (R*R = R, C*C = C, R*C = C*R = C). Additionally R can be cast into C and vice versa (just by setting the imaginary parts to 0). I have considered the following options: As a real number is a special case of a complex number, inherit CMatrix from RMatrix. I quickly dismissed this as the two would have to return different types for the same getter function. Inherit RMatrix and CMatrix from Matrix. However, I can't really think of any common code that would go into Matrix (because of the different return types). Templates. Declare Matrix<T> and declare the getter function as T Get(int i, int j), and operator functions as Matrix *(Matrix RHS). Then specialize Matrix<double> and Matrix<complex>, and overload the functions. Then I couldn't really see what I would gain with templates, so why not just define RMatrix and CMatrix separately from each other, and then overload functions as necessary? Although this last option makes sense to me, there's an annoying voice inside my head saying this is not elegant, because the two are clearly related. Perhaps I'm missing an appropriate design pattern? So I guess what I'm looking for is either absolution for doing this, or advice on how to do better.

  Read the article

• Is StackOverflow making me stupid? [closed]

  - by Ayush Goyal

  Possible Duplicate: When stuck, how quickly should one resort to Stack Overflow? Its good that solution to almost every programming problem is available at my disposal, either someone has asked it before or programming gurus are waiting for me to post it..sometimes its just the matter of seconds after posting the question and someone points out the error-causing-line or proposes alternate (easier, lightweight and efficient) solution. But today it struck me "is this making me dumb?" In good (umm..not so good) old days I used to figure out the source of my problem and then work it out myself, though it used to eat up lot of time but it helped in developing my logical thinking as it used to make an impression in my mind due to which I tend to avoid that situation in future codes. Now, as soon as I encounter a problem I just give it a shot or two and head towards the community. Many times after looking at the solution it turns out that answer was all in front of me..all I needed was to take a break, hover it once and its solved. Both the approaches make me feel guilty, for wasting time when I could have asked and solved it within minutes OR being too lazy to look over it again before posting the code snippet.

  Read the article

• Accessing second hard drive

  - by Jonathan

  So I recently installed Ubuntu 10.10 64-bit on my computer. I installed it on my 60gb SSD hard drive, and in the installation it never acknowledged the existence of my second hard drive. The hard drive that I keep all my files on, and which I want to make my home folder if I can, is a Western Digital Caviar Black 1TB SATA 6Gb/s 64MB cache (WD1002FAEX). I've read the following: https://help.ubuntu.com/community/Mount but honestly cannot work out how to access the hard drive from my Ubuntu installation. I did have Windows 7 64-bit prior to installing Ubuntu. I have backed up all the files on the hard drive, but if I could just access them straight off that would be super cool. Does anyone know how I can use the second hard drive? Thank you for your help EDIT: The following directories are currently in my /dev/ folder: ati/, block/, bsg/, bus/, char/, cpu/, isk/, input/, mapper/, net/, pktcdvd/, pts/, shm/, snd/, and usb/ EDIT: Result from sudo fdisk -l Disk /dev/sda: 60.0 GB, 60022480896 bytes 255 heads, 63 sectors/track, 7297 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000d2dfd Device Boot Start End Blocks Id System /dev/sda1 * 1 6994 56174592 83 Linux /dev/sda2 6994 7298 2438145 5 Extended /dev/sda5 6994 7298 2438144 82 Linux swap / Solaris @djeykib So very close to fixing it.. unfortunately on the last command you gave it says this: $ sudo apt-get install linux-lts-backport-natty Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package linux-lts-backport-natty Checking on http://www.ubuntuupdates.org/ppas reveals that it is only available for 10.04. Looks like I'll have to unplug and re-plug hardware if I want it working still :(

  Read the article

• How do I position a 2D camera in OpenGL?

  - by Elfayer

  I can't understand how the camera is working. It's a 2D game, so I'm displaying a game map from (0, 0, 0) to (mapSizeX, 0, mapSizeY). I'm initializing the camera as follow : Camera::Camera(void) : position_(0.0f, 0.0f, 0.0f), rotation_(0.0f, 0.0f, -1.0f) {} void Camera::initialize(void) { glMatrixMode(GL_PROJECTION); glLoadIdentity(); glTranslatef(position_.x, position_.y, position_.z); gluPerspective(70.0f, 800.0f/600.0f, 1.0f, 10000.0f); gluLookAt(0.0f, 6000.0f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); } So the camera is looking down. I currently see the up right border of the map in the center of my window and the map expand to the down left border of my window. I would like to center the map. The logical thing to do should be to move the camera to eyeX = mapSizeX / 2 and the same for z. My map has 10 x 10 cases with CASE = 400, so I should have : gluLookAt((10 / 2) * CASE /* = 2000 */, 6000.0f, (10 / 2) * CASE /* = 2000 */, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f); But that doesn't move the camera, but seems to rotate it. Am I doing something wrong? EDIT : I tried that: gluLookAt(2000.0f, 6000.0f, 0.0f, 2000.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f); Which correctly moves the map in the middle of the window in width. But I can't move if correctly in height. It always returns the axis Z. When I go up, It goes down and the same for right and left. I don't see the map anymore when I do : gluLookAt(2000.0f, 6000.0f, 2000.0f, 2000.0f, 0.0f, 2000.0f, 0.0f, 1.0f, 0.0f);

  Read the article

• Trouble with speed and vectors

  - by Eegabooga

  I'm working on adding bullets to my game. Right now I can shoot bullets in the direction that I would like from a ship by getting the ship's angle: int speed = 5; int dx = -(cos(degreesToRadians(ship.angle)) * speed); // rate of change in the x direction int dy = -(sin(degreesToRadians(ship.angle)) * speed); // rate of change in the y direction bulletPosition.addX(dx); // addX(dx) is simply bulletPosition.x += dx bulletPosition.addY(dy); The ship is pretty much the exact same thing, except I use the += operator: int dx += -(cos(degreesToRadians(angle)) * 0.15) int dy += -(sin(degreesToRadians(angle)) * 0.15); shipPosition.addX(dx); shipPosition.addY(dy); I would like to be able to add the ship's velocity to the bullet's velocity, but I'm a little confused as to how should get the speed from the ship's vector. I thought that adding the ship's dx to the bullet's dx like int dx = -(cos(degreesToRadians(ship.angle)) * speed * dx) would work because I'm adding the rate of change of the ship to the rate of change of the bullet, but that doesn't work. So here's the final question: How can I get the speed of my ship and apply it to my bullet's speed? Thanks in advance for all help :)

  Read the article

• Why do I get disk I/O errors booting the 3.2 kernel on a xen vps server?

  - by Doug

  I have a xen vps, which I just upgraded to the new LTS 12 Precise Pangolin. However, I see this error on booting: [ 12.848076] end_request: I/O error, dev xvda, sector 12841 [ 12.848093] end_request: I/O error, dev xvda, sector 12841 [ 12.848103] Buffer I/O error on device xvda1, logical block 1605 [ 12.848110] lost page write due to I/O error on xvda1 [ 12.848129] Aborting journal on device xvda1. Results in / being mounted read-only. Reboot: [ 3.087257] EXT3-fs (xvda1): warning: ext3_clear_journal_err: Marking fs in need of filesystem check. [ 3.087677] EXT3-fs (xvda1): recovery complete [ 3.088514] EXT3-fs (xvda1): mounted filesystem with ordered data mode Begin: Running /scripts/local-bottom ... done. done. Begin: Running /scripts/init-bottom ... done. fsck from util-linux 2.20.1 PRGMRDISK1 contains a file system with errors, check forced. Checking disk drives for errors. This may take several minutes. Press C to cancel all checks in progress PRGMRDISK1: ***** REBOOT LINUX ***** PRGMRDISK1: 371152/6001184 files (2.8% non-contiguous), 4727949/12000000 blocks mountall: fsck / [308] terminated with status 3 mountall: System must be rebooted: / [ 151.566949] Restarting system. Name ID Mem VCPUs State Time(s) shadowmint 236 2048 1 --p--- 0.0 Reboot - back to 1. This is definitely an issue with the 3.2 kernel, because booting the 3.0.0 or 2.6.38 kernel series make this issue magically disappear. I'm certain this is some kind of weird xen thing, but no idea. Anyone? Anyhow, until this is resolve I strongly recommend against upgrading if you're running a xen server.

  Read the article

• Wireless drivers

  - by Kencer

  The results for my laptop are as below. How will i install wireless drivers and graphics? $ lspci 00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09) 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 00:14.0 USB controller: Intel Corporation Panther Point USB xHCI Host Controller (rev 04) 00:16.0 Communication controller: Intel Corporation Panther Point MEI Controller #1 (rev 04) 00:1a.0 USB controller: Intel Corporation Panther Point USB Enhanced Host Controller #2 (rev 04) 00:1b.0 Audio device: Intel Corporation Panther Point High Definition Audio Controller (rev 04) 00:1c.0 PCI bridge: Intel Corporation Panther Point PCI Express Root Port 1 (rev c4) 00:1c.1 PCI bridge: Intel Corporation Panther Point PCI Express Root Port 2 (rev c4) 00:1c.3 PCI bridge: Intel Corporation Panther Point PCI Express Root Port 4 (rev c4) 00:1d.0 USB controller: Intel Corporation Panther Point USB Enhanced Host Controller #1 (rev 04) 00:1f.0 ISA bridge: Intel Corporation Panther Point LPC Controller (rev 04) 00:1f.2 SATA controller: Intel Corporation Panther Point 6 port SATA Controller [AHCI mode] (rev 04) 00:1f.3 SMBus: Intel Corporation Panther Point SMBus Controller (rev 04) 02:00.0 Network controller: Broadcom Corporation Device 4365 (rev 01) 03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 07) $ sudo lshw -c network *-network UNCLAIMED description: Network controller product: Broadcom Corporation vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:02:00.0 version: 01 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list configuration: latency=0 resources: memory:f0500000-f0507fff *-network description: Ethernet interface product: RTL8111/8168B PCI Express Gigabit Ethernet controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:03:00.0 logical name: eth0 version: 07 serial: 3c:97:0e:85:c0:0d size: 100Mbit/s capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=rtl8168e-3_0.0.4 03/27/12 ip=172.16.96.36 latency=0 link=yes multicast=yes port=MII speed=100Mbit/s resources: irq:43 ioport:2000(size=256) memory:f0404000-f0404fff memory:f0400000-f0403fff $ rfkill list all 0: tpacpi_bluetooth_sw: Bluetooth Soft blocked: no Hard blocked: no

  Read the article

< Previous Page | 107 108 109 110 111 112 113 114 115 116 117 118  | Next Page >