Search Results

Search found 7914 results on 317 pages for 'invalid argument'.

Page 219/317 | < Previous Page | 215 216 217 218 219 220 221 222 223 224 225 226  | Next Page >

• I can't install Ubuntu 12.04.1 on iMac G5

  - by user89004

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

  Read the article

• Why is Double.Parse so slow?

  - by alexhildyard

  I was recently investigating a bottleneck in one of my applications, which read a CSV file from disk using a TextReader a line at a time, split the tokens, called Double.Parse on each one, then shunted the results into an object list. I was surprised to find it was actually the Double.Parse which seemed to be taking up most of the time.Googling turned up this, which is a little unfocused in places but throws out some excellent ideas:It makes more sense to work with binary format directly, rather than coerce strings into doublesThere is a significant performance improvement in composing doubles directly from the byte stream via long intermediariesString.Split is inefficient on fixed length recordsIn fact it turned out that my problem was more insidious and also more mundane -- a simple case of bad data in, bad data out. Since I had been serialising my Doubles as strings, when I inadvertently divided by zero and produced a "NaN", this of course was serialised as well without error. And because I was reading in using Double.Parse, these "NaN" fields were also (correctly) populating real Double objects without error. The issue is that Double.Parse("NaN") is incredibly slow. In fact, it is of the order of 2000x slower than parsing a valid double. For example, the code below gave me results of 357ms to parse 1000 NaNs, versus 15ms to parse 100,000 valid doubles.            const int invalid_iterations = 1000;            const int valid_iterations = invalid_iterations * 100;            const string invalid_string = "NaN";            const string valid_string = "3.14159265";            DateTime start = DateTime.Now;                        for (int i = 0; i < invalid_iterations; i++)            {                double invalid_double = Double.Parse(invalid_string);            }            Console.WriteLine(String.Format("{0} iterations of invalid double, time taken (ms): {1}",                invalid_iterations,                ((TimeSpan)DateTime.Now.Subtract(start)).Milliseconds            ));            start = DateTime.Now;            for (int i = 0; i < valid_iterations; i++)            {                double valid_double = Double.Parse(valid_string);            }            Console.WriteLine(String.Format("{0} iterations of valid double, time taken (ms): {1}",                valid_iterations,                ((TimeSpan)DateTime.Now.Subtract(start)).Milliseconds            )); I think the moral is to look at the context -- specifically the data -- as well as the code itself. Once I had corrected my data, the performance of Double.Parse was perfectly acceptable, and while clearly it could have been improved, it was now sufficient to my needs.

  Read the article

• Should Exterrnal USB hard drive auto mount Ubuntu 12.04.01 LTS

  - by Chris Good

  I want to have external USB hard drives automatically mounted when plugged in. I have 2 drives exactly the same except for volume label. They both have the same UUID. I want to be easily able to swap them as I'm using them for backups and want to keep 1 at home for off site backup. I've set up the /etc/fstab so they should mount at different places based on their volume label: /etc/fstab : LABEL=Passport1 /media/Passport1 ntfs defaults,windows_names,locale=en_US.utf8 0 0 LABEL=Passport2 /media/Passport2 ntfs defaults,windows_names,locale=en_US.utf8 0 0 blkid shows : ... /dev/sdc1: LABEL="Passport2" UUID="4E1AEA7B1AEA6007" TYPE="ntfs" /dev/sdd1: LABEL="Passport1" UUID="4E1AEA7B1AEA6007" TYPE="ntfs" They both mount automatically during reboot but do not mount when just plugged in to a running system. I've read lots of stuff about this, much of it is old so I'm not sure if it applies. I've read some stuff that says the mounts should happen automatically when plugged in, and lots of other stuff that says you have to install other software to make this happen, although much of it just seems to set up the fstab. What's the real story? Here is /var/log/syslog when drive is plugged in: Dec 14 11:22:58 ausyvutims1 kernel: [66221.300196] usb 1-1: new high-speed USB device number 6 using ehci_hcd Dec 14 11:22:58 ausyvutims1 mtp-probe: checking bus 1, device 6: "/sys/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1" Dec 14 11:22:58 ausyvutims1 mtp-probe: bus: 1, device: 6 was not an MTP device Dec 14 11:22:58 ausyvutims1 kernel: [66221.656020] scsi7 : usb-storage 1-1:1.0 Dec 14 11:22:59 ausyvutims1 kernel: [66222.661534] scsi 7:0:0:0: Direct-Access WD My Passport 0748 1016 PQ: 0 ANSI: 6 Dec 14 11:22:59 ausyvutims1 kernel: [66222.666466] scsi 7:0:0:1: Enclosure WD SES Device 1016 PQ: 0 ANSI: 6 Dec 14 11:22:59 ausyvutims1 kernel: [66222.667739] sd 7:0:0:0: Attached scsi generic sg3 type 0 Dec 14 11:22:59 ausyvutims1 kernel: [66222.667913] ses 7:0:0:1: Attached Enclosure device Dec 14 11:22:59 ausyvutims1 kernel: [66222.668047] ses 7:0:0:1: Attached scsi generic sg4 type 13 Dec 14 11:22:59 ausyvutims1 kernel: [66222.678473] sd 7:0:0:0: [sdc] 1953458176 512-byte logical blocks: (1.00 TB/931 GiB) Dec 14 11:22:59 ausyvutims1 kernel: [66222.687700] sd 7:0:0:0: [sdc] Write Protect is off Dec 14 11:22:59 ausyvutims1 kernel: [66222.687705] sd 7:0:0:0: [sdc] Mode Sense: 47 00 10 08 Dec 14 11:22:59 ausyvutims1 kernel: [66222.701076] sd 7:0:0:0: [sdc] No Caching mode page present Dec 14 11:22:59 ausyvutims1 kernel: [66222.701081] sd 7:0:0:0: [sdc] Assuming drive cache: write through Dec 14 11:22:59 ausyvutims1 kernel: [66222.738062] sd 7:0:0:0: [sdc] No Caching mode page present Dec 14 11:22:59 ausyvutims1 kernel: [66222.738068] sd 7:0:0:0: [sdc] Assuming drive cache: write through Dec 14 11:22:59 ausyvutims1 kernel: [66222.754558] sdc: sdc1 Dec 14 11:22:59 ausyvutims1 kernel: [66222.792006] sd 7:0:0:0: [sdc] No Caching mode page present Dec 14 11:22:59 ausyvutims1 kernel: [66222.792012] sd 7:0:0:0: [sdc] Assuming drive cache: write through Dec 14 11:22:59 ausyvutims1 kernel: [66222.792016] sd 7:0:0:0: [sdc] Attached SCSI disk Dec 14 11:22:59 ausyvutims1 ata_id[16971]: HDIO_GET_IDENTITY failed for '/dev/sdc': Invalid argument Thanks for any help offered

  Read the article

• System freezes while not in use, how do I fix this?

  - by PHLAK

  Bare with me, the following is a bit winded. I have Ubuntu 10.10 Desktop 64-bit installed on my laptop and up until a few weeks ago it has been running great. Then one day, while I was not using the laptop it froze. I was logged in as my user but had locked the screen locked and closed the lid. I didn't notice that it had frozen until I opened the lid and wiggled the mouse to try and log in. The screen remained black and I got no response. I immediately tried Alt + F2, F3, F4, etc. but got no response. The only thing I could do was hold the power button to power off the machine. The freezing has happened as quickly as within 10-20 minutes of the system being logged off and lid closed and as long as 4-6 hours. My machine is NOT configured to go into standby when plugged in and this has happened both on AC power and battery. Troubleshooting I have performed: I uninstalled programs I knew that I had installed between when it was working fine and having problems. Those programs were CrashPlan, Shutter and Conky. After uninstalling ALL of these programs the freezing still occurs. Next, I decided to SSH into the machine from my desktop and leave an htop and tail of the syslog running. Here are screenshots of the last thing shown on both when the system froze: htop, syslog Here is a dump of my syslog after another freeze. The freeze happened at 9:14 and I didn't notice it until about 10 minutes later and rebooted, hence the 10 minute gap from 9:14 to 9:24. In the above syslog dump I noticed a lot of NVRM: os_raise_smp_barrier(), invalid context! and upon investigating that message learned it was from the proprietary Nvidia driver I had installed. Thinking this could be part of the problem I uninstalled the Nvidia driver and reverted to using the Nouveau driver. The computer still froze after a few hours. Lastly, thinking the problem could be caused by overheating I used compressed air to blow out any dust in the CPU vents and all other openings on the laptop. None of the above troubleshooting has helped and the freezing still occurs. What other steps can I take to troubleshoot and/or fix this problem? Note: Yesterday X started to eat up a lot of CPU power and eventually froze my system while I was forwarding an X session over SSH (from another PC to my laptop). I'm unsure if this is related or not as it doesn't match any of the symptoms of the problem above. Aside from this, the system has never frozen while in use, even under heavy load. EDIT: I just ran Memtest86+ and it made it through two passes without any errors. Just eliminating possible causes here.

  Read the article

• How to suggest using an ORM instead of stored procedures?

  - by Wayne M

  I work at a company that only uses stored procedures for all data access, which makes it very annoying to keep our local databases in sync as every commit we have to run new procs. I have used some basic ORMs in the past and I find the experience much better and cleaner. I'd like to suggest to the development manager and rest of the team that we look into using an ORM Of some kind for future development (the rest of the team are only familiar with stored procedures and have never used anything else). The current architecture is .NET 3.5 written like .NET 1.1, with "god classes" that use a strange implementation of ActiveRecord and return untyped DataSets which are looped over in code-behind files - the classes work something like this: class Foo { public bool LoadFoo() { bool blnResult = false; if (this.FooID == 0) { throw new Exception("FooID must be set before calling this method."); } DataSet ds = // ... call to Sproc if (ds.Tables[0].Rows.Count > 0) { foo.FooName = ds.Tables[0].Rows[0]["FooName"].ToString(); // other properties set blnResult = true; } return blnResult; } } // Consumer Foo foo = new Foo(); foo.FooID = 1234; foo.LoadFoo(); // do stuff with foo... There is pretty much no application of any design patterns. There are no tests whatsoever (nobody else knows how to write unit tests, and testing is done through manually loading up the website and poking around). Looking through our database we have: 199 tables, 13 views, a whopping 926 stored procedures and 93 functions. About 30 or so tables are used for batch jobs or external things, the remainder are used in our core application. Is it even worth pursuing a different approach in this scenario? I'm talking about moving forward only since we aren't allowed to refactor the existing code since "it works" so we cannot change the existing classes to use an ORM, but I don't know how often we add brand new modules instead of adding to/fixing current modules so I'm not sure if an ORM is the right approach (too much invested in stored procedures and DataSets). If it is the right choice, how should I present the case for using one? Off the top of my head the only benefits I can think of is having cleaner code (although it might not be, since the current architecture isn't built with ORMs in mind so we would basically be jury-rigging ORMs on to future modules but the old ones would still be using the DataSets) and less hassle to have to remember what procedure scripts have been run and which need to be run, etc. but that's it, and I don't know how compelling an argument that would be. Maintainability is another concern but one that nobody except me seems to be concerned about.

  Read the article

• Real-Time Multi-User Gaming Platform

  - by Victor Engel

  I asked this question at Stack Overflow but was told it's more appropriate here, so I'm posting it again here. I'm considering developing a real-time multi-user game, and I want to gather some information about possibilities before I do some real development. I've thought about how best to ask the question, and for simplicity, the best way that occurred to me was to make an analogy to the field (or playground) game darebase. In the field game of darebase, there are two or more bases. To start, there is one team on each base. The game is a fancy game of tag. When two people meet out in the field, the person who left his base most recently timewise captures the other person. They then return to that person's base. Play continues until everyone is part of the same team. So, analogizing this to an online computer game, let's suppose there are an indefinite number of bases. When a person starts up the game, he has a team that is located at, for example, his current GPS coordinates. It could be a virtual world, but for sake of argument, let's suppose the virtual world corresponds to the player's actual GPS coordinates. The game software then consults the database to see where the closest other base is that is online, and the two teams play their game of virtual tag. Note that the user of the other base could have a different base than the one run by the current user as the closest base to him, in which case, he would be in two simultaneous battles, one with each base. When they go offline, the state of their players is saved on a server somewhere. Game logic calls for the players to have some automaton-logic of some sort, so they can fend for themselves in a limited way using basic rules, until their user goes online again. The user doesn't control the players' movements directly, but issues general directives that influence the players' movement logic. I think this analogy is good enough to frame my question. What sort of platforms are available to develop this sort of game? I've been looking at smartfoxserver, but I'm not convinced yet that it is the best option or even that it will work at all. One possibility, of course, would be to roll out my own web server, but I'd rather not do that if there is an existing service out there already that I could tap into. I will be developing for iOS devices at first. So any suggestions would be greatly appreciated. I think I need to establish the architecture first before proceeding with this project. Note that darbase is not the game I intend to implement, but, upon reflection, that might not be a bad idea either.

  Read the article

• SQL SERVER – Fix: Error: 147 An aggregate may not appear in the WHERE clause unless it is in a subquery contained in a HAVING clause or a select list, and the column being aggregated is an outer reference

  - by pinaldave

  Everybody was beginner once and I always like to get involved in the questions from beginners. There is a big difference between the question from beginner and question from advanced user. I have noticed that if an advanced user gets an error, they usually need just a small hint to resolve the problem. However, when a beginner gets error he sometimes sits on the error for a long time as he/she has no idea about how to solve the problem as well have no idea regarding what is the capability of the product. I recently received a very novice level question. When I received the problem I quickly see how the user was stuck. When I replied him with the solution, he wrote a long email explaining how he was not able to solve the problem. He thanked multiple times in the email. This whole thing inspired me to write this quick blog post. I have modified the user’s question to match the code with AdventureWorks as well simplified so it contains the core content which I wanted to discuss. Problem Statement: Find all the details of SalesOrderHeaders for the latest ShipDate. He comes up with following T-SQL Query: SELECT * FROM [Sales].[SalesOrderHeader] WHERE ShipDate = MAX(ShipDate) GO When he executed above script it gave him following error: Msg 147, Level 15, State 1, Line 3 An aggregate may not appear in the WHERE clause unless it is in a subquery contained in a HAVING clause or a select list, and the column being aggregated is an outer reference. He was not able to resolve this problem, even though the solution was given in the query description itself. Due to lack of experience he came up with another version of above query based on the error message. SELECT * FROM [Sales].[SalesOrderHeader] HAVING ShipDate = MAX(ShipDate) GO When he ran above query it produced another error. Msg 8121, Level 16, State 1, Line 3 Column ‘Sales.SalesOrderHeader.ShipDate’ is invalid in the HAVING clause because it is not contained in either an aggregate function or the GROUP BY clause. What he wanted actually was the SalesOrderHeader all the Sales shipped on the last day. Based on the problem statement what the right solution is as following, which does not generate error. SELECT * FROM [Sales].[SalesOrderHeader] WHERE ShipDate = (SELECT MAX(ShipDate) FROM [Sales].[SalesOrderHeader]) Well, that’s it! Very simple. With SQL Server there are always multiple solution to a single problem. Is there any other solution available to the problem stated? Please share in the comment. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Error Messages, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

  Read the article

• Is code like this a "train wreck" (in violation of Law of Demeter)?

  - by Michael Kjörling

  Browsing through some code I've written, I came across the following construct which got me thinking. At a first glance, it seems clean enough. Yes, in the actual code the getLocation() method has a slightly more specific name which better describes exactly which location it gets. service.setLocation(this.configuration.getLocation().toString()); In this case, service is an instance variable of a known type, declared within the method. this.configuration comes from being passed in to the class constructor, and is an instance of a class implementing a specific interface (which mandates a public getLocation() method). Hence, the return type of the expression this.configuration.getLocation() is known; specifically in this case, it is a java.net.URL, whereas service.setLocation() wants a String. Since the two types String and URL are not directly compatible, some sort of conversion is required to fit the square peg in the round hole. However, according to the Law of Demeter as cited in Clean Code, a method f in class C should only call methods on C, objects created by or passed as arguments to f, and objects held in instance variables of C. Anything beyond that (the final toString() in my particular case above, unless you consider a temporary object created as a result of the method invocation itself, in which case the whole Law seems to be moot) is disallowed. Is there a valid reasoning why a call like the above, given the constraints listed, should be discouraged or even disallowed? Or am I just being overly nitpicky? If I were to implement a method URLToString() which simply calls toString() on a URL object (such as that returned by getLocation()) passed to it as a parameter, and returns the result, I could wrap the getLocation() call in it to achieve exactly the same result; effectively, I would just move the conversion one step outward. Would that somehow make it acceptable? (It seems to me, intuitively, that it should not make any difference either way, since all that does is move things around a little. However, going by the letter of the Law of Demeter as cited, it would be acceptable, since I would then be operating directly on a parameter to a function.) Would it make any difference if this was about something slightly more exotic than calling toString() on a standard type? When answering, do keep in mind that altering the behavior or API of the type that the service variable is of is not practical. Also, for the sake of argument, let's say that altering the return type of getLocation() is also impractical.

  Read the article

• Problem getting GOBI 2000 HS to work

  - by Zypher

  I've been trying to get my integrated GOBI WWAN card to work under 10.10 for a while now. I was able to get the network manager to see the card after installing the gobi-loader package. I was able to setup the connection, but i cannot establish a connection to Verizon. Below is the output from /var/log/daemon.log as i try to connect. Oct 19 14:29:42 gbeech-x201 AptDaemon: INFO: Quiting due to inactivity Oct 19 14:29:42 gbeech-x201 AptDaemon: INFO: Shutdown was requested Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) starting connection 'Verizon connection' Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> (ttyUSB0): device state change: 3 -> 4 (reason 0) Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) scheduled... Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) started... Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> (ttyUSB0): device state change: 4 -> 6 (reason 0) Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) complete. Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) scheduled... Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) started... Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> (ttyUSB0): device state change: 6 -> 4 (reason 0) Oct 19 14:33:45 gbeech-x201 NetworkManager[1105]: <info> Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) complete. Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <warn> CDMA connection failed: (32) No service Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <info> (ttyUSB0): device state change: 4 -> 9 (reason 0) Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <info> Marking connection 'Verizon connection' invalid. Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <warn> Activation (ttyUSB0) failed. Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <info> (ttyUSB0): device state change: 9 -> 3 (reason 0) Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <info> (ttyUSB0): deactivating device (reason: 0). Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <info> Policy set 'Auto SO-GUEST' (wlan0) as default for IPv4 routing and DNS. Oct 19 14:34:46 gbeech-x201 NetworkManager[1105]: <info> Policy set 'Auto SO-GUEST' (wlan0) as default for IPv4 routing and DNS.

  Read the article

• Why would I learn C++11, having known C and C++?

  - by Shahbaz

  I am a programmer in C and C++, although I don't stick to either language and write a mixture of the two. Sometimes having code in classes, possibly with operator overloading, or templates and the oh so great STL is obviously a better way. Sometimes use of a simple C function pointer is much much more readable and clear. So I find beauty and practicality in both languages. I don't want to get into the discussion of "If you mix them and compile with a C++ compiler, it's not a mix anymore, it's all C++" I think we all understand what I mean by mixing them. Also, I don't want to talk about C vs C++, this question is all about C++11. C++11 introduces what I think are significant changes to how C++ works, but it has introduced many special cases that change how different features behave in different circumstances, placing restrictions on multiple inheritance, adding lambda functions, etc. I know that at some point in the future, when you say C++ everyone would assume C++11. Much like when you say C nowadays, you most probably mean C99. That makes me consider learning C++11. After all, if I want to continue writing code in C++, I may at some point need to start using those features simply because my colleagues have. Take C for example. After so many years, there are still many people learning and writing code in C. Why? Because the language is good. What good means is that, it follows many of the rules to create a good programming language. So besides being powerful (which easy or hard, almost all programming languages are), C is regular and has few exceptions, if any. C++11 however, I don't think so. I'm not sure that the changes introduced in C++11 are making the language better. So the question is: Why would I learn C++11? Update: My original question in short was: "I like C++, but the new C++11 doesn't look good because of this and this and this. However, deep down something tells me I need to learn it. So, I asked this question here so that someone would help convince me to learn it." However, the zealous people here can't tolerate pointing out a flaw in their language and were not at all constructive in this manner. After the moderator edited the question, it became more like a "So, how about this new C++11?" which was not at all my question. Therefore, in a day or too I am going to delete this question if no one comes up with an actual convincing argument. P.S. If you are interested in knowing what flaws I was talking about, you can edit my question and see the previous edits.

  Read the article

• C# 5: At last, async without the pain

  - by Alex.Davies

  For me, the best feature in Visual Studio 11 is the async and await keywords that come with C# 5. I am a big fan of asynchronous programming: it frees up resources, in particular the thread that a piece of code needs to run in. That lets that thread run something else, while waiting for your long-running operation to complete. That's really important if that thread is the UI thread, or if it's holding a lock because it accesses some data structure. Before C# 5, I think I was about the only person in the world who really cared about asynchronous programming. The trouble was that you had to go to extreme lengths to make code asynchronous. I would forever be writing methods that, instead of returning a value, accepted an extra argument that is a "continuation". Then, when calling the method, I'd have to pass a lambda in to it, which contained all the stuff that needed to happen after the method finished. Here is a real snippet of code that is in .NET Demon: m_BuildControl.FilterEnabledForBuilding(     projects,     enabledProjects = m_OutOfDateProjectFinder.FilterNeedsBuilding(         enabledProjects,         newDirtyProjects =         {             // Mark any currently broken projects as dirty             newDirtyProjects.UnionWith(m_BrokenProjects);             // Copy what we found into the set of dirty things             m_DirtyProjects = newDirtyProjects;             RunSomeBuilds();         })); It's just obtuse. Who puts a lambda inside a lambda like that? Well, me obviously. But surely enabledProjects should just be the return value of FilterEnabledForBuilding? And newDirtyProjects should just be the return value of FilterNeedsBuilding? C# 5 async/await lets you write asynchronous code without it looking so stupid. Here's what I plan to change that code to, once we upgrade to VS 11: var enabledProjects = await m_BuildControl.FilterEnabledForBuilding(projects); var newDirtyProjects = await m_OutOfDateProjectFinder.FilterNeedsBuilding(enabledProjects); // Mark any currently broken projects as dirty newDirtyProjects.UnionWith(m_BrokenProjects); // Copy what we found into the set of dirty things m_DirtyProjects = newDirtyProjects; RunSomeBuilds(); Much easier to read! But how is this the same code? If we were on the UI thread, doesn't the UI thread have to block while FilterEnabledForBuilding runs? No, it doesn't, and that's the magic of the await keyword! It cuts your method up into its constituent pieces, much like I did manually with lambdas before. When you run it, only the piece up to the first await actually runs. The rest is passed to FilterEnabledForBuilding as a continuation, which will get called back whenever that method is finished. In the meantime, our thread returns, and can go back to making the UI responsive, or whatever else threads do in their spare time. This is actually a massive simplification, and if you're interested in all the gory details, and speed hacks that the await keyword actually does for you, I recommend Jon Skeet's blog posts about it.

  Read the article

• How can I get my ATI / AMD drivers to work with any kernel above 3.2.0.x?

  - by TorakTu

  How can I get my ATI / AMD drivers to work with any kernel above 3.2.0.x ? WHAT DID WORK Installed original AMD64 version of Ubuntu 12.04 ISO image. Burned DVD and installed which shown kernel 3.2.0-23 to begin with. Got 5.1 surround sound working. Got ATI ( Now its AMD ) video drivers installed for my Radeon HD R6870 Video card from AMD's website. fglrxinfo came up and reported as normal. THE PROBLEM Kernel 3.2.0.x kept locking up so I tried higher kernel versions. But ATI / AMD Drivers do not install on any kernel Above 3.2.0.x WHAT I HAVE TRIED I have gone over this tutorial many times ( https://help.ubuntu.com/community/BinaryDriverHowto/ATI ) and it doesn't work on ANY kernel except 3.2.0.x. The problems I am having here are that the ATI / AMD drivers working for the 12.04 Precise with kernel 3.2.0-23 and 24, But the computer kept locking up. Although all my games would work, the lock ups were random and were constant. So I looked all over the web for 3 days trying to find an answer and the lock up issue was said to just update the kernel. So I did. Have tried many kernels. All of them .. no lock ups. BUT the Restricted AMD drivers from the AMD website will not install. And none of the OpenSource AMD drivers have EVER installed no matter what Kernel or version I tried. EXAMPLE OUTPUT OF 3D TYPE OF ERRORS Javax.media.opengl.GLException: glXGetConfig failed: error code GLX_NO_EXTENSION at com.sun.opengl.impl.x11.X11GLDrawableFactory.glXGetConfig(X11GLDrawableFactory.java:651) at com.sun.opengl.impl.x11.X11GLDrawableFactory.xvi2GLCapabilities(X11GLDrawableFactory.java:350) at com.sun.opengl.impl.x11.X11GLDrawableFactory.chooseGraphicsConfiguration(X11GLDrawableFactory.java:174) at javax.media.opengl.GLCanvas.chooseGraphicsConfiguration(GLCanvas.java:520) at javax.media.opengl.GLCanvas.<init>(GLCanvas.java:131) at haven.HavenPanel.<init>(HavenPanel.java:68) at haven.HavenPanel.<init>(HavenPanel.java:78) at haven.MainFrame.<init>(MainFrame.java:182) at haven.MainFrame.main2(MainFrame.java:306) at haven.MainFrame.access$100(MainFrame.java:34) at haven.MainFrame$7.run(MainFrame.java:360) at java.lang.Thread.run(Thread.java:722) And of course this is what fglrxinfo shows : X Error of failed request: BadRequest (invalid request code or no such operation) Major opcode of failed request: 139 (ATIFGLEXTENSION) Minor opcode of failed request: 66 () Serial number of failed request: 13 Current serial number in output stream: 13 EDIT : I forgot to mention that I DID look at this post over the last few days and it did not help.

  Read the article

• How can I achieve a 3D-like effect with spritebatch's rotation and scale parameters

  - by Alic44

  I'm working on a 2d game with a top-down perspective similar to Secret of Mana and the 2D Final Fantasy games, with one big difference being that it's an action rpg using a 3-dimensional physics engine. I'm trying to draw an aimer graphic (basically an arrow) at my characters' feet when they're aiming a ranged weapon. At first I just converted the character's aim vector to radians and passed that into spritebatch, but there was a problem. The position of every object in my world is scaled for perspective when it's drawn to the screen. So if the physics engine coordinates are (1, 0, 1), the screen coords are actually (1, .707) -- the Y and Z axis are scaled by a perspective factor of .707 and then added together to get the screen coordinates. This meant that the direction the aimer graphic pointed (thanks to its rotation value passed into spritebatch) didn't match up with the direction the projectile actually traveled over time. Things looked fine when the characters fired left, right, up, or down, but if you fired on a diagonal the perspective of the physics engine didn't match with the simplistic way I was converting the character's aim direction to a screen rotation. Ok, fast forward to now: I've got the aimer's rotation matched up with the path the projectile will actually take, which I'm doing by decomposing a transform matrix which I build from two rotation matrices (one to represent the aimer's rotation, and one to represent the camera's 45 degree rotation on the x axis). My question is, is there a way to get not just rotation from a series of matrix transformations, but to also get a Vector2 scale which would give the aimer the appearance of being a 3d object, being warped by perspective? Orthographic perspective is what I'm going for, I think. So, the aimer arrow would get longer when facing sideways, and shorter when facing north and south because of the perspective. At the same time, it would get wider when facing north and south, and less wide when facing right or left. I'd like to avoid actually drawing the aimer texture in 3d because I'm still using spritebatch's layerdepth parameter at this point in my project, and I don't want to have to figure out how to draw a 3d object within the depth sorting system I already have. I can provide code and more details if this is too vague as a question... This is my first post on stack exchange. Thanks a lot for reading! Note: (I think) I realize it can't be a technically correct 3D perspective, because the spritebatch's vector2 scaling argument doesn't allow for an object to be skewed the way it actually should be. What I'm really interested in is, is there a good way to fake the effect, or should I just drop it and not scale at all? Edit to clarify without the help of a picture (apparently I can't post them yet): I want the aimer arrow to look like it has been painted on the ground at the character's feet, so it should appear to be drawn on the ground plane (in my case the XZ plane) which should be tilted at a 45 degree angle (around the X axis) from the viewing perspective. Alex

  Read the article

• Live-Ubuntu 12.04 ran fine, now stopped booting!

  - by user89743

  I've seen similar problems to this several times in the forum, but mine is a bit different, so the other posts I saw were no help to me. When I boot Ubuntu 12.04 64-bit from live-SD-card (3GB persistence) I suddenly get this error: (initramfs) mount: mounting /dev/loop0 on //filesystem.squashfs failed: Invalid argument Can not mount /dev/loop/0 (/cdrom/casper/filesystem.squashfs) on //filesystem.squashfs (it says I can type "help" for commands, but I don't know anything about how to go from there, totally new to linux) The reason I say my case is different is because my Ubuntu worked fine for over a week, even pretty fast, and now this problem happened. Before that I used to run my live ubuntu from USB sticks but that was slower (especially when booting which took 15 minutes from USB stick!). Also I kept getting the same above problem after a while when booting and had to re-create a live USB linux several times. Installing on harddrive is not an option because my harddrive has physical damage and getting a replacement will take a while, therefore I can only use live-USB or live-SD-card Ubuntu. As I said I used Ubuntu without problems for more than a week, before that as well for several weeks on USB sticks, but the above problem occured sooner or later. This time I paid attention to when it happened: I was rebooting my computer (HP 620 laptop, 4 GB RAM, 64 bit system) from SD flash card and when I was booting I selected F6 and then the first option "no acpi" or something like that...I had used it before and noticed it slowed down the time it took Linux to use. This time it caused this error. Now even when I boot normally/default I get this error. Now I'm accessing Ubuntu from my USB stick without persistence file, when I check my SD card, all the files mentioned in the error message are there and the filesystem.squashfs is 691.2 MB so nothing seems to have been deleted by accident. (I have already made many changes/downloaded programs to my SD card persistent Ubuntu and would hope to loose them, since downloading is expensive for me, and since the problem seems to re-occur...) Can anyone help me, preferably without having to create another startup disk on my SD card? I'm totally new to this. Sorry for the long posts, just didn't know what info is relevant and what isnt! Kon

  Read the article

• Good, simple reasons for having multiple environments

  - by smp7d

  Throughout my career I had worked at companies that had a collection of different environments for different purposes. We always had more or less our desktop environment, a test environment, a QA environment, a staging environment and a production environment. This went for both servers/applications and any data sources we were using. When I started at my current company I found that 90% of the apps were either developed on a desktop environment against production data sources or developed directly on the production server depending on the platform. I wasn't fazed because I was hired in part to make changes to improve the way the development team functioned, which was clear from my interview process. We slowly started to turn the philosophy and pretty soon, most of the apps could be run in either a desktop, test or production environment. Not too long after that staging came around as well. Now most of our developers see the benefit of this methodology and defend it vigilantly. However, we have a number of legacy apps that never got migrated. We also have a number of legacy programmers who think of this as a waste of time. Unfortunately, we got lip service but never full buy-in from management. We got what we thought was a commitment to invest substantially in this about a year ago, but nothing materialized despite the considerable planning that we put into it. Now we are finding that we need more and more environments. We need help from the server/network administration teams for setup and we need participation from the business stakeholders to support the release cycle. We are at a place now where a project can function what I consider "normally" only if you have the right people on the project and the time to set up the proper environments. I'd love to present a complete argument, but management really has no time and interest in hearing me out until there is a critical issue. I can't really articulate the benefits simply as it always just seemed second nature to me. I was wondering if there are any good, simple, irrefutable reasons for the separation of environments that would get managers with no development experience to get behind this idea. Are there any good resources/literature on the topic?

  Read the article

• To make or not to make...python-nautilus a dependency?

  - by George Edison

  That is the question! Okay, all silliness aside, I really am forced to make a difficult decision here. My application is written in C++ and allows other scripts to invoke methods via XML-RPC. One of these scripts is a Nautilus extension written in Python. The extension is packaged with the rest of the application and copied to the appropriate place when installed (/usr/share/nautilus-python/extensions). Now the problem is that the Nautilus extension requires the python-nautilus package to be installed to be operational. So therefore I have three options: Make the python-nautilus package a dependency. This option will ensure that anyone who installs my package will be able to use the Nautilus extension. However, this option will not be attractive to XFCE or KDE users - a ton of python-nautilus's dependencies will be installed on their machines and take up a lot of space - even if they never use Nautilus. Put the python-nautilus package in the suggests: or recommends: field. This option provides the end-user with a way to avoid installing the python-nautilus package (by providing the --no-install-suggests or --no-install-recommends argument to apt-get). However, this won't work when the user installs the package in the Software Center. (I always get mixed up as to which of those two fields are installed by default.) Prompt the user when the application is installed or first launched. This option is more complicated than the others but offers the best compromise between making it easy for the user to install python-nautilus (without going into a technical explanation) and not installing it when the user doesn't need it (or want it). I guess the best way to implement this is a simple prompt that invokes apt-get if the user would like the package installed. Don't install the package at all. This option ensures that nobody has python-nautilus installed on their machine unless they want it. However, this also means that my Nautilus extension will simply not run on the end-user's machine unless they manually install the package. Which of these options seems the best choice? Have I missed any pros and cons for each of the options?

  Read the article

• Cheese won't start

  - by Anthony Hohenheim

  I can't start Cheese Webcam Booth. It starts loading and there is a brief moment when the window shows up but then it disappears, like it shuts itself down and it's not in system monitor. My webcam works perfectly in Skype video call. I installed and run Camorama and it gave me an error: Could not connect to video device (/dev/video0) Please check connection When I run the lsusb I get this line for my webcam: Bus 002 Device 002: ID 04f2:b210 Chicony Electronics Co., Ltd And for my graphic card, running lspci: VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07) It's not a pressing matter, but it bugs my nerves, if it works on Skype, why does Cheese and other programs refuse to run. As I said, it's not a big deal but any help would be appreciated. Running Cheese in terminal: (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkImage to a GtkToggleButton, but as a GtkBin subclass a GtkToggleButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkImage to a GtkToggleButton, but as a GtkBin subclass a GtkToggleButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkImage to a GtkToggleButton, but as a GtkBin subclass a GtkToggleButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkHBox to a GtkButton, but as a GtkBin subclass a GtkButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkImage to a GtkButton, but as a GtkBin subclass a GtkButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkHBox to a GtkToggleButton, but as a GtkBin subclass a GtkToggleButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gtk-WARNING **: Attempting to add a widget with type GtkImage to a GtkButton, but as a GtkBin subclass a GtkButton can only contain one widget at a time; it already contains a widget of type GtkLabel (cheese:11454): Gdk-WARNING **: The program 'cheese' received an X Window System error. This probably reflects a bug in the program. The error was 'BadDrawable (invalid Pixmap or Window parameter)'. (Details: serial 932 error_code 9 request_code 137 minor_code 9) (Note to programmers: normally, X errors are reported asynchronously; that is, you will receive the error a while after causing it. To debug your program, run it with the --sync command line option to change this behavior. You can then get a meaningful backtrace from your debugger if you break on the gdk_x_error() function.)

  Read the article

• Ubuntu 12.04 x64 LTS VPN Server not changing IP

  - by user288778

  I used this guide http://silverlinux.blogspot.co.uk/2012/05/how-to-pptp-vpn-on-ubuntu-1204-pptpd.html and it worked fine. I'm able to connect but the problem is, that my IP being changed to "localip" not "remote ip". This is what I get from tail -f /var/log/syslog [code] June 6 00:09:19 instant5860 NetworkManager[1456]: Unmanaged Device found; state CONNECTED forced (see http://bugs.launchpad.net/bugs/191889) June 6 00:09:19 instant5860 NetworkManager[1456]: Marking connection 'Wired connection 1' invalid. June 6 00:09:19 instant5860 NetworkManager[1456]: Activation (eth1) failed. June 6 00:09:19 instant5860 NetworkManager[1456]: Activation (eth1) Stage 4 of 5 (IPv4 Configure Timeout) complete. June 6 00:09:19 instant5860 NetworkManager[1456]: (eth1): device state change: failed - disconnected (reason 'none') [120 30 0] June 6 00:09:19 instant5860 NetworkManager[1456]: (eth1): deactivating device (reason 'none') [0] June 6 00:09:19 instant5860 NetworkManager[1456]: Unmanaged Device found; state CONNECTED forced. June----- avahi-daemon[440]: Withdrawing address record for fe80......... on eth1 Jun------avahi-daemon[440]: Leaving mDNS multicast group on interface eth1. IPv6 with address fe80..... Jun------avahi-daemon[440]: Interface eth1.IPv6 no longer relevant for mDNS. Jun------avahi-daemon[440]: Joining mDNS multicast group on interface eth1.IPv6 with address fe80.... Jun------avahi-daemon[440]: New relevant interface eth1.IPv6 for mDNS Jun------avahi-daemon[440]: Registering new address record for fe80..... on eth1.*. Jun - snmpd[1172]: error on subcontainer 'ia_addr' insert (-1) dbusp382]: [syste] Activating service name='org.freedesktop.PackageKit' (using servicehelper) AptDaemon: INFO: Initializing daemon AptDaemon.PackageKit: INFO: Initializing PackageKit compat layer dbus[382]: [system] Successfu;;y activated service 'org.freedesktop.PackageKit' AptDaemon.PackageKit: INFO: Initializing PackageKit transaction AptDaemon.Worker: INFO: Simulating trans: /org/debian/apt/transaction/233beca013a0473ea34d9dea805af5df AptDaemon.Worker: INFO: Processing transaction /org/debian/apt... AptDaemon.PackageKit: INFO: Get updates() AptDaemon.Worker: INFO: Finished snmpd[1172]: error on subcontainer pptpd[23611]: CTRL: Client 82.33.... control connection started pptpd[23611]: CTRL: Starting call (launching pppd, opening GRE) pptpd[23611]: pppd 2.4.5 started by root uid 0 pptpd[23611]: Using interface ppp0 pptpd[23611]: Connect ppp0 <-- /dev/pts/1 NetworkManager[1456]: SCPlugin - Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0) NetworkManager[1456]:SCPlugin - Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found. pptpd[23612]: peer from calling number 82... authorized. kernel: [2918261.416923] init: ufw pre-start process (23613) terminated with status 1 dhclient: DHCPDISCOVER on eth1 to 255.255.255.255 port 67 interval 7 CTRL: Ignored a SET LING info packet with real ACCMs! local IP address:109.0.121.197 remote IP address: 109.0.84.56 dhclient: DHCPDISCOVER on eth1 to 255.255.255.255 port 67 interval 13 NetworkManager[1456]: (eth1): DHCPv4 request timed out. NetworkManager[1456]: (eth1): canceled DHCP transaction, DHCP client pid 23280 NetworkManager[1456]: Activation (eth1) Stage 4 of 5 (IPv4 Configure Timeout) scheduled... NetworkManager[1456]: Activation (eth1) Stage 4 of 5 (IPv4 Configure Timeout) started... NetworkManager[1456]: (eth1): device state change: ip-config - failed (reason 'ip-config-unavailable') [70 120 5[ NetworkManager[1456]: Unmanaged 'ia_addr' insert (-1)[/code]

  Read the article

• Software Architecture Analysis Method (SAAM)

  Software Architecture Analysis Method (SAAM) is a methodology used to determine how specific application quality attributes were achieved and how possible changes in the future will affect quality attributes based on hypothetical cases studies. Common quality attributes that can be utilized by this methodology include modifiability, robustness, portability, and extensibility. Quality Attribute: Application Modifiability The Modifiability quality attribute refers to how easy it changing the system in the future will be. This to me is a very open-ended attribute because a business could decide to transform a Point of Sale (POS) system in to a Lead Tracking system overnight. (Yes, this did actually happen to me) In order for SAAM to be properly applied for checking this attribute specific hypothetical case studies need to be created and review for the modifiability attribute due to the fact that various scenarios would return various results based on the amount of changes. In the case of the POS change out a payment gateway or adding an additional payment would have scored very high in comparison to changing the system over to a lead management system. I personally would evaluate this quality attribute based on the S.O.I.L.D Principles of software design. I have found from my experience the use of S.O.I.L.D in software design allows for the adoption of changes within a system. Quality Attribute: Application Robustness The Robustness quality attribute refers to how an application handles the unexpected. The unexpected can be defined but is not limited to anything not anticipated in the originating design of the system. For example: Bad Data, Limited to no network connectivity, invalid permissions, or any unexpected application exceptions. I would personally evaluate this quality attribute based on how the system handled the exceptions. Robustness Considerations Did the system stop or did it handle the unexpected error? Did the system log the unexpected error for future debugging? What message did the user receive about the error? Quality Attribute: Application Portability The Portability quality attribute refers to the ease of porting an application to run in a new operating system or device. For example, It is much easier to alter an ASP.net website to be accessible by a PC, Mac, IPhone, Android Phone, Mini PC, or Table in comparison to desktop application written in VB.net because a lot more work would be involved to get the desktop app to the point where it would be viable to port the application over to the various environments and devices. I would personally evaluate this quality attribute based on each new environment for which the hypothetical case study identifies. I would pay particular attention to the following items. Portability Considerations Hardware Dependencies Operating System Dependencies Data Source Dependencies Network Dependencies and Availabilities  Quality Attribute: Application Extensibility The Extensibility quality attribute refers to the ease of adding new features to an existing application without impacting existing functionality. I would personally evaluate this quality attribute based on each new environment for the following Extensibility  Considerations Hard coded Variables versus Configurable variables Application Documentation (External Documents and Codebase Documentation.) The use of Solid Design Principles

  Read the article

• Very basic OpenGL ES 2 error

  - by user16547

  This is an incredibly simple shader, yet I'm having a lot of trouble understanding what's wrong with it. I'm trying to send a float to my fragment shader. Its purpose is to adjust the alpha of the fragment colour. Here is my fragment shader: precision mediump float; uniform sampler2D u_Texture; uniform float u_Alpha; varying vec2 v_TexCoordinate; void main() { gl_FragColor = texture2D(u_Texture, v_TexCoordinate); gl_FragColor.a *= u_Alpha; } and below is my rendering method. I get a 1282 (invalid operation) on the GLES20.glUniform1f(u_Alpha, alpha); line. alpha is 1 (but I tried other values as well) and transparent is true: public void render() { GLES20.glUseProgram(mProgram); if(transparent) { GLES20.glEnable(GLES20.GL_BLEND); GLES20.glBlendFunc(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA); GLES20.glUniform1f(u_Alpha, alpha); } Matrix.setIdentityM(mModelMatrix, 0); Matrix.rotateM(mModelMatrix, 0, angle, 0, 0, 1); Matrix.translateM(mModelMatrix, 0, x, y, z); Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0); Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mMVPMatrix, 0); GLES20.glUniformMatrix4fv(u_MVPMatrix, 1, false, mMVPMatrix, 0); GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vbo[0]); GLES20.glVertexAttribPointer(a_Position, 3, GLES20.GL_FLOAT, false, 12, 0); GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, vbo[1]); GLES20.glVertexAttribPointer(a_TexCoordinate, 2, GLES20.GL_FLOAT, false, 8, 0); //snowTexture start GLES20.glActiveTexture(GLES20.GL_TEXTURE0); GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureHandle[0]); GLES20.glUniform1i(u_Texture, 0); GLES20.glBindBuffer(GLES20.GL_ELEMENT_ARRAY_BUFFER, ibo[0]); GLES20.glDrawElements(GLES20.GL_TRIANGLE_STRIP, indices.capacity(), GLES20.GL_UNSIGNED_BYTE, 0); GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0); GLES20.glBindBuffer(GLES20.GL_ELEMENT_ARRAY_BUFFER, 0); if(transparent) { GLES20.glDisable(GLES20.GL_BLEND); } GLES20.glUseProgram(0); }

  Read the article

• Our own Daily WTF

  - by Dennis Vroegop

  Originally posted on: http://geekswithblogs.net/dvroegop/archive/2014/08/20/our-own-daily-wtf.aspxIf you're a developer, you've probably heard of the website the DailyWTF. If you haven't, head on over to http://www.thedailywtf.com and read. And laugh. I'll wait. Read it? Good. If you're a bit like me probably you've been wondering how on earth some people ever get hired as a software engineer. Most of the stories there seem to weird to be true: no developer would write software like that right? And then you run into a little nugget of code one of your co-workers wrote. And then you realize: "Hey, it happens everywhere!" Look at this piece of art I found in our codebase recently: public static decimal ToDecimal(this string input) {     System.Globalization.CultureInfo cultureInfo = System.Globalization.CultureInfo.InstalledUICulture;     var numberFormatInfo = (System.Globalization.NumberFormatInfo)cultureInfo.NumberFormat.Clone();     int dotIndex = input.IndexOf(".");     int commaIndex = input.IndexOf(",");     if (dotIndex > commaIndex)         numberFormatInfo.NumberDecimalSeparator = ".";     else if (commaIndex > dotIndex)         numberFormatInfo.NumberDecimalSeparator = ",";     decimal result;     if (decimal.TryParse(input, System.Globalization.NumberStyles.Float, numberFormatInfo, out result))         return result;     else         throw new Exception(string.Format("Invalid input for decimal parsing: {0}. Decimal separator: {1}.", input, numberFormatInfo.NumberDecimalSeparator)); }  Me and a collegue have been looking long and hard at this and what we concluded was the following: Apparently, we don't trust our users to be able to correctly set the culture in Windows. Users aren't able to determine if they should tell Windows to use a decimal point or a comma to display numbers. So what we've done here is make sure that whatever the user enters, we'll translate that into whatever the user WANTS to enter instead of what he actually did. So if you set your locale to US, since you're a US citizen, but you want to enter the number 12.34 in the Dutch style (because, you know, the Dutch are way cooler with numbers) so you enter 12,34 we will understand this and respect your wishes! Of course, if you change your mind and in the next input field you decide to use the decimal dot again, that's fine with us as well. We will do the hard work. Now, I am all for smart software. Software that can handle all sorts of input the user can think of. But this feels a little uhm, I don't know.. wrong.. Or am I too old fashioned?

  Read the article

• Reasons to Use a VM For Development

  - by George Stocker

  Background: I work at a start-up company, where one team uses Virtual Machines to connect to a remote server to do their development, and another team (the team I'm on) uses local IIS/SQL Server 2005/Visual Studio installations to conduct work. Team VM is located about 1000 miles from Team Non-VM, and the servers the VMs run off of are located near Team VM (Latency, for those that are wondering, is about 50ms). A person high in the company is pushing for Team Non-VM to use virtual machines for programming, development, and testing. The latter point we agree on -- we want Virtual Machines to test configurations and various aspects of the web application in a 'clean' state. The Problem: What we don't agree on is having developers using RDP to connect to a desktop remotely that contains Visual Studio, SQL Server, and IIS to do the same development we could do locally on our laptops. I've tried the VM set-up, and besides the color issue, there is a latency issue that is rather noticeable, not to mention that since we're a start-up, a good number of employees work from home on occasion with our work laptops, and this move would cut off the laptops. They'd be turned in. Reasons to Use Remote VMs for Development (Not Testing!): Here are the stated reasons that this person wants us to use VMs: They work for TeamVM. They keep the source code "safe". If we want to work from home, we could just use our home PCs. Licenses (I don't know what the argument is, only that it's been used). Reasons not to use Remote VMs for Development: Here are the stated reasons why we don't want to use VMs: We like working from home. We get a lot done on our own time. We're not going to use our Home PCs to do work related stuff. The Latency is noticeable. Support for the VMs (if they go down, or if we need a new VM) takes a while. We don't have administrative privileges on the VM, and are unable to change settings as needed. What I'm looking for from the community is this: What reasons would you give for not using VMs for development? Keep in mind these are remote VMs -- this isn't a VM running on a local desktop. It's using the laptop (or a desktop) as a thin client for a remote VM. Also, on the other side of the coin: Is there something we're missing that makes VMs more palatable for development? Edit: I think 'safe' is used in term of corporate espionage, or more correctly if the Laptop gets stolen, the person who stole would have access to our source code. The former (as we've pointed out, is always going to be a possibility -- companies stop that with litigation, there isn't a technical solution (so far as I can see)). The latter point is ( though I don't know its usefulness in a corporate scenario) mitigated by Truecrypt'ing the entire volume.

  Read the article

• How to specialize a c++ variadic template?

  - by Serge

  I'm trying to understand c++ variadic templates. I'm not much aware of the correct language to use to explain what I'd like to achieve, so it might be simpler if I provide a bit of code which illustrate what I'd like to achieve. #include <iostream> #include <string> using namespace std; template<int ...A> class TestTemplate1 { public: string getString() { return "Normal"; } }; template<int T, int ...A> string TestTemplate1<2, A...>::getString() { return "Specialized"; } template<typename ...A> class TestTemplate2 { }; int main() { TestTemplate1<1, 2, 3, 4> t1_1; TestTemplate1<1, 2> t1_2; TestTemplate1<> t1_3; TestTemplate1<2> t1_4; TestTemplate2<> t2_1; TestTemplate2<int, double> t2_2; cout << t1_1.getString() << endl; cout << t1_2.getString() << endl; cout << t1_3.getString() << endl; cout << t1_4.getString() << endl; } This throws several errors. error C2333: 'TestTemplate1<::getString' : error in function declaration; skipping function body error C2333: 'TestTemplate1<1,2,3,4::getString' : error in function declaration; skipping function body error C2333: 'TestTemplate1<1,2::getString' : error in function declaration; skipping function body error C2333: 'TestTemplate1<2::getString' : error in function declaration; skipping function body error C2977: 'TestTemplate1' : too many template arguments error C2995: 'std::string TestTemplate1::getString(void)' : function template has already been defined error C3860: template argument list following class template name must list parameters in the order used in template parameter list How can I have a specialized behavior for every TestTemplate1<2, ...> instances like t1_4?

  Read the article

• Are closures with side-effects considered "functional style"?

  - by Giorgio

  Many modern programming languages support some concept of closure, i.e. of a piece of code (a block or a function) that Can be treated as a value, and therefore stored in a variable, passed around to different parts of the code, be defined in one part of a program and invoked in a totally different part of the same program. Can capture variables from the context in which it is defined, and access them when it is later invoked (possibly in a totally different context). Here is an example of a closure written in Scala: def filterList(xs: List[Int], lowerBound: Int): List[Int] = xs.filter(x => x >= lowerBound) The function literal x => x >= lowerBound contains the free variable lowerBound, which is closed (bound) by the argument of the function filterList that has the same name. The closure is passed to the library method filter, which can invoke it repeatedly as a normal function. I have been reading a lot of questions and answers on this site and, as far as I understand, the term closure is often automatically associated with functional programming and functional programming style. The definition of function programming on wikipedia reads: In computer science, functional programming is a programming paradigm that treats computation as the evaluation of mathematical functions and avoids state and mutable data. It emphasizes the application of functions, in contrast to the imperative programming style, which emphasizes changes in state. and further on [...] in functional code, the output value of a function depends only on the arguments that are input to the function [...]. Eliminating side effects can make it much easier to understand and predict the behavior of a program, which is one of the key motivations for the development of functional programming. On the other hand, many closure constructs provided by programming languages allow a closure to capture non-local variables and change them when the closure is invoked, thus producing a side effect on the environment in which they were defined. In this case, closures implement the first idea of functional programming (functions are first-class entities that can be moved around like other values) but neglect the second idea (avoiding side-effects). Is this use of closures with side effects considered functional style or are closures considered a more general construct that can be used both for a functional and a non-functional programming style? Is there any literature on this topic? IMPORTANT NOTE I am not questioning the usefulness of side-effects or of having closures with side effects. Also, I am not interested in a discussion about the advantages / disadvantages of closures with or without side effects. I am only interested to know if using such closures is still considered functional style by the proponent of functional programming or if, on the contrary, their use is discouraged when using a functional style.

  Read the article

• Why can't I install Microsoft Office 2007 in Ubuntu 11.04?

  - by DK new

  I am very new to Ubuntu and only just getting a hang of it, and my questions might sound stupid especially because I am a learner in terms of techie things as well. So because of the nature of work where everyone uses stupid Windows and Microsoft, I need to have access to MS Office 2007/2010 as documents with too many tables or images open all haywire in Libre Office (which has otherwise been great!). I have been reading up about installing MS Office through WINE/PlayonLinux, but have been unsuccessful so far. I downloaded a MS Office 2007 package from Pirate Bay, which I extracted into a folder. I tried numerous different ways to install through WINE and PlayonLinux, but will discuss the one which seems to be getting me somewhere. http://www.webupd8.org/2011/01/how-to-install-microsoft-office-2007-in.html ..... Initially, when I would click on the install button of MS Office, I get a message saying "The install location you selected does not have 1558MB free space. Free up space from the selected install location or choose a different install location". The install location in this case said "C:\Program Files\Microsoft Office", which confused me as I don't have drives named as C, Z etc. I went to configure WINE and under the drives tab, created a drive named A with the path location /media/cd025f16-433b-4a90-abb6-bb7a025d0450/. Also the space thing is confusing as I have at least 450GB of unused space on my computer. anyways, when I selected the A drive for installation, the installation starts, but soon I get the following error message, "Office cannot find Office.en-us\OfficeLR.Cab. Browse to a valid installation source" .... The part saying "OfficeLR.Cab" have said different things after the Office bit every time I have made an attempt. When I select the Office.en-us sub-folder or any other folder within the folder where MS Office 2007 is saved, it says "invalid source"! I have been trying to get this sorted since 15hrs now (addictive!) and have learnt loads of things in the process, but have not managed to crack it. It might be something stupidly simple I am not aware off that is stopping it. I would really appreciate some help! Thanks a lot.. Also I am still getting used to the language, so might have many questions Also I am using Ubuntu 11.04 (tag 11.04). Also I think I don't have windows -- when my friend installed Ubuntu on my new laptop which had Windows 7, he was trying to keep windows in a separate partition, but something happened and windows was not there! Looking forward to some support! Again thanks a lot

  Read the article

< Previous Page | 215 216 217 218 219 220 221 222 223 224 225 226  | Next Page >