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  • xubuntu keyboard application shortcuts not working

    - by Guanidene
    I am using the latest Xubuntu 13.04 with Xfce 4.10. I have issues while setting "Application Shortucts' from 'Settings Manager Keyboard Application Shortcuts'. Not all custom keyboards shortcuts, which I have added, work. Some do, some don't. Example the command 'xdotool key XF86AudioPause' works perfect from cmdline, but not when I assign this as a shortcut to some key, say 'F11'. Have tried to Google about this, but found nothing. Kindly help. If possible, kindly provide me a cmdline way to set a keyboard shortcut

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  • How do I edit keyboard preferences from the command line?

    - by jumpnett
    I want to swap the Caps Lock and Escape key as specified in this answer: Use the keyboard preferences to swap Caps Lock and Escape - seriously, how often do you use Caps Lock? Using vim you will be using Escape all the time, and having it available on the home row makes a huge difference. With the standard Ubuntu desktop, go through the menus: System - Preferences - Keyboard - Layouts tab. Then hit the "Layout Options" button, click on the triangle next to "Caps Lock key behaviour" and select "Swap ESC and CapsLock". but, I'm using Ubuntu Server with no gui, so how would I do this from the command line?

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  • Classless tables possible with Datamapper?

    - by barerd
    I have an Item class with the following attributes: itemId,name,weight,volume,price,required_skills,required_items. Since the last two attributes are going to be multivalued, I removed them and create new schemes like: itemID,required_skill (itemID is foreign key, itemID and required_skill is primary key.) Now, I'm confused how to create/use this new table. Here are the options that came to my mind: 1) The relationship between Items and Required_skills is one-to-many, so I may create a RequiredSkill class, which belongs_to Item, which in turn has n RequiredSkills. Then I can do Item.get(1).requiredskills. This sounds most logical to me. 2) Since required_skills may well be thought of as constants (since they resemble rules), I may put them into a hash or gdbm database or another sql table and query from there, which I don't prefer. My question is: is there sth like a modelless table in datamapper, where datamapper is responsible from the creation and integrity of the table and allows me to query it in datamapper way, but does not require a class, like I may do it in sql?

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  • What's the best way to cache a growing database table for html generation?

    - by McLeopold
    I've got a database table which will grow in size by about 5000 rows a hour. For a key that I would be querying by, the query will grow in size by about 1 row every hour. I would like a web page to show the latest rows for a key, 50 at a time (this is configurable). I would like to try and implement memcache to keep database activity low for reads. If I run a query and create a cache result for each page of 50 results, that would work until a new entry is added. At that time, the page of latest results gets new result and the oldest results drops off. This cascades down the list of cached pages causing me to update every cache result. It seems like a poor design. I could build the cache pages backwards, then for each page requested I should get the latest 2 pages and truncate to the proper length of 50. I'm not sure if this is good or bad? Ideally, the mechanism I use to insert a new row would also know how to invalidate the proper cache results. Has someone already solved this problem in a widely acceptable way? What's the best method of doing this? EDIT: If my understanding of the MYSQL query cache is correct, it has table level granularity in invalidation. Given the fact that I have about 5000 updates before a query on a key should need to be invalidated, it seems that the database query cache would not be used. MS SQL caches execution plans and frequently accessed data pages, so it may do better in this scenario. My query is not against a single table with TOP N. One version has joins to several tables and another has sub-selects. Also, since I want to cache the html generated table, I'm wondering if a cache at the web server level would be appropriate? Is there really no benefit to any type of caching? Is the best advice really to just allow a website site query to go through all the layers and hit the database every request?

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  • How to set up an rsync backup to Ubuntu securely?

    - by ws_e_c421
    I have been following various other tutorials and blog posts on setting up a Ubuntu machine as a backup "server" (I'll call it a server, but it's just running Ubuntu desktop) that I push new files to with rsync. Right now, I am able to connect to the server from my laptop using rsync and ssh with an RSA key that I created and no password prompt when my laptop is connected to my home router that the server is also connected to. I would like to be able to send files from my laptop when I am away from home. Some of the tutorials I have looked at had some brief suggestions about security, but they didn't focus on them. What do I need to do to let my laptop with send files to the server without making it too easy for someone else to hack into the server? Here is what I have done so far: Ran ssh-keygen and ssh-copy-id to create a key pair for my laptop and server. Created a script on the server to write its public ip address to a file, encrypt the file, and upload to an ftp server I have access to (I know I could sign up for a free dynamic DNS account for this part, but since I have the ftp account and don't really need to make the ip publicly accessible I thought this might be better). Here are the things I have seen suggested: Port forwarding: I know I need to assign the server a fixed ip address on the router and then tell the router to forward a port or ports to it. Should I just use port 22 or choose a random port and use that? Turn on the firewall (ufw). Will this do anything, or will my router already block everything except the port I want? Run fail2ban. Are all of those things worth doing? Should I do anything else? Could I set up the server to allow connections with the RSA key only (and not with a password), or will fail2ban provide enough protection against malicious connection attempts? Is it possible to limit the kinds of connections the server allows (e.g. only ssh)? I hope this isn't too many questions. I am pretty new to Ubuntu (but use the shell and bash scripts on OSX). I don't need to have the absolute most secure set up. I'd like something that is reasonably secure without being so complicated that it could easily break in a way that would be hard for me to fix.

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  • Adopt a Java EE 7 JSR!

    - by reza_rahman
    Broad community participation is key to the success of any technology worth it's salt. The Adopt-a-JSR program was launched in recognition of this fact. It is an initiative by some key JUG leaders around the World to encourage JUG members to get involved in a JSR and to evangelize that JSR to their JUG and the wider Java community, in order to increase grass roots participation. There are a number of JUGs that have already jumped in like the Chennai JUG, SouJava, London Java Community, BeJUG, GoJava, Morrocco JUG, Campinas JUG and ItpJava. Note that any developer can participate, there isn't a need to be a JUG leader. There are a number of Java EE 7 JSRs that could use your help right now including WebSocket, JSON, Caching, Concurrency for EE, JAX-RS2 and JMS2. Find out more here.

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  • Help with ubuntu 11 mis-displays

    - by Alfa9Dev
    So, I sea This tutorial, and I exectued this line in my terminal : sudo add-apt-repository ppa:lubuntu-desktop/ppa & sudo apt-get install lubuntu-desktop and my left-side panel changed abit, while the Dash Home changed to become like so : http://i43.tinypic.com/2vuc0lj.png ! help ! How can I change to the ubuntu default style or ppa ! because whene I run this : sudo add-apt-repository ppa:ubuntu-desktop/ppa it gives me the follwing notice : gpg: requesting key A1231595 from hkp server keyserver.ubuntu.com gpg: key A1231595: "Launchpad PPA for Ubuntu Desktop" not changed gpg: Total number processed: 1 gpg: unchanged: 1 does this mean that the ubuntu ppa isn't changed or what ?? Please, help any help would very appreciated :)

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  • How do you assign commands to keys to in Terminal?

    - by NES
    Is there a solution to assign special key combinations to words in terminal use. For example the less command is very usefull and i use i a lot to pipe the output of another process through it. The idea would be to set up special key combinations that are only active in terminal use assigned to write different commands? So pressing CTRL + l in terminal window could write | less or CTRL + G could stand for | grep Note: i just mean adding the letters to commandline not execute the finally. A similar way what's tabcompletion but more specific.

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  • Authentication error when trying to upgrade from 11.10 to 12.04

    - by mahmuodmasri
    I wrote : ~$ do-release-upgrade and the system says: Checking for a new ubuntu release Get:1 Upgrade tool signature [198 B] Get:2 Upgrade tool [1551 kB] Fetched 1551 kB in 6s (167 kB/s) extracting 'precise.tar.gz' authenticate 'precise.tar.gz' against 'precise.tar.gz.gpg' exception from gpg: GnuPG exited non-zero, with code 2 Debug information: gpg: Signature made Thu 11 Oct 2012 07:47:10 AM EET using DSA key ID 437D05B5 gpg: can't open `/etc/apt/trusted.gpg' gpg: keydb_search failed: file open error gpg: Can't check signature: public key not found Authentication failed Authenticating the upgrade failed. There may be a problem with the network or with the server. Please help me!

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  • JOB OF THE WEEK

    - by Maria Sandu
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} My name is Pascaline and I am the EMEA Solution Response Manager. I currently have a role open for a Benelux Solution Response Representative to jump-start his/her career in my international team of six people from all across Europe. Key for this exciting role is that you are curious to learn, like networking and constantly want to develop yourself. To help you with that, you will get extensive product trainings and workshops on all Oracle product lines and you will receive sales training. Further, you have the opportunity to get certified on Oracle products through online trainings and workshops. Every month you will also benefit from 1-on-1 sales coaching and regular coaching from me to help you grow and develop your career at Oracle! The role will include the follow-up of marketing events and online marketing activities with current Key Accounts in the Benelux. It is truly a pioneering role at Oracle as it is the first time that an employee will engage in business conversations about all lines of businesses and products ranges with Key Accounts. So are you interested to work in between marketing and sales? Do you want to work for a big IT multinational? Do you want to work abroad after you graduate and do you want to develop yourself? Then please visit this link for more information.

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  • Code for Controlling the Bike in a bike game

    - by user1489257
    I'm new(ish) to Actionscript 3 and I was wondering what the code what would be like for controlling the bike in a game. I have a two main questions: Is Box2D the best physics engine to go with for this type of game? How would the animation of the bike work. Would I have to create a bike animation of the wheels moving and make it start and stop when the key to go forward is pressed. How would I go about it slowly stopping when the key to go forward is released? Thanks.

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  • Syanptics Touchpad Won't Re-enable

    - by user71607
    I disabled my Synaptics touchpad while a key on my keyboard and now I can't get it to work again. When I press that key again it says the touchpad turns back on but will not work at all. Rebooting doesn't help, and I tried installing touchpad-indicator but when I try to enable from there it says that it enables, but the icon remains like it's disabled. The odd thing is that it works on the lock screen so I know the drivers aren't messed up, it's just a setting. Also, the touchpad works on guest mode but still nothing on my account. I tried using gconf to set the touchpad_enable to true and it worked, it sure set it. Doesn't make a difference though, my touchpad is still useless. Terminal commands I've used: gconftool-2 --set --type boolean /desktop/gnome/peripherals/touchpad/touchpad_enabled true synclient Touchpadoff=0 modprobe psmouse

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  • Unable to stop TOSHIBA TransMemory

    - by user66498
    I have a USB,when I choose safety remove, occur this error message.How to solve the problem? Unable to stop TOSHIBA TransMemory Error detaching: helper exited with exit code 1: Detaching device /dev/sdb USB device: /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.2) SYNCHRONIZE CACHE: synchronize cache(10): Fixed format, current; Sense key: Key=9 Additional sense: Logical unit not ready, cause not reportable Info fld=0x0 [0] FAILED: No such file or directory (Continuing despite SYNCHRONIZE CACHE failure.) STOP UNIT: start stop unit: transport: Host_status=0x07 [DID_ERROR] Driver_status=0x00 [DRIVER_OK, SUGGEST_OK] FAILED: No such file or directory

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  • Does home directory encryption depend on gnome keyring?

    - by pedorro
    My gnome-keyring has somehow gotten messed up. It prompts for a password (that I know I never provided - yes I chose 'unsafe storage'). None of the possible passwords that I use (including empty) are working. So basically I want to delete the default key so I can start over. I just want to confirm that this isn't somehow tied to my home directory encryption. I want to be sure that if I delete the default key from it, I will still be able to log in normally and decrypt my home directory. It seems likely that they're unrelated as the keyring is within the home directory and is thus itself encrypted, but I just thought I'd ask. Anyone have any thoughts?

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  • Is it good practice to keep 2 related tables (using auto_increment PK) to have the same Max of auto_increment ID when table1 got modified?

    - by Tum
    This question is about good design practice in programming. Let see this example, we have 2 interrelated tables: Table1 textID - text 1 - love.. 2 - men... ... Table2 rID - textID 1 - 1 2 - 2 ... Note: In Table1: textID is auto_increment primary key In Table2: rID is auto_increment primary key & textID is foreign key The relationship is that 1 rID will have 1 and only 1 textID but 1 textID can have a few rID. So, when table1 got modification then table2 should be updated accordingly. Ok, here is a fictitious example. You build a very complicated system. When you modify 1 record in table1, you need to keep track of the related record in table2. To keep track, you can do like this: Option 1: When you modify a record in table1, you will try to modify a related record in table 2. This could be quite hard in term of programming expecially for a very very complicated system. Option 2: instead of modifying a related record in table2, you decided to delete old record in table 2 & insert new one. This is easier for you to program. For example, suppose you are using option2, then when you modify record 1,2,3,....,100 in table1, the table2 will look like this: Table2 rID - textID 101 - 1 102 - 2 ... 200 - 100 This means the Max of auto_increment IDs in table1 is still the same (100) but the Max of auto_increment IDs in table2 already reached 200. what if the user modify many times? if they do then the table2 may run out of records? we can use BigInt but that make the app run slower? Note: If you spend time to program to modify records in table2 when table1 got modified then it will be very hard & thus it will be error prone. But if you just clear the old record & insert new records into table2 then it is much easy to program & thus your program is simpler & less error prone. So, is it good practice to keep 2 related tables (using auto_increment PK) to have the same Max of auto_increment ID when table1 got modified?

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  • event table in php [closed]

    - by user66403
    How to create php code for fetch the time and date by using id from database two tables have to create named event & event_time --1. table name event(1. event_id, 2.event_date) these are the 2 fields & this(event_id) is primary key --2. table name event_time(1.event_id(foreign key) 2.event_sub_id 3.event_time) these are the 3 fields. if we give date it should display time from 12am to 12pm (24hrs) if anyone knows please post the answer immediately its very urgent please please please...

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  • RSA Encrypt / Decrypt Problem in .NET

    - by Brendon Randall
    I'm having a problem with C# encrypting and decrypting using RSA. I have developed a web service that will be sent sensitive financial information and transactions. What I would like to be able to do is on the client side, Encrypt the certain fields using the clients RSA Private key, once it has reached my service it will decrypt with the clients public key. At the moment I keep getting a "The data to be decrypted exceeds the maximum for this modulus of 128 bytes." exception. I have not dealt much with C# RSA cryptography so any help would be greatly appreciated. This is the method i am using to generate the keys private void buttonGenerate_Click(object sender, EventArgs e) { string secretKey = RandomString(12, true); CspParameters param = new CspParameters(); param.Flags = CspProviderFlags.UseMachineKeyStore; SecureString secureString = new SecureString(); byte[] stringBytes = Encoding.ASCII.GetBytes(secretKey); for (int i = 0; i < stringBytes.Length; i++) { secureString.AppendChar((char)stringBytes[i]); } secureString.MakeReadOnly(); param.KeyPassword = secureString; RSACryptoServiceProvider rsaProvider = new RSACryptoServiceProvider(param); rsaProvider = (RSACryptoServiceProvider)RSACryptoServiceProvider.Create(); rsaProvider.KeySize = 1024; string publicKey = rsaProvider.ToXmlString(false); string privateKey = rsaProvider.ToXmlString(true); Repository.RSA_XML_PRIVATE_KEY = privateKey; Repository.RSA_XML_PUBLIC_KEY = publicKey; textBoxRsaPrivate.Text = Repository.RSA_XML_PRIVATE_KEY; textBoxRsaPublic.Text = Repository.RSA_XML_PUBLIC_KEY; MessageBox.Show("Please note, when generating keys you must sign on to the gateway\n" + " to exhange keys otherwise transactions will fail", "Key Exchange", MessageBoxButtons.OK, MessageBoxIcon.Information); } Once i have generated the keys, i send the public key to the web service which stores it as an XML file. Now i decided to test this so here is my method to encrypt a string public static string RsaEncrypt(string dataToEncrypt) { string rsaPrivate = RSA_XML_PRIVATE_KEY; CspParameters csp = new CspParameters(); csp.Flags = CspProviderFlags.UseMachineKeyStore; RSACryptoServiceProvider provider = new RSACryptoServiceProvider(csp); provider.FromXmlString(rsaPrivate); ASCIIEncoding enc = new ASCIIEncoding(); int numOfChars = enc.GetByteCount(dataToEncrypt); byte[] tempArray = enc.GetBytes(dataToEncrypt); byte[] result = provider.Encrypt(tempArray, true); string resultString = Convert.ToBase64String(result); Console.WriteLine("Encrypted : " + resultString); return resultString; } I do get what seems to be an encrypted value. In the test crypto web method that i created, i then take this encrypted data, try and decrypt the data using the clients public key and send this back in the clear. But this is where the exception is thrown. Here is my method responsible for this. public string DecryptRSA(string data, string merchantId) { string clearData = null; try { CspParameters param = new CspParameters(); param.Flags = CspProviderFlags.UseMachineKeyStore; RSACryptoServiceProvider rsaProvider = new RSACryptoServiceProvider(param); string merchantRsaPublic = GetXmlRsaKey(merchantId); rsaProvider.FromXmlString(merchantRsaPublic); byte[] asciiString = Encoding.ASCII.GetBytes(data); byte[] decryptedData = rsaProvider.Decrypt(asciiString, false); clearData = Convert.ToString(decryptedData); } catch (CryptographicException ex) { Log.Error("A cryptographic error occured trying to decrypt a value for " + merchantId, ex); } return clearData; } If anyone could help me that would be awesome, as i have said i have not done much with C# RSA encryption/decryption.

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  • Where to Store the Protection Trial Info for Software Protection Purpose

    - by Peter Lee
    It might be duplicate with other questions, but I swear that I googled a lot and search at StackOverflow.com a lot, and I cannot find the answer to my question: In a C#.Net application, where to store the protection trial info, such as Expiration Date, Number of Used Times? I understand that, all kinds of Software Protection strategies can be cracked by a sophiscated hacker (because they can almost always get around the expiration checking step). But what I'm now going to do is just to protect it in a reasonable manner that a "common"/"advanced" user cannot screw it up. OK, in order to proof that I have googled and searched a lot at StackOverflow.com, I'm listing all the possible strategies I got: 1. Registry Entry First, some users might not have the access to even read the Registry table. Second, if we put the Protection Trial Info in a Registry Entry, the user can always find it out where it is by comparing the differences before and after the software installation. They can just simply change it. OK, you might say that we should encrypt the Protection Trial Info, yes we can do that. But what if the user just change their system date before installing? OK, you might say that we should also put a last-used date, if something is wrong, the last-used date could work as a protection guide. But what if the user just uninstall the software and delete all Registry Entries related to this software, and then reinstall the software? I have no idea on how to deal with this. Please help. A Plain File First, there are some places to put the plain file: 2.a) a simple XML file under software installation path 2.b) configuration file Again, the user can just uninstall the software and remove these plain file(s), and reinstall the software. - The Software Itself If we put the protection trial info (Expiration Date, we cannot put Number of Used Times) in the software itself, it is still susceptible to the cases I mentioned above. Furthermore, it's not even cool to do so. - A Trial Product-Key It works like a licensing process, that is, we put the Trial info into an RSA-signed string. However, it requires too many steps for a user to have a try of using the software (they might lose patience): 4.a) The user downloads the software; 4.b) The user sends an email to request a Trial Product-Key by providing user name (or email) or hardware info; 4.c) The server receives the request, RSA-signs it and send back to the user; 4.d) The user can now use it under the condition of (Expiration Date & Number of Used Times). Now, the server has a record of the user's username or hardware info, so the user will be rejected to request a second trial. Is it legal to collection hardware info? In a word, the user has to do one more extra step (request a Trial Product Key) just for having a try of using the software, which is not cool (thinking myself as a user). NOTE: This question is not about the Licensing, instead, it's about where to store the TRIAL info. After the trial expires, the user should ask for a license (CD-Key/Product-Key). I'm going to use RSA signature (bound to User Hardware)

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  • Running multiple image manipulations in parallel causing OutOfMemory exception

    - by Tom
    I am working on a site where I need to be able to split and image around 4000x6000 into 4 parts (amongst many other tasks) and I need this to be as quick as possible for multiple users. My current code for doing this is var bitmaps = new RenderTargetBitmap[elements.Length]; using (var stream = blobService.Stream(key)) { BitmapImage bi = new BitmapImage(); bi.BeginInit(); bi.StreamSource = stream; bi.EndInit(); for (var i = 0; i < elements.Length; i++) { var element = elements[i]; TransformGroup transformGroup = new TransformGroup(); TranslateTransform translateTransform = new TranslateTransform(); translateTransform.X = -element.Left; translateTransform.Y = -element.Top; transformGroup.Children.Add(translateTransform); DrawingVisual vis = new DrawingVisual(); DrawingContext cont = vis.RenderOpen(); cont.PushTransform(transformGroup); cont.DrawImage(bi, new Rect(new Size(bi.PixelWidth, bi.PixelHeight))); cont.Close(); RenderTargetBitmap rtb = new RenderTargetBitmap(element.Width, element.Height, 96d, 96d, PixelFormats.Default); rtb.Render(vis); bitmaps[i] = rtb; } } for (var i = 0; i < bitmaps.Length; i++) { using (MemoryStream ms = new MemoryStream()) { PngBitmapEncoder encoder = new PngBitmapEncoder(); encoder.Frames.Add(BitmapFrame.Create(bitmaps[i])); encoder.Save(ms); var regionKey = WebPath.Variant(key, elements[i].Id); saveBlobService.Save("image/png", regionKey, ms); } } I am running multiple threads which take jobs off a queue. I am finding that if this part of code is hit by 4 threads at once I get an OutOfMemory exception. I can stop this happening by wrapping all the code above in a lock(obj) but this isn't ideal. I have tried wrapping just the first using block (where the file is read from disk and split) but I still get the out of memory exceptions (this part of the code executes quite quickly). I this normal considering the amount of memory this should be taking up? Are there any optimisations I could make? Can I increase the memory available? UPDATE: My new code as per Moozhe's help public static void GenerateRegions(this IBlobService blobService, string key, Element[] elements) { using (var stream = blobService.Stream(key)) { foreach (var element in elements) { stream.Position = 0; BitmapImage bi = new BitmapImage(); bi.BeginInit(); bi.SourceRect = new Int32Rect(element.Left, element.Top, element.Width, element.Height); bi.StreamSource = stream; bi.EndInit(); DrawingVisual vis = new DrawingVisual(); DrawingContext cont = vis.RenderOpen(); cont.DrawImage(bi, new Rect(new Size(element.Width, element.Height))); cont.Close(); RenderTargetBitmap rtb = new RenderTargetBitmap(element.Width, element.Height, 96d, 96d, PixelFormats.Default); rtb.Render(vis); using (MemoryStream ms = new MemoryStream()) { PngBitmapEncoder encoder = new PngBitmapEncoder(); encoder.Frames.Add(BitmapFrame.Create(rtb)); encoder.Save(ms); var regionKey = WebPath.Variant(key, element.Id); blobService.Save("image/png", regionKey, ms); } } } }

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  • Can't access a map member from a pointer

    - by fjfnaranjo
    Hi. That's my first question :) I'm storing the configuration of my program in a Group->Key->Value form, like the old INIs. I'm storing the information in a pair of structures. First one, I'm using a std::map with string+ptr for the groups info (the group name in the string key). The second std::map value is a pointer to the sencond structure, a std::list of std::maps, with the finish Key->Value pairs. The Key-Value pairs structure is created dynamically, so the config structure is: std::map< std::string , std::list< std::map<std::string,std::string> >* > lv1; Well, I'm trying to implement two methods to check the existence of data in the internal config. The first one, check the existence of a group in the structure: bool isConfigLv1(std::string); bool ConfigManager::isConfigLv1(std::string s) { return !(lv1.find(s)==lv1.end()); } The second method, is making me crazy... It check the existence for a key inside a group. bool isConfigLv2(std::string,std::string); bool ConfigManager::isConfigLv2(std::string s,std::string d) { if(!isConfigLv1(s)) return false; std::map< std::string , std::list< std::map<std::string,std::string> >* >::iterator it; std::list< std::map<std::string,std::string> >* keyValue; std::list< std::map<std::string,std::string> >::iterator keyValueIt; it = lv1.find(s); keyValue = (*it).second; for ( keyValueIt = keyValue->begin() ; keyValueIt != keyValue->end() ; keyValueIt++ ) if(!((*keyValueIt).second.find(d)==(*keyValueIt).second.end())) return true; return false; } I don't understand what is wrong. The compiler says: ConfigManager.cpp||In member function ‘bool ConfigManager::isConfigLv2(std::string, std::string)’:| ConfigManager.cpp|(line over return true)|error: ‘class std::map<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >’ has no member named ‘second’| But it has to have the second member, because it's a map iterator... Any suggestion about what's happening? Sorry for my English :P, and consider I'm doing it as a exercise, I know there are a lot of cool configuration managers.

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  • Python TEA implementation

    - by Gaks
    Anybody knows proper python implementation of TEA (Tiny Encryption Algorithm)? I tried the one I've found here: http://sysadminco.com/code/python-tea/ - but it does not seem to work properly. It returns different results than other implementations in C or Java. I guess it's caused by completely different data types in python (or no data types in fact). Here's the code and an example: def encipher(v, k): y=v[0];z=v[1];sum=0;delta=0x9E3779B9;n=32 w=[0,0] while(n>0): y += (z << 4 ^ z >> 5) + z ^ sum + k[sum & 3] y &= 4294967295L # maxsize of 32-bit integer sum += delta z += (y << 4 ^ y >> 5) + y ^ sum + k[sum>>11 & 3] z &= 4294967295L n -= 1 w[0]=y; w[1]=z return w def decipher(v, k): y=v[0] z=v[1] sum=0xC6EF3720 delta=0x9E3779B9 n=32 w=[0,0] # sum = delta<<5, in general sum = delta * n while(n>0): z -= (y << 4 ^ y >> 5) + y ^ sum + k[sum>>11 & 3] z &= 4294967295L sum -= delta y -= (z << 4 ^ z >> 5) + z ^ sum + k[sum&3] y &= 4294967295L n -= 1 w[0]=y; w[1]=z return w Python example: >>> import tea >>> key = [0xbe168aa1, 0x16c498a3, 0x5e87b018, 0x56de7805] >>> v = [0xe15034c8, 0x260fd6d5] >>> res = tea.encipher(v, key) >>> "%X %X" % (res[0], res[1]) **'70D16811 F935148F'** C example: #include <unistd.h> #include <stdio.h> void encipher(unsigned long *const v,unsigned long *const w, const unsigned long *const k) { register unsigned long y=v[0],z=v[1],sum=0,delta=0x9E3779B9, a=k[0],b=k[1],c=k[2],d=k[3],n=32; while(n-->0) { sum += delta; y += (z << 4)+a ^ z+sum ^ (z >> 5)+b; z += (y << 4)+c ^ y+sum ^ (y >> 5)+d; } w[0]=y; w[1]=z; } int main() { unsigned long v[] = {0xe15034c8, 0x260fd6d5}; unsigned long key[] = {0xbe168aa1, 0x16c498a3, 0x5e87b018, 0x56de7805}; unsigned long res[2]; encipher(v, res, key); printf("%X %X\n", res[0], res[1]); return 0; } $ ./tea **D6942D68 6F87870D** Please note, that both examples were run with the same input data (v and key), but results were different. I'm pretty sure C implementation is correct - it comes from a site referenced by wikipedia (I couldn't post a link to it because I don't have enough reputation points yet - some antispam thing)

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  • python: what are efficient techniques to deal with deeply nested data in a flexible manner?

    - by AlexandreS
    My question is not about a specific code snippet but more general, so please bear with me: How should I organize the data I'm analyzing, and which tools should I use to manage it? I'm using python and numpy to analyse data. Because the python documentation indicates that dictionaries are very optimized in python, and also due to the fact that the data itself is very structured, I stored it in a deeply nested dictionary. Here is a skeleton of the dictionary: the position in the hierarchy defines the nature of the element, and each new line defines the contents of a key in the precedent level: [AS091209M02] [AS091209M01] [AS090901M06] ... [100113] [100211] [100128] [100121] [R16] [R17] [R03] [R15] [R05] [R04] [R07] ... [1263399103] ... [ImageSize] [FilePath] [Trials] [Depth] [Frames] [Responses] ... [N01] [N04] ... [Sequential] [Randomized] [Ch1] [Ch2] Edit: To explain a bit better my data set: [individual] ex: [AS091209M02] [imaging session (date string)] ex: [100113] [Region imaged] ex: [R16] [timestamp of file] ex [1263399103] [properties of file] ex: [Responses] [regions of interest in image ] ex [N01] [format of data] ex [Sequential] [channel of acquisition: this key indexes an array of values] ex [Ch1] The type of operations I perform is for instance to compute properties of the arrays (listed under Ch1, Ch2), pick up arrays to make a new collection, for instance analyze responses of N01 from region 16 (R16) of a given individual at different time points, etc. This structure works well for me and is very fast, as promised. I can analyze the full data set pretty quickly (and the dictionary is far too small to fill up my computer's ram : half a gig). My problem comes from the cumbersome manner in which I need to program the operations of the dictionary. I often have stretches of code that go like this: for mk in dic.keys(): for rgk in dic[mk].keys(): for nk in dic[mk][rgk].keys(): for ik in dic[mk][rgk][nk].keys(): for ek in dic[mk][rgk][nk][ik].keys(): #do something which is ugly, cumbersome, non reusable, and brittle (need to recode it for any variant of the dictionary). I tried using recursive functions, but apart from the simplest applications, I ran into some very nasty bugs and bizarre behaviors that caused a big waste of time (it does not help that I don't manage to debug with pdb in ipython when I'm dealing with deeply nested recursive functions). In the end the only recursive function I use regularly is the following: def dicExplorer(dic, depth = -1, stp = 0): '''prints the hierarchy of a dictionary. if depth not specified, will explore all the dictionary ''' if depth - stp == 0: return try : list_keys = dic.keys() except AttributeError: return stp += 1 for key in list_keys: else: print '+%s> [\'%s\']' %(stp * '---', key) dicExplorer(dic[key], depth, stp) I know I'm doing this wrong, because my code is long, noodly and non-reusable. I need to either use better techniques to flexibly manipulate the dictionaries, or to put the data in some database format (sqlite?). My problem is that since I'm (badly) self-taught in regards to programming, I lack practical experience and background knowledge to appreciate the options available. I'm ready to learn new tools (SQL, object oriented programming), whatever it takes to get the job done, but I am reluctant to invest my time and efforts into something that will be a dead end for my needs. So what are your suggestions to tackle this issue, and be able to code my tools in a more brief, flexible and re-usable manner?

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