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  • keyup bindings not working in Firefox

    - by Jarred
    Hi. You can see my project here - http://www.inluxphoto.com/custom/jsgallery/index.php I am attempting to make the left and right arrow keys move the slideshow. I was able to get it to work in all browsers by following exactly the instructions on the front page of jqueryfordesigners.com (sorry I am only allowed one link). However, it is necessary that the keyup be unbinded until the animation completes, so the user cannot do a quick double tap of the key, which breaks the show. This led me to the following function - function keyCommands() { //Bind Keys according to keyAssignments function keyCommandBind() { $(document.documentElement).bind('keyup', keyAssignments) } //Bind functions to specific keys function keyAssignments() { if (event.keyCode == 37) { leftArrow(); } if (event.keyCode == 39) { rightArrow(); } if (event.keyCode == 32) { spaceBar(); } } function leftArrow() { //unbind, do stuff, rebind } function rightArrow() { //unbind, do stuff, rebind } function spaceBar() { //unbind, do stuff, rebind } keyCommandBind(); } This works in all browsers except Firefox & Camino. Firebug tells me event (ie event.keyCode) is not defined. That's true, it's not defined, and I understand that. However I don't understand why, if it's not defined, does it work in all other browsers. How can I appropriately define this? Or, am I doing it wrong? Any help would be most appreciated, thanks for your time!

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  • WPF: Selecting the Target of an Animation

    - by Phil Sandler
    I am trying to create a simple (I think) animation effect based on a property change in my ViewModel. I would like the target to be a specific textblock in the control template of a custom control, which inherits from Window. From the article examples I've seen, a DataTrigger is the easiest way to accomplish this. It appears that Window.Triggers doesn't support DataTriggers, which led me to try to apply the trigger in the style. The problem I am currently having is that I can't seem to target the TextBlock (or any other child control)--what happens is which the code below is that the animation is applied to the background of the whole window. If I leave off StoryBoard.Target completely, the effect is exactly the same. Is this the right approach with the wrong syntax, or is there an easier way to accomplish this? <Style x:Key="MyWindowStyle" TargetType="{x:Type Window}"> <Setter Property="Template" Value="{StaticResource MyWindowTemplate}"/> <Style.Triggers> <DataTrigger Binding="{Binding ChangeOccurred}" Value="True"> <DataTrigger.EnterActions> <BeginStoryboard> <Storyboard BeginTime="00:00:00" Duration="0:0:2" Storyboard.Target="{Binding RelativeSource={RelativeSource AncestorType=TextBlock}}" Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"> <ColorAnimation FillBehavior="Stop" From="Black" To="Red" Duration="0:0:0.5" AutoReverse="True"/> </Storyboard> </BeginStoryboard> </DataTrigger.EnterActions> </DataTrigger> </Style.Triggers> </Style>

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  • python histogram one-liner

    - by mykhal
    there are many ways, how to code histogram in Python. by histogram, i mean function, counting objects in an interable, resulting in the count table (i.e. dict). e.g.: >>> L = 'abracadabra' >>> histogram(L) {'a': 5, 'b': 2, 'c': 1, 'd': 1, 'r': 2} it can be written like this: def histogram(L): d = {} for x in L: if x in d: d[x] += 1 else: d[x] = 1 return d ..however, there are much less ways, how do this in a single expression. if we had "dict comprehensions" in python, we would write: >>> { x: L.count(x) for x in set(L) } but we don't have them, so we have to write: >>> dict([(x, L.count(x)) for x in set(L)]) however, this approach may yet be readable, but is not efficient - L is walked-through multiple times, so this won't work for single-life generators.. the function should iterate well also through gen(), where: def gen(): for x in L: yield x we can go with reduce (R.I.P.): >>> reduce(lambda d,x: dict(d, x=d.get(x,0)+1), L, {}) # wrong! oops, does not work, the key name is 'x', not x :( i ended with: >>> reduce(lambda d,x: dict(d.items() + [(x, d.get(x, 0)+1)]), L, {}) (in py3k, we would have to write list(d.items()) instead of d.items(), but it's hypothethical, since there is no reduce there) please beat me with a better one-liner, more readable! ;)

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  • IE problem: keyboard interaction with checkbox

    - by Bobby Eickhoff
    I have an HTML table, and each row has a checkbox for selecting or deselecting its row. Whenever a checkbox changes value, I need to add or remove highlighting to the row and also ensure that the page's submit button is only enabled when at least one row is selected and disabled otherwise. The checkbox event handler is defined by the following function: function getCheckboxCallback() { return function () { var parentRow = getParentRow(this); if (!parentRow) { return; // No parent row found; abort } // Adjust the appearance of the row setSelected(parentRow, this.checked); // Count the number of selected table rows, and disable the submit // button whenever no rows are selected enforceInvariants(); return true; }; } Elsewhere in the same module, the checkboxes are given the event handlers: checkbox.onchange = getCheckboxCallback(); checkbox.onclick = getCheckboxCallback(); // alleged IE fix I'm working in Windows XP, and everything works fine in both Firefox 3 and Opera 9. However, IE 7 does not handle keyboard interaction well (mouse interaction works fine). The problem is that if a checkbox has the focus and I hit the spacebar, the checkbox doesn't get checked -- instead it gets half checked (it has the same shadowed appearance that it would get immediately after a mousedown). I have to press the spacebar a second time to actually check the box. Similarly, it requires two key presses to uncheck it. Oddly enough, if I hold down the spacebar for a few moments, then a single press works as expected. Can anyone explain what is going on here? Is there something I'm doing wrong in the JavaScript code that is causing this behavior? How can I fix this?

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  • Excel CSV into Nested Dictionary; List Comprehensions

    - by victorhooi
    heya, I have a Excel CSV files with employee records in them. Something like this: mail,first_name,surname,employee_id,manager_id,telephone_number [email protected],john,smith,503422,503423,+65(2)3423-2433 [email protected],george,brown,503097,503098,+65(2)3423-9782 .... I'm using DictReader to put this into a nested dictionary: import csv gd_extract = csv.DictReader(open('filename 20100331 original.csv'), dialect='excel') employees = dict([(row['employee_id'], row) for row in gp_extract]) Is the above the proper way to do it - it does work, but is it the Right Way? Something more efficient? Also, the funny thing is, in IDLE, if I try to print out "employees" at the shell, it seems to cause IDLE to crash (there's approximately 1051 rows). 2. Remove employee_id from inner dict The second issue issue, I'm putting it into a dictionary indexed by employee_id, with the value as a nested dictionary of all the values - however, employee_id is also a key:value inside the nested dictionary, which is a bit redundant? Is there any way to exclude it from the inner dictionary? 3. Manipulate data in comprehension Thirdly, we need do some manipulations to the imported data - for example, all the phone numbers are in the wrong format, so we need to do some regex there. Also, we need to convert manager_id to an actual manager's name, and their email address. Most managers are in the same file, while others are in an external_contractors CSV, which is similar but not quite the same format - I can import that to a separate dict though. Are these two items things that can be done within the single list comprehension, or should I use a for loop? Or does multiple comprehensions work? (sample code would be really awesome here). Or is there a smarter way in Python do it? Cheers, Victor

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  • PHPUnit - multiple stubs of same class

    - by keithjgrant
    I'm building unit tests for class Foo, and I'm fairly new to unit testing. A key component of my class is an instance of BarCollection which contains a number of Bar objects. One method in Foo iterates through the collection and calls a couple methods on each Bar object in the collection. I want to use stub objects to generate a series of responses for my test class. How do I make the Bar stub class return different values as I iterate? I'm trying to do something along these lines: $stubs = array(); foreach ($array as $value) { $barStub->expects($this->any()) ->method('GetValue')) ->will($this->returnValue($value)); $stubs[] = $barStub; } // populate stubs into `Foo` // assert results from `Foo->someMethod()` So Foo->someMethod() will produce data based on the results it receives from the Bar objects. But this gives me the following error whenever the array is longer than one: There was 1 failure: 1) testMyTest(FooTest) with data set #2 (array(0.5, 0.5)) Expectation failed for method name is equal to <string:GetValue> when invoked zero or more times. Mocked method does not exist. /usr/share/php/PHPUnit/Framework/MockObject/Mock.php(193) : eval()'d code:25 One thought I had was to use ->will($this->returnCallback()) to invoke a callback method, but I don't know how to indicate to the callback which Bar object is making the call (and consequently what response to give). Another idea is to use the onConsecutiveCalls() method, or something like it, to tell my stub to return 1 the first time, 2 the second time, etc, but I'm not sure exactly how to do this. I'm also concerned that if my class ever does anything other than ordered iteration on the collection, I won't have a way to test it.

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  • How to get rid of the GUI access from shared library.

    - by Inso Reiges
    Hello, In my project i have a shared library with cross-platform code that provides a very convenient abstraction for a number of its clients. To be more specific, this library provides data access to encrypted files generated by main application on a number of platforms. There is a great deal of complicated code there that implements cryptographic protocols and as such is very error-prone and should be shared as much as possible across clients and platforms. However parsing all this encrypted stuff requires asking user for a number of different secrets ones in a while. The secret can be either a password, a number of shared passwords or a public key file and this list is a hot target for extension in the future. I can't really ask the user for any of those secrets beforehand from main application, because i really don't know what i need to ask for until i start working with the encrypted data directly in the library code. So i will have to create dialogs and call them from the library code. However i really see this as a bad idea, because (among other things) there is a possibility of a windows service using it and services can't have GUI access. The question is, are there any known ways or patterns to get rid of the GUI calls that are suitable for my case? Thank you.

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  • SQL Server Blocking Issue

    - by Robin Weston
    We currently have an issue that occurs roughly once a day on SQL 2005 database server, although the time it happens is not consistent. Basically, the database grinds to a halt, and starts refusing connections with the following error message. This includes logging into SSMS: A connection was successfully established with the server, but then an error occurred during the login process. (provider: TCP Provider, error: 0 - The specified network name is no longer available.) Our CPU usage for SQL is usually around 15%, but when the DB is in it's broken state it's around 70%, so it's clearly doing something, even if no-one can connect. Even if I disable the web app that uses the database the CPU still doesn't go down. I am unable to restart the SQLSERVER process as it is unresponsive, so I have to end up killing the process manually, which then puts the DB into Suspect/Recovery mode (which I can fix but it's a pain). Below are some PerfMon stats I gathered when the DB was in it's broken state which might help. I have a bunch more if people want to request them: Active Transactions: 2 (Never Changes) Logical Connections: 34 (NC) Process Blocked: 16 (NC) User Connections: 30 (NC) Batch Request: 0 (NC) Active Jobs: 2 (NC) Log Truncations: 596 (NC) Log Shrinks: 24 (NC) Longest Running Transaction Time: 99 (NC) I guess they key is finding out what the DB is using it's CPU on, but as I can't even log into SSMS this isn't possible with the standard methods. Disturbingly, I can't even use the dedicated admin connection to get into SSMS. I get the same timout as with all other requests. Any advice, reccomendations, or even sympathy, is much appreciated!

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  • Why doesn't the F# Set implement ISet<T>?

    - by Sean Devlin
    The .NET Framework is adding an ISet<T> interface with the 4.0 release. In the same release, F# is being added as a first-class language. F# provides an immutable Set<'T> class. It would seem logical to me that the immutable set provided would implement the ISet<T> interface, but it doesn't. Does anyone know why? My guess is that they didn't want to implement an interface intended to be mutable, but I don't think this explanation holds up. After all, their Map<'Key, 'Value> class implements IDictionary, which is mutable. And there are examples elsewhere in the framework of classes implementing interfaces that are only partially appropriate. My other thought is that ISet<T> is new, so maybe they didn't get around to it. But that seems kind of thin. Does the fact that ISet<T> is generic (v. IDictionary, which is not) have anything to do with it? Any thoughts on the matter would be appreciated.

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  • WPF In-Memory Image Display

    - by Aren B
    Im trying to build an Item Template for my list-view and im bound to a list of Entities. The entity I have has a System.Drawing.Image that I'd like to display, but so far I cannot for the life of me figure out how to bind it to the <Image> block. Every example and documentation I can find on the internet pertains to Images accessible via an uri i.e. File on HDD or On Website <DataTemplate x:Key="LogoPreviewItem"> <Border BorderBrush="Black" BorderThickness="1"> <DockPanel Width="150" Height="100"> <Image> <Image.Source> <!-- {Binding PreviewImage} is where the System.Drawing.Image is in this context --> </Image.Source> </Image> <Label DockPanel.Dock="Bottom" Content="{Binding CustomerName}" /> </DockPanel> </Border> </DataTemplate>

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  • Free tools/libraries to compare tables with filtering in different databases and visualize/sync diff

    - by MicMit
    I am building certain GUI in C# for a content manager and looking for the tools or code snippets or open libraries ( code ideally in C# ) which allow me the following : 1. For table A in database X (test ) and table A in database Y (production) and for a simple filter ( e.g. listname = "XYZ" ) I need to show additions/deletions/updates in some way. which might be side-by-side or just html report 2 record added html table with some fields 2 record deleted html table with some fields Considering that this task is very common, I guess, certain components should exist ? Components either return some collections from parameters given for further visualizing or just produce reports mentioned above. 2. I need to push changes for the filter I mentioned in 1 and update table in production database for this filter only ( ie for the particular list approved by content person). Again probably there are certain SQL code generators - components in addition to diffs or standalone. 3. The key thing tools/libraries - should be suitable for integration with the existing application in C#.

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  • Encryption puzzle / How to create a ProxyStub for a Remote Assistance ticket

    - by Jon Clegg
    I am trying to create a ticket for Remote Assistance. Part of that requires creating a PassStub parameter. As of the documenation: http://msdn.microsoft.com/en-us/library/cc240115(PROT.10).aspx PassStub: The encrypted novice computer's password string. When the Remote Assistance Connection String is sent as a file over e-mail, to provide additional security, a password is used.<16 In part 16 they detail how to create as PassStub. In Windows XP and Windows Server 2003, when a password is used, it is encrypted using PROV_RSA_FULL predefined Cryptographic provider with MD5 hashing and CALG_RC4, the RC4 stream encryption algorithm. As PassStub looks like this in the file: PassStub="LK#6Lh*gCmNDpj" If you want to generate one yourself run msra.exe in Vista or run the Remote Assistance tool in WinXP. The documentation says this stub is the result of the function CryptEncrypt with the key derived from the password and encrypted with the session id (Those are also in the ticket file). The problem is that CryptEncrypt produces a binary output way larger then the 15 byte PassStub. Also the PassStub isn't encoding in any way I've seen before. Some interesting things about the PassStub encoding. After doing statistical analysis the 3rd char is always a one of: !#$&()+-=@^. Only symbols seen everywhere are: *_ . Otherwise the valid characters are 0-9 a-z A-Z. There are a total of 75 valid characters and they are always 15 bytes. Running msra.exe with the same password always generates a different PassStub, indicating that it is not a direct hash but includes the rasessionid as they say. Some other ideas I've had is that it is not the direct result of CryptEncrypt, but a result of the rasessionid in the MD5 hash. In MS-RA (http://msdn.microsoft.com/en-us/library/cc240013(PROT.10).aspx). The "PassStub Novice" is simply hex encoded, and looks to be the right length. The problem is I have no idea how to go from any hash to way the ProxyStub looks like.

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  • mEncrypt/Decrypt binary mp3 with mcrypt, missing mimetype

    - by Jeremy Dicaire
    I have a script that read a mp3 file and encrypt it, I want to be able to decrypt this file and convert it to base64 so it can play in html5. Key 1 will be stored on the page and static, key2 will be unique for each file, for testing I used: $key1 = md5(time()); $key2 = md5($key1.time()); Here is my encode php code : //Get file content $file = file_get_contents('test.mp3'); //Encrypt file $Encrypt = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key1, $file, MCRYPT_MODE_CBC, $key2); $Encrypt = trim(base64_encode($Encrypt)); //Create new file $fileE = "test.mp3e"; $fileE = fopen($file64, 'w') or die("can't open file"); //Put crypted content fwrite($fileE, $Encrypt); //Close file fclose($fileE); Here is the code that doesnt work (decoded file is same size, but no mimetype): //Get file content $fileE = file_get_contents('test.mp3e'); //Decode $fileDecoded = base64_decode($fileE); //Decrypt file $Decrypt = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key1, $fileDecoded, MCRYPT_MODE_CBC, $key2); $Decrypt = trim($Decrypt); //Create new file $file = "test.mp3"; $file = fopen($file, 'w') or die("can't open file"); //Put crypted content fwrite($file, $Decrypt); //Close file fclose($file);

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  • Capturing time intervals when somebody was online? How would you impement this feature?

    - by Kirzilla
    Hello, Our aim is to build timelines saying about periods of time when user was online. (It really doesn't matter what user we are talking about and where he was online) To get information about onliners we can call API method, someservice.com/api/?call=whoIsOnline whoIsOnline method will give us a list of users currently online. But there is no API method to get information about who IS NOT online. So, we should build our timelines using information we got from whoIsOnline. Of course there will be a measurement error (we can't track information in realtime). Let's suppose that we will call whoIsOnline method every 2 minutes (yes, we will run our script by cron every 2 minutes). For example, calling whoIsOnline at 08:00 will return Peter_id Michal_id Andy_id calling whoIsOnline at 08:02 will return Michael_id Andy_id George_id As you can see, Peter has gone offline, but we have new onliner - George. Available instruments are Db(MySQL) / text files / key-value storage (Redis/memcache); feel free to choose any of them (or even all of them). So, we have to get information like this George_id was online... 12 May: 08:02-08:30, 12:40-12:46, 20:14-22:36 11 May: 09:10-12:30, 21:45-23:00 10 May: was not online And now question... How would you store information to implement such timelines? How would you query/calculate information about periods of time when user was online? Additional information.. You cannot update information about offline users, only users who are "currently" online. Solution should be flexible: timeline information could be represented relating to any timezone. We should keep information only for last 7 days. Every user seen online is automatically getting his own identifier in our database. Uff.. it was really hard for me to write it because my English is pretty bad, but I hope my question will be clear for you. Thank you.

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  • LINQ query code for complex merging of data.

    - by Stacey
    I've posted this before, but I worded it poorly. I'm trying again with a more well thought out structure. Re-writing this a bit to make it more clear. I have the following code and I am trying to figure out the shorter linq expression to do it 'inline'. Please examine the "Run()" method near the bottom. I am attempting to understand how to join two dictionaries together based on a matching identifier in one of the objects - so that I can use the query in this sort of syntax. var selected = from a in items.List() // etc. etc. select a; This is my class structure. The Run() method is what I am trying to simplify. I basically need to do this conversion inline in a couple of places, and I wanted to simplify it a great deal so that I can define it more 'cleanly'. class TModel { public Guid Id { get; set; } } class TModels : List<TModel> { } class TValue { } class TStorage { public Dictionary<Guid, TValue> Items { get; set; } } class TArranged { public Dictionary<TModel, TValue> Items { get; set; } } static class Repository { static public TItem Single<TItem, TCollection>(Predicate<TItem> expression) { return default(TItem); // access logic. } } class Sample { public void Run() { TStorage tStorage = new TStorage(); // access tStorage logic here. Dictionary<TModel, TValue> d = new Dictionary<TModel, TValue>(); foreach (KeyValuePair<Guid, TValue> kv in tStorage.Items) { d.Add(Repository.Single<TModel, TModels>(m => m.Id == kv.Key),kv.Value); } } }

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  • How to change the view angle and label value of a chart .NET C#

    - by George
    Short Description I am using charts for a specific application where i need to change the view angle of the rendered 3D Pie chart and value of automatic labels from pie label names to corresponding pie values. This how the chart looks: Initialization This is how i initialize it: Dictionary<string, decimal> secondPersonsWithValues = HistoryModel.getSecondPersonWithValues(); decimal[] yValues = new decimal[secondPersonsWithValues.Values.Count]; //VALUES string[] xValues = new string[secondPersonsWithValues.Keys.Count]; //LABELS secondPersonsWithValues.Keys.CopyTo(xValues, 0); secondPersonsWithValues.Values.CopyTo(yValues, 0); incomeExpenseChart.Series["Default"].ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Pie; incomeExpenseChart.Series["Default"].Points.DataBindXY(xValues, yValues); incomeExpenseChart.ChartAreas["Default"].Area3DStyle.Enable3D = true; incomeExpenseChart.Series["Default"].CustomProperties = "PieLabelStyle=Outside"; incomeExpenseChart.Legends["Default"].Enabled = true; incomeExpenseChart.ChartAreas["Default"].Area3DStyle.LightStyle = System.Windows.Forms.DataVisualization.Charting.LightStyle.Realistic; incomeExpenseChart.Series["Default"]["PieDrawingStyle"] = "SoftEdge"; Basically i am querying data from database using the HistoryModel.getSecondPersonWithValues(); to get pairs as Dictionary<string, decimal> where key is the person and value is ammount. Problem #1 What i need is to be able to change the marked labels from person names to the ammounts or add another label of ammounts with the same colors (See Image). Problem #2 Another problem is that i need to change the view angle of 3D Pie chart. Maybe it's very simple and I just don't know the needed property or maybe i need to override some paint event. Either ways any kind of ways would be appriciated. Thanks in advance George.

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  • Ruby - encrypted_strings

    - by Tom Andersen
    A bit of a Ruby newbie here - should be an easy question: I want to use the encrypted_strings gem to create a password encrypted string: (from http://rdoc.info/projects/pluginaweek/encrypted_strings) Question is: Everything works fine, but how come I don't need the password to decrypt the string? Say I want to store the string somewhere for a while,like the session. Is the password also stored with it? (which would seem very strange?). And no, I'm not planning on using 'secret-key' or any similar hack as a password. I am planning on dynamically generating a class variable @@password using a uuid, which I don't store other than in memory, and can change from one running of the program to the next. Symmetric: >> password = 'shhhh' => "shhhh" >> crypted_password = password.encrypt(:symmetric, :password => 'secret_key') => "qSg8vOo6QfU=\n" >> crypted_password.class => String >> crypted_password == 'shhhh' => true >> password = crypted_password.decrypt => "shhhh"

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  • Free tools/libraries to compare tables with filtering for SQL Server 2008 and visualize/sync diffs t

    - by MicMit
    I am building certain GUI in C# for a content manager and looking for the tools or code snippets or open libraries ( code ideally in C# ) which allow me the following : 1. For table A in database X (test ) and table A in database Y (production) and for a simple filter ( e.g. listname = "XYZ" ) I need to show additions/deletions/updates in some way. which might be side-by-side or just html report 2 record added html table with some fields 2 record deleted html table with some fields Considering that this task is very common, I guess, certain components should exist ? Components either return some collections from parameters given for further visualizing or just produce reports mentioned above. 2. I need to push changes for the filter I mentioned in 1 and update table in production database for this filter only ( ie for the particular list approved by content person). Again probably there are certain SQL code generators - components in addition to diffs or standalone. 3. The key thing tools/libraries - should be suitable for integration with the existing application in C#.

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  • Flex 3: should I provide prepared data to my component or make it to process data before display?

    - by grapkulec
    I'm starting to learn a little Flex just for fun and maybe to prove that I still can learn something new :) I have some idea for a project and one of its parts is a tree component which could display data in different ways depending on configuration. The idea There is list of objects having properties like id, date, time, name, description. And sometimes list should be displayed like this: first level: date second level: time third level: name and sometimes like this: first level: year second level: month third level: day fourth level: time and name By level I mean level of nesting of course. So, we can have years, that have months, that have days, that have hours and so forth. The problem What could be the best way to do it? I mean, should I prepare data for different ways of nesting outside of component or even outside of flex? I can do it at web service level in C# where I plan to have database access layer and send to flex nice and ready to display XML or array of objects. But I wonder if that won't cause additional and maybe unneccessary network traffic. I tried to hack some code in my component to convert my data objects into XML or ArrayCollection but I don't know enough of Flex and got stuck on elimination of duplicates or getting specific data by some key value. Usually to do such things I have STL with maps, sets and vectors and I find Flex arrays and even Dictionary a little bit confusing (I've read language reference and googled without any significant luck). The question So, to sum things up: should I give my tree component data prepared just for chosen type of display or should I try to do it internally inside component (or some helper class written in ActionScript)?

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  • How to inherit from a non-prototype object

    - by Andres Jaan Tack
    The node-binary binary parser builds its object with the following pattern: exports.parse = function parse (buffer) { var self = {...} self.tap = function (cb) {...}; self.into = function (key, cb) {...}; ... return self; }; How do I inherit my own, enlightened parser from this? Is this pattern designed intentionally to make inheritance awkward? My only successful attempt thus far at inheriting all the methods of binary.parse(<something>) is to use _.extend as: var clever_parser = function(buffer) { if (this instanceof clever_parser) { this.parser = binary.parse(buffer); // I guess this is super.constructor(...) _.extend(this.parser, this); // Really? return this.parser; } else { return new clever_parser(buffer); } } This has failed my smell test, and that of others. Is there anything about this that makes in tangerous?

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  • Python halts while iteratively processing my 1GB csv file

    - by Dan
    I have two files: metadata.csv: contains an ID, followed by vendor name, a filename, etc hashes.csv: contains an ID, followed by a hash The ID is essentially a foreign key of sorts, relating file metadata to its hash. I wrote this script to quickly extract out all hashes associated with a particular vendor. It craps out before it finishes processing hashes.csv stored_ids = [] # this file is about 1 MB entries = csv.reader(open(options.entries, "rb")) for row in entries: # row[2] is the vendor if row[2] == options.vendor: # row[0] is the ID stored_ids.append(row[0]) # this file is 1 GB hashes = open(options.hashes, "rb") # I iteratively read the file here, # just in case the csv module doesn't do this. for line in hashes: # not sure if stored_ids contains strings or ints here... # this probably isn't the problem though if line.split(",")[0] in stored_ids: # if its one of the IDs we're looking for, print the file and hash to STDOUT print "%s,%s" % (line.split(",")[2], line.split(",")[4]) hashes.close() This script gets about 2000 entries through hashes.csv before it halts. What am I doing wrong? I thought I was processing it line by line. ps. the csv files are the popular HashKeeper format and the files I am parsing are the NSRL hash sets. http://www.nsrl.nist.gov/Downloads.htm#converter UPDATE: working solution below. Thanks everyone who commented! entries = csv.reader(open(options.entries, "rb")) stored_ids = dict((row[0],1) for row in entries if row[2] == options.vendor) hashes = csv.reader(open(options.hashes, "rb")) matches = dict((row[2], row[4]) for row in hashes if row[0] in stored_ids) for k, v in matches.iteritems(): print "%s,%s" % (k, v)

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  • Why put a DAO layer over a persistence layer (like JDO or Hibernate)

    - by Todd Owen
    Data Access Objects (DAOs) are a common design pattern, and recommended by Sun. But the earliest examples of Java DAOs interacted directly with relational databases -- they were, in essence, doing object-relational mapping (ORM). Nowadays, I see DAOs on top of mature ORM frameworks like JDO and Hibernate, and I wonder if that is really a good idea. I am developing a web service using JDO as the persistence layer, and am considering whether or not to introduce DAOs. I foresee a problem when dealing with a particular class which contains a map of other objects: public class Book { // Book description in various languages, indexed by ISO language codes private Map<String,BookDescription> descriptions; } JDO is clever enough to map this to a foreign key constraint between the "BOOKS" and "BOOKDESCRIPTIONS" tables. It transparently loads the BookDescription objects (using lazy loading, I believe), and persists them when the Book object is persisted. If I was to introduce a "data access layer" and write a class like BookDao, and encapsulate all the JDO code within this, then wouldn't this JDO's transparent loading of the child objects be circumventing the data access layer? For consistency, shouldn't all the BookDescription objects be loaded and persisted via some BookDescriptionDao object (or BookDao.loadDescription method)? Yet refactoring in that way would make manipulating the model needlessly complicated. So my question is, what's wrong with calling JDO (or Hibernate, or whatever ORM you fancy) directly in the business layer? Its syntax is already quite concise, and it is datastore-agnostic. What is the advantage, if any, of encapsulating it in Data Access Objects?

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  • WPF Collapsed Grid not Styling

    - by Eric
    So, I have a grid inside a listbox. The purpose is that when the listboxitem is selected, I want the grid to show, having the selected item expand to show more detail information. I set up a style trigger for this and it works great, except for one thing: the labels and textblocks styles are unapplied on the grid. I'm assuming this has something to do with the default state of the listboxitem being collapsed, so wpf skips the styles, I was hoping it would put them on when selected fired, but it doesn't. If I use Style="{StaticResource Mystyle}" on each label/textblock, it styles fine, it just seems to not be doing the inherited style magic like it does with visible grids elsewhere in the app. See code below, the labels don't show up bolded or anything when the grid appears. <Style TargetType="{x:Type Grid}" x:Key="ListBoxItemCollapseGrid"> <Style.Triggers> <DataTrigger Binding="{Binding Path=IsSelected, RelativeSource= { RelativeSource Mode=FindAncestor, AncestorType={x:Type ListBoxItem} } }" Value="False"> <Setter Property="Grid.Visibility" Value="Collapsed" /> </DataTrigger> </Style.Triggers> <Style.Resources> <Style TargetType="{x:Type Label}"> <Setter Property="FontWeight" Value="Bold" /> <Setter Property="Foreground" Value="{StaticResource BaseText}" /> <Setter Property="Padding" Value="3,0,0,0" /> </Style> <Style TargetType="{x:Type TextBlock}"> <Setter Property="Foreground" Value="{StaticResource BaseText}" /> </Style> </Style.Resources> </Style>

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  • Creating a class Hierarchy for Atoms,neutrons,protons,chemical reationc

    - by Smart Zulu
    I need help to create a program that can show the hierarchy of any Atoms and its components (neutrons,protons,electrons,and chemical reaction) Here is a code of what i have done so far,being a novice at the subject using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Atoms { public class Atoms { protected string name = "Sodium"; protected string element ="Metal"; public virtual void GetInfo() { Console.WriteLine("name: {0}",name); Console.WriteLine("element: {0}", element); } } class Proton : Atoms { public int number = 11 ; public override void GetInfo() { base.GetInfo(); Console.WriteLine("Proton number: {0}",number); } } class Electron : Atoms { public int number = 11; public override void GetInfo() { base.GetInfo(); Console.WriteLine("Electron number: {0}", number); } class Neutrons : Atoms { public int number = 12; public override void GetInfo() { base.GetInfo(); Console.WriteLine("Neutron number: {0}", number); } class TestClass { static void Main() { Proton P = new Proton(); P.GetInfo(); Neutrons N = new Neutrons(); N.GetInfo(); Electron E = new Electron(); E.GetInfo(); Console.WriteLine("click any key to exit"); Console.ReadLine(); } } } } }

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  • mySQL Efficiency Issue - How to find the right balance of normalization...?

    - by Foo
    I'm fairly new to working with relational databases, but have read a few books and know the basics of good design. I'm facing a design decision, and I'm not sure how to continue. Here's a very over simplified version of what I'm building: People can rate photos 1-5, and I need to display the average votes on the picture while keeping track of the individual votes. For example, 12 people voted 1, 7 people voted 2, etc. etc. The normalization freak of me initially designed the table structure like this: Table pictures id* | picture | userID | Table ratings id* | pictureID | userID | rating With all the foreign key constraints and everything set as they shoudl be. Every time someone rates a picture, I just insert a new record into ratings and be done with it. To find the average rating of a picture, I'd just run something like this: SELECT AVG(rating) FROM ratings WHERE pictureID = '5' GROUP by pictureID Having it setup this way lets me run my fancy statistics to. I can easily find who rated a certain picture a 3, and what not. Now I'm thinking if there's a crapload of ratings (which is very possible in what I'm really designing), finding the average will became very expensive and painful. Using a non-normalized version would seem to be more efficient. e.g.: Table picture id | picture | userID | ratingOne | ratingTwo | ratingThree | ratingFour | ratingFive To calculate the average, I'd just have to select a single row. It seems so much more efficient, but so much more uglier. Can someone point me in the right direction of what to do? My initial research shows that I have to "find the right balance", but how do I go about finding that balance? Any articles or additional reading information would be appreciated as well. Thanks.

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