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  • find contiguous stretches of equal data in a vector

    - by mariotomo
    I have a numeric vector, it contains patches of elements that are repeating, something like: R> data <- c(1,1,1,2,2,2,3,3,2,2,2,2,2,3,3,1,1,1,1,1) R> data [1] 1 1 1 2 2 2 3 3 2 2 2 2 2 3 3 1 1 1 1 1 R> I need to extract contiguous patches of elements equals to a specific value... but I'm only interested in the patch around a specific position. so, my input is: (1) the numeric vector, (2) the desired value, (3) the position. I want to return a logic vector indicating which positions satisfy the request. if at that position the data does not equal the value, I return all FALSE. possible outcomes that are not all F would be: [1] 1 1 1 2 2 2 3 3 2 2 2 2 2 3 3 1 1 1 1 1 [1] T T T F F F F F F F F F F F F F F F F F [2] F F F T T T F F F F F F F F F F F F F F [3] F F F F F F T T F F F F F F F F F F F F [4] F F F F F F F F T T T T T F F F F F F F [5] F F F F F F F F F F F F F T T F F F F F [6] F F F F F F F F F F F F F F F T T T T T

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  • How to find an embedded platform?

    - by gmagana
    I am new to the locating hardware side of embedded programming and so after being completely overwhelmed with all the choices out there (pc104, custom boards, a zillion option for each board, volume discounts, devel kits, ahhh!!) I am asking here for some direction. Basically, I must find a new motherboard and (most likely) re-implement the program logic. Rewriting this in C/C++/Java/C#/Pascal/BASIC is not a problem for me. so my real problem is finding the hardware. This motherboard will have several other devices attached to it. Here is a summary of what I need to do: Required: 2 RS232 serial ports (one used all the time for primary UI, the second one not continuous) 1 modem (9600+ baud ok) [Modem will be in simultaneous use with only one of the serial port devices, so interrupt sharing with one serial port is OK, but not both] Minimum permanent/long term storage: Whatever O/S requires + 1 MB (executable) + 512 KB (Data files) RAM: Minimal, whatever the O/S requires plus maybe 1MB for executable. Nice to have: USB port(s) Ethernet network port Wireless network Implementation languages (any O/S I will adapt to): First choice Java/C# (Mono ok) Second choice is C/Pascal Third is BASIC Ok, given all this, I am having a lot of trouble finding hardware that will support this that is low in cost. Every manufacturer site I visit has a lot of options, and it's difficult to see if their offering will even satisfy my must-have requirements (for example they sometimes list 3 "serial ports", but it appears that only one of the three is RS232, for example, and don't mention what the other two are). The #1 constraint is cost, #2 is size. Can anyone help me with this? This little task has left me thinking I should have gone for EE and not CS :-). EDIT: A bit of background: This is a system currently in production, but the original programmer passed away, and the current hardware manufacturer cannot find hardware to run the (currently) DOS system, so I need to reimplement this in a modern platform. I can only change the programming and the motherboard hardware.

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  • Rails - Help scoring an online quiz in RoR

    - by ChrisWesAllen
    I'm trying to grade a quiz application I would like to make. I have a questions model with and ask(the actual question), 4 choices(a-d), and a correct answer(string). In the view I have the 4 question being diplayed then the correct answer choice (This is just a test for functionality) and then I created a text_field to accept the users answer choice and a button to refresh the index action which has the scoring logic, for now.. --Do I need to put the text_field within a form_tag? <p>1. <%= h @question.q1 %></p> <p>2. <%= h @question.q2 %></p> <p>3. <%= h @question.q3 %></p> <p>4. <%= h @question.q4 %></p> <p>Answer: <%= h @question.correct %></p> <%= text_field_tag :choice, params[:choice] %> <%= button_to "Grade", {:controller => 'site', :action => "index"} %> <p> <%= @answer %></p> Heres the index controller action def index @question = Question.find(1) if @question.correct == params[:choice] @answer = 'right' else @answer = 'wrong' end end Its not really working. The textfield is supposed to take a letter choice like 'a' or 'c' and compare it with the correct answer in the database. I would love this to work by radiobuttons, but I'm a newbie to rails so I thought I'd take baby steps. So if anyone can help me with how to fix this by string, or preferably by radiobuttons, I'd really appreciate it.

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  • Django unit testing: South-migrated DB works in MySQL, throws duplicate PK error in PostGreSQL. Am I

    - by unclaimedbaggage
    Hi folks, (Worth starting off with a disclaimer: I'm very new to PostGreSQL) I have a django site which involves a standard app/tests.py testing file. If I migrate the DB to MySQL (through South),, the tests all pass. However in PostGresQL, I'm getting the following error: IntegrityError: duplicate key value violates unique constraint "business_contact_pkey" Note this happens while unit testing only - the actual page runs fine in both MySQL & PostGresql. Really having a heckuva time figuring this one out. Anyone have ideas? Below are the Postgresql "\d business_contact" & offending tests.py method if they help. No changes made to either DB except the (same) South migrations Thanks first_name | character varying(200) | not null mobile_phone | character varying(100) | surname | character varying(200) | not null business_id | integer | not null created | timestamp with time zone | not null deleted | boolean | not null default false updated | timestamp with time zone | not null slug | character varying(150) | not null phone | character varying(100) | email | character varying(75) | id | integer | not null default nextval('business_contact_id_seq'::regclass) Indexes: "business_contact_pkey" PRIMARY KEY, btree (id) "business_contact_slug_key" UNIQUE, btree (slug) "business_contact_business_id" btree (business_id) Foreign-key constraints: "business_id_refs_id_772cc1b7b40f4b36" FOREIGN KEY (business_id) REFERENCES business(id) DEFERRABLE INITIALLY DEFERRED Referenced by: TABLE "business" CONSTRAINT "primary_contact_id_refs_id_dfaf59c4041c850" FOREIGN KEY (primary_contact_id) REFERENCES business_contact(id) DEFERRABLE INITIALLY DEFERRED TEST DEF: def test_add_business_contact(self): """ Add a business contact """ contact_slug = 'test-new-contact-added-new-adf' business_id = 1 business = Business.objects.get(id=business_id) postdata = { 'first_name': 'Test', 'surname': 'User', 'business': '1', 'slug': contact_slug, 'email': '[email protected]', 'phone': '12345678', 'mobile_phone': '9823452', 'business': 1, 'business_id': 1, } #Test to ensure contacts that should not exist are not returned contact_not_exists = Contact.objects.filter(slug=contact_slug) self.assertFalse(contact_not_exists) #Add the contact and ensure it is present in the DB afterwards """ contact_add_url = '%s%s/contact/add/' % (settings.BUSINESS_URL, business.slug) self.client.post(contact_add_url, postdata) added_contact = Contact.objects.filter(slug=contact_slug) print added_contact try: self.assertTrue(added_contact) except: formset = ContactForm(postdata) print formset.errors self.assertFalse(True, "Contact not found in the database - most likely, the post values in the test didn't validate against the form")

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  • Bulletin board - Database optimisation

    - by andrew
    This question is a follow on from this Question The project and problem The project I am currently working on is a bulletin board for a large non-profit organisation. The bulletin board will be used to allow inter-office communication within the organisation. I am building the application and have been having trouble extracting the results that I need from my database because I don't think it is properly normalized and because of limitations in my knowledge of relational database theory and mysql. I would appreciate input into the design of the board in general and in particular, ways that the database structure can be improved to facilitate efficient queries and help me develop this application and future application faster Business Logic The bulletin board will be used in the following way Posting bulletins and responses to bulletins Employees or 'users' in offices around the country will be able to post messages to the bulletin board.Bulletins must be posted to a location and categorised- i'll call these "bulletins". Users will be able to post any number of replies to any one bulletin and users will be able to reply to their own bulletin - i'll call these 'replies'. Rating bulletins and replies Users will be able to either 'like' or 'dislike' a bulletin or a reply and the total number of likes or dislikes will be shown for each bulletin or reply. Viewing the bulletin board and responses Bulletins can be displayed chronologically. Users can sort bulletins chronologically or chronologically by the latest reply to that bulletin(let me know if you need more explanation) When a particular bulletin is selected, replies to that bulletin will be displayed chronologically @PerformanceDBA - edited 10:34 est 28/12/10I have begun implementing the data model. I assume that the 6th data model is the physical model because it contains the associative tables. I am going to post any questions that I have below. I will put up a database dump once I am done. I will then put up a list of all the queries that I need to run on the database and begin writing them. I hope you had a good Christmas. I'm in Canada and there's snow! Implementation of Physical model

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  • Finding Palindromes in an Array

    - by Jack L.
    For this assignemnt, I think that I got it right, but when I submit it online, it doesn't list it as correct even though I checked with Eclipse. The prompt: Write a method isPalindrome that accepts an array of Strings as its argument and returns true if that array is a palindrome (if it reads the same forwards as backwards) and /false if not. For example, the array {"alpha", "beta", "gamma", "delta", "gamma", "beta", "alpha"} is a palindrome, so passing that array to your method would return true. Arrays with zero or one element are considered to be palindromes. My code: public static void main(String[] args) { String[] input = new String[6]; //{"aay", "bee", "cee", "cee", "bee", "aay"} Should return true input[0] = "aay"; input[1] = "bee"; input[2] = "cee"; input[3] = "cee"; input[4] = "bee"; input[5] = "aay"; System.out.println(isPalindrome(input)); } public static boolean isPalindrome(String[] input) { for (int i=0; i<input.length; i++) { // Checks each element if (input[i] != input[input.length-1-i]){ return false; // If a single instance of non-symmetry } } return true; // If symmetrical, only one element, or zero elements } As an example, {"aay", "bee", "cee", "cee", "bee", "aay"} returns true in Eclipse, but Practice-It! says it returns false. What is going on?

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  • Creating a RESTful service in CakePHP

    - by NathanGaskin
    I'm attempting to create a RESTful service in CakePHP but I've hit a bit of a brick wall. I've enabled the default RESTful routing using Router::mapResources('users') and Router::parseExtensions(). This works well if I make a GET request, and returns some nicely formatted XML. So far so good. The problem is if I want to make a POST or PUT request. CakePHP doesn't seem to be able to read the data from the request. At the moment my add(), edit() and delete() actions don't contain any logic, they're simply setting $this-data to the view. I'm testing with the following cURL command: curl -v -d "<user><username>blahblah</username><password>blahblah</password>" http://localhost/users.xml --header 'content-type: text/xml' Which only returns a 404 header. If I remove the --header parameter then it returns the view but no data is set. It feels like I'm missing something obvious here. Any ideas?

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  • Reversible numerical calculations in Prolog

    - by user8472
    While reading SICP I came across logic programming chapter 4.4. Then I started looking into the Prolog programming language and tried to understand some simple assignments in Prolog. I found that Prolog seems to have troubles with numerical calculations. Here is the computation of a factorial in standard Prolog: f(0, 1). f(A, B) :- A > 0, C is A-1, f(C, D), B is A*D. The issues I find is that I need to introduce two auxiliary variables (C and D), a new syntax (is) and that the problem is non-reversible (i.e., f(5,X) works as expected, but f(X,120) does not). Naively, I expect that at the very least C is A-1, f(C, D) above may be replaced by f(A-1,D), but even that does not work. My question is: Why do I need to do this extra "stuff" in numerical calculations but not in other queries? I do understand (and SICP is quite clear about it) that in general information on "what to do" is insufficient to answer the question of "how to do it". So the declarative knowledge in (at least some) math problems is insufficient to actually solve these problems. But that begs the next question: How does this extra "stuff" in Prolog help me to restrict the formulation to just those problems where "what to do" is sufficient to answer "how to do it"?

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  • Deal with undefined values in code or in the template?

    - by David
    I'm writing a web application (in Python, not that it matters). One of the features is that people can leave comments on things. I have a class for comments, basically like so: class Comment: user = ... # other stuff where user is an instance of another class, class User: name = ... # other stuff And of course in my template, I have <div>${comment.user.name}</div> Problem: Let's say I allow people to post comments anonymously. In that case comment.user is None (undefined), and of course accessing comment.user.name is going to raise an error. What's the best way to deal with that? I see three possibilities: Use a conditional in the template to test for that case and display something different. This is the most versatile solution, since I can change the way anonymous comments are displayed to, say, "Posted anonymously" (instead of "Posted by ..."), but I've often been told that templates should be mindless display machines and not include logic like that. Also, other people might wind up writing alternate templates for the same application, and I feel like I should be making things as easy as possible for the template writer. Implement an accessor method for the user property of a Comment that returns a dummy user object when the real user is undefined. This dummy object would have user.name = 'Anonymous' or something like that and so the template could access it and print its name with no error. Put an actual record in my database corresponding to a user with user.name = Anonymous (or something like that), and just assign that user to any comment posted when nobody's logged in. I know I've seen some real-world systems that operate this way. (phpBB?) Is there a prevailing wisdom among people who write these sorts of systems about which of these (or some other solution) is the best? Any pitfalls I should watch out for if I go one way vs. another? Whoever gives the best explanation gets the checkmark.

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  • How to calculate commision based on referred memebrs?

    - by RAJKISHOR SAHU
    Hello everybody, I am developing a small software in C# WPF for a consultancy which does chain system business. I have coded tree structure to show who referred whom. Now it has commission depending on level. If 1 referred 2 & 3 then 1 will get level-1 commission. If 2 referred 4, 5 & 3 referred 6, 7 then 1 will receive level-2 commission. This chain will go on to certain total number. My problem is how I would implement this logic; I am able to calculate who has referred how many members via UDF written for adding TreeViewItem to TreeView. Or tell me how I can count items in treeview in certain level? Node adding UDF: public void AddNodes(int uid, TreeViewItem tSubNode) { string query = "select fullname, id from members where refCode=" + uid + ";"; MySqlCommand cmd = new MySqlCommand(query, db.conn); MySqlDataAdapter _DA = new MySqlDataAdapter(cmd); DataTable _DT = new DataTable(); tSubNode.IsExpanded = true; _DA.Fill(_DT); foreach (DataRow _dr in _DT.Rows) { TreeViewItem tNode = new TreeViewItem(); tNode.Header = _dr["fullname"].ToString()+" ("+_dr["id"].ToString()+")"; tSubNode.Items.Add(tNode); if (db.HasMembers(Convert.ToInt32(_dr["id"].ToString()))) { AddNodes(Convert.ToInt32(_dr["id"]), tNode); } } //This line tracks who has referred how many members Console.WriteLine("Tree node Count : "+tSubNode.Items.Count.ToString()+", UID "+uid); } Help me PLEASE!!!!

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  • Connecting to SQL Server 2005 via Web Service

    - by clear-cycle-corp
    Delphi 2010, dbExpress, and SQL Server 2005 DB I am trying to make a connection to a SQL Server 2005 DB using Delphi 2010 & DBExpress. If I create a standard delphi application and hard code my connection (IT WORKS!): procedure TForm1.Button1Click(Sender: TObject); var Conn: TSQLConnection; begin Conn:= TSQLConnection.Create(nil); Conn.ConnectionName:= 'VPUCDS_VPN_SE01'; Conn.LoadParamsOnConnect := True; Conn.LoginPrompt:=True; try Conn.Connected:= True; if Conn.Connected then ShowMessage('Connected!') else ShowMessage('NOT Connected!') finally Conn.Free; end; end; All the ini files, and DLLs reside in the same folder as my executable and yes, I have DBXMsSQL & MidasLib in the uses clause again, it works if its not a web service! However, if i then move the code over to a Web services CGI module: function TTest.ConnectToDB: Boolean;stdcall; var Conn: TSQLConnection; begin Conn:= TSQLConnection.Create(nil); Conn.ConnectionName:= 'VPUCDS_VPN_SE01'; Conn.LoadParamsOnConnect := True; Conn.LoginPrompt:=True; try Conn.Connected:= True; result:= Conn.Connected; finally Conn.Free; end; end; Thanks

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  • Validate a XDocument against schema without the ValidationEventHandler (for use in a HTTP handler)

    - by Vaibhav Garg
    Hi everyone, (I am new to Schema validation) Regarding the following method, System.Xml.Schema.Extensions.Validate( ByVal source As System.Xml.Linq.XDocument, ByVal schemas As System.Xml.Schema.XmlSchemaSet, ByVal validationEventHandler As System.Xml.Schema.ValidationEventHandler, ByVal addSchemaInfo As Boolean) I am using it as follows inside a IHttpHandler - Try Dim xsd As XmlReader = XmlReader.Create(context.Server.MapPath("~/App_Data/MySchema.xsd")) Dim schemas As New XmlSchemaSet() : schemas.Add("myNameSpace", xsd) : xsd.Close() myXDoxumentOdj.Validate(schemas, Function(s As Object, e As ValidationEventArgs) SchemaError(s, e, context), True) Catch ex1 As Threading.ThreadAbortException 'manage schema error' Return Catch ex As Exception 'manage other errors' End Try The handler- Function SchemaError(ByVal s As Object, ByVal e As ValidationEventArgs, ByVal c As HttpContext) As Object If c Is Nothing Then c = HttpContext.Current If c IsNot Nothing Then HttpContext.Current.Response.Write(e.Message) HttpContext.Current.Response.End() End If Return New Object() End Function This is working fine for me at present but looks very weak. I do get errors when I feed it bad XML. But i want to implement it in a more elegant way. This looks like it would break for large XML etc. Is there some way to validate without the handler so that I get the document validated in one go and then deal with errors? To me it looks Async such that the call to Validate() would pass and some non deterministic time later the handler would get called with the result/errors. Is that right? Thanks and sorry for any goofy mistakes :).

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  • Android NDK import-module / code reuse

    - by Graeme
    Morning! I've created a small NDK project which allows dynamic serialisation of objects between Java and C++ through JNI. The logic works like this: Bean - JavaCInterface.Java - JavaCInterface.cpp - JavaCInterface.java - Bean The problem is I want to use this functionality in other projects. I separated out the test code from the project and created a "Tester" project. The tester project sends a Java object through to C++ which then echo's it back to the Java layer. I thought linking would be pretty simple - ("Simple" in terms of NDK/JNI is usually a day of frustration) I added the JNIBridge project as a source project and including the following lines to Android.mk: NDK_MODULE_PATH=.../JNIBridge/jni/" JNIBridge/jni/JavaCInterface/Android.mk: ... include $(BUILD_STATIC_LIBRARY) JNITester/jni/Android.mk: ... include $(BUILD_SHARED_LIBRARY) $(call import-module, JavaCInterface) This all works fine. The C++ files which rely on headers from JavaCInterface module work fine. Also the Java classes can happily use interfaces from JNIBridge project. All the linking is happy. Unfortunately JavaCInterface.java which contains the native method calls cannot see the JNI method located in the static library. (Logically they are in the same project but both are imported into the project where you wish to use them through the above mechanism). My current solutions are are follows. I'm hoping someone can suggest something that will preserve the modular nature of what I'm trying to achieve: My current solution would be to include the JavaCInterface cpp files in the calling project like so: LOCAL_SRC_FILES := FunctionTable.cpp $(PATH_TO_SHARED_PROJECT)/JavaCInterface.cpp But I'd rather not do this as it would lead to me needing to update each depending project if I changed the JavaCInterface architecture. I could create a new set of JNI method signatures in each local project which then link to the imported modules. Again, this binds the implementations too tightly.

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  • How to do HABTM management with auto completion in Rails?

    - by Andrei
    I am looking for a good solution for a probably typical problem of managing models with HABTM association in Rails. Let's assume that we have two models -- products and categories: Products has_many :categorizations has_many :categories, :through => :categorizations Categories has_many :categorizations has_many :products, :through => :categorizations Categorization belongs_to :product belongs_to :category Pat Shaughnessy is developing modified auto_complete plugin which can allow to manage one-to-many (and many-to-many) association: For someone that would be enough, but I don't really like so many text fields. I guess it is possible to combine the Ryan Bates' screencasts used by Pat in a slightly different way, namely, using one text field with autocomplete: Also it would be better to remove from the list of suggested tasks (one-to-many), or products|categories (many-to-many) those which have been already added. In the case of products-categories relationship, such auto completion would be used both in the form for product, and in the form for category. I hope that there is an existing plugin for that. I am not very experienced in Ruby, and don't really know how to implement such logic by myself. Any help is appreciated!

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  • Sending buffered images between Java client and Twisted Python socket server

    - by PattimusPrime
    I have a server-side function that draws an image with the Python Imaging Library. The Java client requests an image, which is returned via socket and converted to a BufferedImage. I prefix the data with the size of the image to be sent, followed by a CR. I then read this number of bytes from the socket input stream and attempt to use ImageIO to convert to a BufferedImage. In abbreviated code for the client: public String writeAndReadSocket(String request) { // Write text to the socket BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())); bufferedWriter.write(request); bufferedWriter.flush(); // Read text from the socket BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream())); // Read the prefixed size int size = Integer.parseInt(bufferedReader.readLine()); // Get that many bytes from the stream char[] buf = new char[size]; bufferedReader.read(buf, 0, size); return new String(buf); } public BufferedImage stringToBufferedImage(String imageBytes) { return ImageIO.read(new ByteArrayInputStream(s.getBytes())); } and the server: # Twisted server code here # The analog of the following method is called with the proper client # request and the result is written to the socket. def worker_thread(): img = draw_function() buf = StringIO.StringIO() img.save(buf, format="PNG") img_string = buf.getvalue() return "%i\r%s" % (sys.getsizeof(img_string), img_string) This works for sending and receiving Strings, but image conversion (usually) fails. I'm trying to understand why the images are not being read properly. My best guess is that the client is not reading the proper number of bytes, but I honestly don't know why that would be the case. Side notes: I realize that the char[]-to-String-to-bytes-to-BufferedImage Java logic is roundabout, but reading the bytestream directly produces the same errors. I have a version of this working where the client socket isn't persistent, ie. the request is processed and the connection is dropped. That version works fine, as I don't need to care about the image size, but I want to learn why the proposed approach doesn't work.

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  • Some languages don't work when using Word 2007 Spellcheck from Interop

    - by Tridus
    I'm using the Word 2007 spellchecker via Interop in a VB.net desktop app. When using the default language (English), it works fine. If I set the language to French via LanguageId, it also works. But if I set it to French (Canadian) (Word.WdLanguageID.wdFrenchCanadian), it doesn't work. There's no error message, it simply runs and says the document contains no errors. I know it does, if I paste the exact same text into Word itself and run it with the French (Canadian) dictionary, it finds errors. Just why that dictionary doesn't work is kind of a mystery to me. Full code below: Public Shared Function SpellCheck(ByVal text As String, ByVal checkGrammar As Boolean) As String ' If there is no data to spell check, then exit sub here. If text.Length = 0 Then Return text End If Dim objWord As Word.Application Dim objTempDoc As Word.Document ' Declare an IDataObject to hold the data returned from the ' clipboard. Dim iData As IDataObject objWord = New Word.Application() objTempDoc = objWord.Documents.Add objWord.Visible = False ' Position Word off the screen...this keeps Word invisible ' throughout. objWord.WindowState = 0 objWord.Top = -3000 ' Copy the contents of the textbox to the clipboard Clipboard.SetDataObject(text) ' With the temporary document, perform either a spell check or a ' complete ' grammar check, based on user selection. With objTempDoc .Content.Paste() .Activate() .Content.LanguageID = Word.WdLanguageID.wdFrenchCanadian If checkGrammar Then .CheckGrammar() Else .CheckSpelling() End If ' After user has made changes, use the clipboard to ' transfer the contents back to the text box .Content.Copy() iData = Clipboard.GetDataObject If iData.GetDataPresent(DataFormats.Text) Then text = CType(iData.GetData(DataFormats.Text), _ String) End If .Saved = True .Close() End With objWord.Quit() Return text End Function

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  • Numerical calculations in Prolog

    - by user8472
    While reading SICP I came across logic programming chapter 4.4. Then I started looking into the Prolog programming language and tried to understand some simple assignments in Prolog. I found that Prolog seems to have troubles with numerical calculations. Here is the computation of a factorial in standard Prolog: f(0, 1). f(A, B) :- A > 0, C is A-1, f(C, D), B is A*D. The issues I find is that I need to introduce two auxiliary variables (C and D), a new syntax (is) and that the problem is non-reversible (i.e., f(5,X) works as expected, but f(X,120) does not). Naively, I expect that at the very least C is A-1, f(C, D) above may be replaced by f(A-1,D), but even that does not work. My question is: Why do I need to do this extra "stuff" in numerical calculations but not in other queries? I do understand (and SICP is quite clear about it) that in general information on "what to do" is insufficient to answer the question of "how to do it". So the declarative knowledge in (at least some) math problems is insufficient to actually solve these problems. But that begs the next question: How does this extra "stuff" in Prolog help me to restrict the formulation to just those problems where "what to do" is sufficient to answer "how to do it"?

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  • Parallel.Foreach loop creating multiple db connections throws connection errors?

    - by shawn.mek
    Login failed. The login is from an untrusted domain and cannot be used with Windows authentication I wanted to get my code running in parallel, so I changed my foreach loop to a parallel foreach loop. It seemed simple enough. Each loop connects to the database, looks up some stuff, performs some logic, adds some stuff, closes the connection. But I get the above error? I'm using my local sql server and entity framework (each loop uses it's own context). Is there some problem with connecting multiple times using the same local login or something? How did I get around this? I have (before trying to covert to a parallel.foreach loop) split my list of objects that I am foreach looping through into four groups (separate csv files) and run four concurrent instances of my program (which ran faster overall than just one, thus the idea for parallel). So it seems connecting to the db shouldn't be a problem? Any ideas? EDIT: Here's before var gtgGenerator = new CustomGtgGenerator(); var connectionString = ConfigurationManager.ConnectionStrings["BioEntities"].ConnectionString; var allAccessionsFromObs = _GetAccessionListFromDataFiles(collectionId); ForEach(cloneIdAndAccessions in allAccessionsFromObs) DoWork(gtgGenerator, taxonId, organismId, cloneIdAndAccessions, connectionString)); after var gtgGenerator = new CustomGtgGenerator(); var connectionString = ConfigurationManager.ConnectionStrings["BioEntities"].ConnectionString; var allAccessionsFromObs = _GetAccessionListFromDataFiles(collectionId); Parallel.ForEach(allAccessionsFromObs, cloneIdAndAccessions => DoWork(gtgGenerator, taxonId, organismId, cloneIdAndAccessions, connectionString)); Inside the DoWork I use the BioEntities using (var bioEntities = new BioEntities(connectionString)) {...}

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  • Simulating a contains If-Else using RewriteCond

    - by hlissner
    Hi! I'm trying to get my head around RewriteCond, and want to rewrite any requests either to a static html page (if it exists), or to a specific index.php (so long as the requested file doesn't exist). To illustrate the logic: if HTTP_HOST is '(www\.)?mydomain.com' if file exists: "/default/static/{REQUEST_URI}.html", then rewrite .* to /default/static/{REQUEST_URI}.html else if file exists: {REQUEST_FILENAME}, then do not rewrite else rewrite .* to /default/index.php I don't seem to have much trouble doing it when I don't need to test for the HTTP_HOST. Ultimately, this one .htaccess file will be handling requests for several domains. I know I could get around this with vhosts, but I'd like to figure out how to do it this way. Here's where I am at now: RewriteCond %{HTTP_HOST} ^(www\.)?mydomain\.com$ [NC] RewriteCond /default/static/%{REQUEST_URI}.html -f RewriteRule . /default/static/%{REQUEST_URI}.html [L,NC] RewriteCond %{REQUEST_FILENAME} !-f RewriteRule . /default/index.php [L,QSA] I'm not too familiar with some of the other flags, will any of them be of use here (like chain|C, next|N or skip|S)? Thanks in advance!

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  • VB.NET editing existing that with a form

    - by user127147
    Hi there, I have a simple questions that puzzles me. I need a little bit of refreashment with VB as I have been away for a while. I have a form that adds new contacts. New contacts are added by pressing an appropriate button and they appear as an entry in the list on the form. I try now to add an edit button that will edit existing entries. User will select a given entry on the list and press edit button and will be presented with an appropriate form (AddContFrm). Right now it simply adds another entry with the same title. Logic is handled in a class called Contact.vb Here is my code. Public Class Contact Public Contact As String Public Title As String Public Fname As String Public Surname As String Public Address As String Private myCont As String Public Property Cont() Get Return myCont End Get Set(ByVal value) myCont = Value End Set End Property Public Overrides Function ToString() As String Return Me.Cont End Function Sub NewContact() FName = frmAddCont.txtFName.ToString frmStart.lstContact.Items.Add(FName) frmAddCont.Hide() End Sub Public Sub Display() Dim C As New Contact 'C.Cont = InputBox("Enter a title for this contact.") C.Cont = frmAddCont.txtTitle.Text C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text 'frmStart.lstContact.Items.Add(C.Cont.ToString) frmStart.lstContact.Items.Add(C) End Sub End Class AddContFrm Public Class frmAddCont Public Class ControlObject Dim Title As String Dim FName As String Dim SName As String Dim Address As String Dim TelephoneNumber As Integer Dim emailAddress As String Dim Website As String Dim Photograph As String End Class Private Sub btnConfirmAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConfirmAdd.Click Dim C As New Contact C.Display() Me.Hide() End Sub Private Sub frmAddCont_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load End Sub End Class and frmStart.vb Public Class frmStart Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click frmAddCont.Show() End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDel.Click Dim DelCont As Contact DelCont = Me.lstContact.SelectedItem() lstContact.Items.Remove(DelCont) End Sub Private Sub lstContact_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstContact.SelectedIndexChanged End Sub Private Sub btnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEdit.Click Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = DirectCast(lstContact.SelectedItem, Contact) C.Display() End If End Sub End Class

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  • WPF validation on Enter Key Up

    - by Martin
    I'm trying to validate a UI change when Enter key is pressed. The UI element is a textbox, which is data binded to a string. My problem is that the data binding hasn't updated TestText when Enter key is Up. It is only updated when I press the button which brings up a message box. /// <summary> /// Interaction logic for Window1.xaml /// </summary> public partial class Window1 : Window, INotifyPropertyChanged { String _testText = new StringBuilder("One").ToString(); public string TestText { get { return _testText; } set { if (value != _testText) { _testText = value; OnPropertyChanged("TestText"); } } } public Window1() { InitializeComponent(); myGrid.DataContext = this; } private void OnPropertyChanged(string property) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(property)); } } public event PropertyChangedEventHandler PropertyChanged; private void onKeyUp(object sender, KeyEventArgs e) { if (e.Key != System.Windows.Input.Key.Enter) return; System.Diagnostics.Trace.WriteLine(TestText); } private void button1_Click(object sender, RoutedEventArgs e) { MessageBox.Show(TestText); } } Window XAML: Window x:Class="VerificationTest.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="300" Width="300" KeyUp="onKeyUp" TextBox XAML: TextBox Name="myTextBox" Text="{Binding TestText}" Button XAML: Button Name="button1" Click="button1_Click"

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  • Can someone please clarify my understanding of a mock's Verify concept?

    - by Pure.Krome
    Hi folks, I'm playing around with some unit tests and mocking. I'm trying to verify that some code, in my method, has been called. I don't think I understand the Verify part of mocking right, because I can only ever Verify main method .. which is silly because that is what I Act upon anyways. I'm trying to test that my logic is working - so I thought I use Verify to see that certain steps in the method have been reached and enacted upon. Lets use this example to highlight what I am doing wrong. public interface IAuthenticationService { bool Authenticate(string username, string password); SignOut(); } public class FormsAuthenticationService : IAuthenticationService { public bool Authenticate(string username, string password) { var user = _userService.FindSingle(x => x.UserName == username); if (user == null) return false; // Hash their password. var hashedPassword = EncodePassword(password, user.PasswordSalt); if (!hashedPassword.Equals(password, StringComparison.InvariantCulture)) return false; FormsAuthentication.SetAuthCookie(userName, true); return true; } } So now, I wish to verify that EncodePassword was called. FormsAuthentication.SetAuthCookie(..) was called. Now, I don't care about the implimentations of both of those. And more importantly, I do not want to test those methods. That has to be handled elsewhere. What I though I should do is Verify that those methods were called and .. if possible ... an expected result was returned. Is this the correct understanding of what 'Verify' means with mocking? If so, can someone show me how I can do this. Preferable with moq but i'm happy with anything. Cheers :)

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  • jQuery AJAX chained calls + Celery in Django

    - by user1029968
    Currently clicking one of the links in my application, triggers AJAX call (GET) that - if succeeds - triggers the second one and this second one - if succeeds - calls the third one. This way user can be informed which part of process started when clicking the link is currently ongoing. So in the template file in Django project, click callback body for link mentioned looks like below: $("#the-link").click(function(item)) { // CALL 1 $.ajax({ url: {% url ajax_call_1 %}, data: { // something } }) .done(function(call1Result) { // CALL 2 $.ajax({ url: {% url ajax_call_1 %}, data: { // call1Result passed here to CALL 2 } }) .done(function(call2Result) { // CALL 3 $.ajax({ url: {%url ajax_call_3 %}, data: { // call2Result passed here to CALL 3 } }) .done(function(call3Result) { // expected result if everything went fine console.log("wow, it worked!"); console.log(call3Result); }) .fail(function(errorObject) { console.log("call3 failed"); console.log(errorObject); } }) .fail(function(errorObject)) { console.log("call2 failed"); console.log(errorObject); } }) .fail(function(errorObject) { console.log("call1 failed"); console.log(errorObject); }); }); This works fine for me. The thing is, I'd like to prevent interrupting the following calls if the user closes the browser and the calls are not finished (as it will take some time to finish all three), as there is some additional logic in Django view functions called in each GET request. For example, if user clicks the link and closes the browser during CALL 1, is it possible to somehow go on with the following CALL 2 and CALL 3? I know that normally I'd be able to use Celery Task to process the function but is it still possible here with the chained calls mentioned? Any help is much appreciated!

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  • Object Design: How to Organize/Structure a "Collection Class"

    - by CrimsonX
    I'm currently struggling to understand how I should organize/structure a class which I have already created. The class does the following: As its input in the constructor, it takes a collection of logs In the constructor it validates and filters the logs through a series of algorithms implementing my business logic After all filtering and validation is complete, it returns a collection (a List) of the valid and filtered logs which can be presented to the user graphically in a UI. Here is some simplified code describing what I'm doing: class FilteredCollection { public FilteredCollection( SpecialArray<MyLog> myLog) { // validate inputs // filter and validate logs in collection // in end, FilteredLogs is ready for access } Public List<MyLog> FilteredLogs{ get; private set;} } However, in order to access this collection, I have to do the following: var filteredCollection = new FilteredCollection( secialArrayInput ); //Example of accessing data filteredCollection.FilteredLogs[5].MyLogData; Other key pieces of input: I foresee only one of these filtered collections existing in the application (therefore should I make it a static class? Or perhaps a singleton?) Testability and flexibility in creation of the object is important (Perhaps therefore I should keep this an instanced class for testability?) I'd prefer to simplify the dereferencing of the logs if at all possible, as the actual variable names are quite long and it takes some 60-80 characters to just get to the actual data. My attempt in keeping this class simple is that the only purpose of the class is to create this collection of validated data. I know that there may be no "perfect" solution here, but I'm really trying to improve my skills with this design and I would greatly appreciate advice to do that. Thanks in advance.

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  • Ideas Needed for a Base Code System

    - by Tegan Snyder
    I've developed a PHP web application that is currently in need of a strategic restructuring. Currently when we setup new clients we give them the entire code base on a subdomain of our main domain and create a new table for them in the database. This results in each client having the entire codebase, meaning when we make bug changes, fixes we have to go back and apply them independently across all clients and this is a pain. What I'd like to create is a base code server that holds all the core PHP files. base.domain.com Then all of our clients (client.domain.com) will only need a few files: config.php would have the database connection information. index.php - displays the login box if session non-existant, otherwise it loads baseline code via remote includes to base.domain.com. My question is does my logic seem feasible? How do other people handle similar situations by having a base code? Also.... Is it even possbile to remotely include PHP files from base.domain.com and include them in client.domain.com? Thanks, Tegan

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