Search Results

Search found 5793 results on 232 pages for 'book exercise'.

Page 226/232 | < Previous Page | 222 223 224 225 226 227 228 229 230 231 232  | Next Page >

  • Is the Unix Philosophy still relevant in the Web 2.0 world?

    - by David Titarenco
    Introduction Hello, let me give you some background before I begin. I started programming when I was 5 or 6 on my dad's PSION II (some primitive BASIC-like language), then I learned more and more, eventually inching my way up to C, C++, Java, PHP, JS, etc. I think I'm a pretty decent coder. I think most people would agree. I'm not a complete social recluse, but I do stuff like write a virtual machine for fun. I've never taken a computer course in college because I've been in and out for the past couple of years and have only been taking core classes; never having been particularly amazing at school, perhaps I'm missing some basic tenet that most learn in CS101. I'm currently reading Coders at Work and this question is based on some ideas I read in there. A Brief (Fictionalized) Example So a certain sunny day I get an idea. I hire a designer and hammer away at some C/C++ code for a couple of months, soon thereafter releasing silvr.com, a website that transmutes lead into silver. Yep, I started my very own start-up and even gave it a clever web 2.0 name with a vowel missing. Mom and dad are proud. I come up with some numbers I should be seeing after 1, 2, 3, 6, 9, 12 months and set sail. Obviously, my transmuting server isn't perfect, sometimes it segfaults, sometimes it leaks memory. I fix it and keep truckin'. After all, gdb is my best friend. Eventually, I'm at a position where a very small community of people are happily transmuting lead into silver on a semi-regular basis, but they want to let their friends on MySpace know how many grams of lead they transmuted today. And they want to post images of their lead and silver nuggets on flickr. I'm losing out on potential traffic unless I let them log in with their Yahoo, Google, and Facebook accounts. They want webcam support and live cock fighting, merry-go-rounds and Jabberwockies. All these things seem necessary. The Aftermath Of course, I have to re-write the transmuting server! After all, I've been losing money all these months. I need OAuth libraries and OpenID libraries, JSON support, and the only stable Jabberwocky API is for Java. C++ isn't even an option anymore. I'm just one guy! The Java binary just grows and grows since I need some legacy Apache include for the JSON library, and some antiquated Sun dependency for OAuth support. Then I pick up a book like Coders at Work and read what people like jwz say about complexity... I think to myself.. Keep it simple, stupid. I like simple things. I've always loved the Unix Philosophy but even after trying to keep the new server source modular and sleek, I loathe having to write one more line of code. It feels that I'm just piling crap on top of other crap. Maybe I'm naive thinking every piece of software can be simple and clever. Maybe it's just a phase.. or is the Unix Philosophy basically dead when it comes to the current state of (web) development? I'm just kind of disheartened :(

    Read the article

  • Domain Validation in a CQRS architecture

    - by Jupaol
    Basically I want to know if there is a better way to validate my domain entities. This is how I am planning to do it but I would like your opinion The first approach I considered was: class Customer : EntityBase<Customer> { public void ChangeEmail(string email) { if(string.IsNullOrWhitespace(email)) throw new DomainException(“...”); if(!email.IsEmail()) throw new DomainException(); if(email.Contains(“@mailinator.com”)) throw new DomainException(); } } I actually do not like this validation because even when I am encapsulating the validation logic in the correct entity, this is violating the Open/Close principle (Open for extension but Close for modification) and I have found that violating this principle, code maintenance becomes a real pain when the application grows up in complexity. Why? Because domain rules change more often than we would like to admit, and if the rules are hidden and embedded in an entity like this, they are hard to test, hard to read, hard to maintain but the real reason why I do not like this approach is: if the validation rules change, I have to come and edit my domain entity. This has been a really simple example but in RL the validation could be more complex So following the philosophy of Udi Dahan, making roles explicit, and the recommendation from Eric Evans in the blue book, the next try was to implement the specification pattern, something like this class EmailDomainIsAllowedSpecification : IDomainSpecification<Customer> { private INotAllowedEmailDomainsResolver invalidEmailDomainsResolver; public bool IsSatisfiedBy(Customer customer) { return !this.invalidEmailDomainsResolver.GetInvalidEmailDomains().Contains(customer.Email); } } But then I realize that in order to follow this approach I had to mutate my entities first in order to pass the value being valdiated, in this case the email, but mutating them would cause my domain events being fired which I wouldn’t like to happen until the new email is valid So after considering these approaches, I came out with this one, since I am going to implement a CQRS architecture: class EmailDomainIsAllowedValidator : IDomainInvariantValidator<Customer, ChangeEmailCommand> { public void IsValid(Customer entity, ChangeEmailCommand command) { if(!command.Email.HasValidDomain()) throw new DomainException(“...”); } } Well that’s the main idea, the entity is passed to the validator in case we need some value from the entity to perform the validation, the command contains the data coming from the user and since the validators are considered injectable objects they could have external dependencies injected if the validation requires it. Now the dilemma, I am happy with a design like this because my validation is encapsulated in individual objects which brings many advantages: easy unit test, easy to maintain, domain invariants are explicitly expressed using the Ubiquitous Language, easy to extend, validation logic is centralized and validators can be used together to enforce complex domain rules. And even when I know I am placing the validation of my entities outside of them (You could argue a code smell - Anemic Domain) but I think the trade-off is acceptable But there is one thing that I have not figured out how to implement it in a clean way. How should I use this components... Since they will be injected, they won’t fit naturally inside my domain entities, so basically I see two options: Pass the validators to each method of my entity Validate my objects externally (from the command handler) I am not happy with the option 1 so I would explain how I would do it with the option 2 class ChangeEmailCommandHandler : ICommandHandler<ChangeEmailCommand> { public void Execute(ChangeEmailCommand command) { private IEnumerable<IDomainInvariantValidator> validators; // here I would get the validators required for this command injected, and in here I would validate them, something like this using (var t = this.unitOfWork.BeginTransaction()) { var customer = this.unitOfWork.Get<Customer>(command.CustomerId); this.validators.ForEach(x =. x.IsValid(customer, command)); // here I know the command is valid // the call to ChangeEmail will fire domain events as needed customer.ChangeEmail(command.Email); t.Commit(); } } } Well this is it. Can you give me your thoughts about this or share your experiences with Domain entities validation EDIT I think it is not clear from my question, but the real problem is: Hiding the domain rules has serious implications in the future maintainability of the application, and also domain rules change often during the life-cycle of the app. Hence implementing them with this in mind would let us extend them easily. Now imagine in the future a rules engine is implemented, if the rules are encapsulated outside of the domain entities, this change would be easier to implement

    Read the article

  • How color attributes work in VBO?

    - by Jayesh
    I am coding to OpenGL ES 2.0 (Webgl). I am using VBOs to draw primitives. I have vertex array, color array and array of indices. I have looked at sample codes, books and tutorial, but one thing I don't get - if color is defined per vertex how does it affect the polygonal surfaces adjacent to those vertices? (I am a newbie to OpenGL(ES)) I will explain with an example. I have a cube to draw. From what I read in OpenGLES book, the color is defined as an vertex attribute. In that case, if I want to draw 6 faces of the cube with 6 different colors how should I define the colors. The source of my confusion is: each vertex is common to 3 faces, then how will it help defining a color per vertex? (Or should the color be defined per index?). The fact that we need to subdivide these faces into triangles, makes it harder for me to understand how this relationship works. The same confusion goes for edges. Instead of drawing triangles, let's say I want to draw edges using LINES primitives. Each edge of different color. How am I supposed to define color attributes in that case? I have seen few working examples. Specifically this tutorial: http://learningwebgl.com/blog/?p=370 I see how color array is defined in the above example to draw a cube with 6 different colored faces, but I don't understand why is defined that way. (Why is each color copied 4 times into unpackedColors for instance?) Can someone explain how color attributes work in VBO? [The link above seems inaccessible, so I will post the relevant code here] cubeVertexPositionBuffer = gl.createBuffer(); gl.bindBuffer(gl.ARRAY_BUFFER, cubeVertexPositionBuffer); vertices = [ // Front face -1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 1.0, // Back face -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, -1.0, // Top face -1.0, 1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, -1.0, // Bottom face -1.0, -1.0, -1.0, 1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, -1.0, 1.0, // Right face 1.0, -1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 1.0, // Left face -1.0, -1.0, -1.0, -1.0, -1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, -1.0, ]; gl.bufferData(gl.ARRAY_BUFFER, new WebGLFloatArray(vertices), gl.STATIC_DRAW); cubeVertexPositionBuffer.itemSize = 3; cubeVertexPositionBuffer.numItems = 24; cubeVertexColorBuffer = gl.createBuffer(); gl.bindBuffer(gl.ARRAY_BUFFER, cubeVertexColorBuffer); var colors = [ [1.0, 0.0, 0.0, 1.0], // Front face [1.0, 1.0, 0.0, 1.0], // Back face [0.0, 1.0, 0.0, 1.0], // Top face [1.0, 0.5, 0.5, 1.0], // Bottom face [1.0, 0.0, 1.0, 1.0], // Right face [0.0, 0.0, 1.0, 1.0], // Left face ]; var unpackedColors = [] for (var i in colors) { var color = colors[i]; for (var j=0; j < 4; j++) { unpackedColors = unpackedColors.concat(color); } } gl.bufferData(gl.ARRAY_BUFFER, new WebGLFloatArray(unpackedColors), gl.STATIC_DRAW); cubeVertexColorBuffer.itemSize = 4; cubeVertexColorBuffer.numItems = 24; cubeVertexIndexBuffer = gl.createBuffer(); gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, cubeVertexIndexBuffer); var cubeVertexIndices = [ 0, 1, 2, 0, 2, 3, // Front face 4, 5, 6, 4, 6, 7, // Back face 8, 9, 10, 8, 10, 11, // Top face 12, 13, 14, 12, 14, 15, // Bottom face 16, 17, 18, 16, 18, 19, // Right face 20, 21, 22, 20, 22, 23 // Left face ] gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new WebGLUnsignedShortArray(cubeVertexIndices), gl.STATIC_DRAW); cubeVertexIndexBuffer.itemSize = 1; cubeVertexIndexBuffer.numItems = 36;

    Read the article

  • How do I get confidence intervals without inverting a singular Hessian matrix?

    - by AmalieNot
    Hello. I recently posted this to reddit and it was suggested I come here, so here I am. I'm a student working on an epidemiology model in R, using maximum likelihood methods. I created my negative log likelihood function. It's sort of gross looking, but here it is: NLLdiff = function(v1, CV1, v2, CV2, st1 = (czI01 - czV01), st2 = (czI02 - czV02), st01 = czI01, st02 = czI02, tt1 = czT01, tt2 = czT02) { prob1 = (1 + v1 * CV1 * tt1)^(-1/CV1) prob2 = ( 1 + v2 * CV2 * tt2)^(-1/CV2) -(sum(dbinom(st1, st01, prob1, log = T)) + sum(dbinom(st2, st02, prob2, log = T))) } The reason the first line looks so awful is because most of the data it takes is inputted there. czI01, for example, is already declared. I did this simply so that my later calls to the function don't all have to have awful vectors in them. I then optimized for CV1, CV2, v1 and v2 using mle2 (library bbmle). That's also a bit gross looking, and looks like: ml.cz.diff = mle2 (NLLdiff, start=list(v1 = vguess, CV1 = cguess, v2 = vguess, CV2 = cguess), method="L-BFGS-B", lower = 0.0001) Now, everything works fine up until here. ml.cz.diff gives me values that I can turn into a plot that reasonably fits my data. I also have several different models, and can get AICc values to compare them. However, when I try to get confidence intervals around v1, CV1, v2 and CV2 I have problems. Basically, I get a negative bound on CV1, which is impossible as it actually represents a square number in the biological model as well as some warnings. The warnings are this: http://i.imgur.com/B3H2l.png . Is there a better way to get confidence intervals? Or, really, a way to get confidence intervals that make sense here? What I see happening is that, by coincidence, my hessian matrix is singular for some values in the optimization space. But, since I'm optimizing over 4 variables and don't have overly extensive programming knowledge, I can't come up with a good method of optimization that doesn't rely on the hessian. I have googled the problem - it suggested that my model's bad, but I'm reconstructing some work done before which suggests that my model's really not awful (the plots I make using the ml.cz.diff look like the plots of the original work). I have also read the relevant parts of the manual as well as Bolker's book Ecological Models in R. I have also tried different optimization methods, which resulted in a longer run time but the same errors. The "SANN" method didn't finish running within an hour, so I didn't wait around to see the result. tl;dr : my confidence intervals are bad, is there a relatively straightforward way to fix them in R. My vectors are: czT01 = c(5, 5, 5, 5, 5, 5, 5, 25, 25, 25, 25, 25, 25, 25, 50, 50, 50, 50, 50, 50, 50) czT02 = c(5, 5, 5, 5, 5, 10, 10, 10, 10, 10, 25, 25, 25, 25, 25, 50, 50, 50, 50, 50, 75, 75, 75, 75, 75) czI01 = c(25, 24, 22, 22, 26, 23, 25, 25, 25, 23, 25, 18, 21, 24, 22, 23, 25, 23, 25, 25, 25) czI02 = c(13, 16, 5, 18, 16, 13, 17, 22, 13, 15, 15, 22, 12, 12, 13, 13, 11, 19, 21, 13, 21, 18, 16, 15, 11) czV01 = c(1, 4, 5, 5, 2, 3, 4, 11, 8, 1, 11, 12, 10, 16, 5, 15, 18, 12, 23, 13, 22) czV02 = c(0, 3, 1, 5, 1, 6, 3, 4, 7, 12, 2, 8, 8, 5, 3, 6, 4, 6, 11, 5, 11, 1, 13, 9, 7) and I get my guesses by: v = -log((c(czI01, czI02) - c(czV01, czV02))/c(czI01, czI02))/c(czT01, czT02) vguess = mean(v) cguess = var(v)/vguess^2 It's also possible that I'm doing something else completely wrong, but my results seem reasonable so I haven't caught it.

    Read the article

  • what is the point of escaping quotation marks in php

    - by Jacksta
    Here is a validation script from a book I am learning, Why is escaping the quotation marks necassery? e.g. <option value=\"char\">char</option> <?php //validate important input if ((!$_POST[table_name]) || (!$_POST[num_fields])) { header( "location: show_createtable.html"); exit; } //begin creating form for display $form_block = " <form action=\"do_createtable.php\" method=\"post\"> <input name=\"table_name\" type=\"hidden\" value=\"$_POST[table_name]\"> <table cellspacing=\"5\" cellpadding=\"5\"> <tr> <th>Field Name</th><th>Field Type</th><th>Table Length</th> </tr>"; //count from 0 until you reach the number fo fields for ($i = 0; $i <$_POST[num_fields]; $i++) { $form_block .=" <tr> <td align=center><input type=\"texr\" name=\"field name[]\" size=\"30\"></td> <td align=center> <select name=\"field_type[]\"> <option value=\"char\">char</option> <option value=\"date\">date</option> <option value=\"float\">float</option> <option value=\"int\">int</option> <option value=\"text\">text</option> <option value=\"varchar\">varchar</option> </select> </td> <td align=center><input type=\"text\" name=\"field_length[]\" size=\"5\"> </td> </tr>"; } //finish up the form $form_block .= " <tr> <td align=center colspan=3><input type =\"submit\" value=\"create table\"> </td> </tr> </table> </form>"; ?> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Create a database table: Step 2</title> </head> <body> <h1>defnie fields for <? echo "$_POST[table_name]"; ?> </h1> <? echo "$form_block"; ?> </body> </html>

    Read the article

  • Why does my Ajax function returns my entire code?

    - by JDelage
    I'm playing with sample code from the book "Head first Ajax". Here are the salient pieces of code: Index.php - html piece: <body> <div id="wrapper"> <div id="thumbnailPane"> <img src="images/itemGuitar.jpg" width="301" height="105" alt="guitar" title="itemGuitar" id="itemGuitar" onclick="getDetails(this)"/> <img src="images/itemShades.jpg" alt="sunglasses" width="301" height="88" title="itemShades" id="itemShades" onclick="getDetails(this)" /> <img src="images/itemCowbell.jpg" alt="cowbell" width="301" height="126" title="itemCowbell" id="itemCowbell" onclick="getDetails(this)" /> <img src="images/itemHat.jpg" alt="hat" width="300" height="152" title="itemHat" id="itemHat" onclick="getDetails(this)" /> </div> <div id="detailsPane"> <img src="images/blank-detail.jpg" width="346" height="153" id="itemDetail" /> <div id="description"></div> </div> </div> </body> Index.php - script: function getDetails(img){ var title = img.title; request = createRequest(); if (request == null) { alert("Unable to create request"); return; } var url= "getDetails.php?ImageID=" + escape(title); request.open("GET", url, true); request.onreadystatechange = displayDetails; request.send(null); } function displayDetails() { if (request.readyState == 4) { if (request.status == 200) { detailDiv = document.getElementById("description"); detailDiv.innerHTML = request.responseText; }else{ return; } }else{ return; } request.send(null); } And Index.php: <?php $details = array ( 'itemGuitar' => "<p>Pete Townshend once played this guitar while his own axe was in the shop having bits of drumkit removed from it.</p>", 'itemShades' => "<p>Yoko Ono's sunglasses. While perhaps not valued much by Beatles fans, this pair is rumored to have been licked by John Lennon.</p>", 'itemCowbell' => "<p>Remember the famous \"more cowbell\" skit from Saturday Night Live? Well, this is the actual cowbell.</p>", 'itemHat' => "<p>Michael Jackson's hat, as worn in the \"Billie Jean\" video. Not really rock memorabilia, but it smells better than Slash's tophat.</p>" ); if (isset($_REQUEST['ImageID'])){echo $details[$_REQUEST['ImageID']];} ?> All this code does is that when someone clicks on a thumbnail, a corresponding text description appears on the page. Here is my question. I have tried to bring the getDetails.php code inside Index.php, and modify the getDetails function so that the var url be "Index.php?ImageID="... . When I do that, I get the following problem: the function does not display the snippet of text in the array, as it should. Instead it reproduces the entire code - the webpage, etc - and then at the bottom the expected snippet of text. Why is that?

    Read the article

  • Is it possible to embed Cockburn style textual UML Use Case content in the code base to improve code

    - by fooledbyprimes
    experimenting with Cockburn use cases in code I was writing some complicated UI code. I decided to employ Cockburn use cases with fish,kite,and sea levels (discussed by Martin Fowler in his book 'UML Distilled'). I wrapped Cockburn use cases in static C# objects so that I could test logical conditions against static constants which represented steps in a UI workflow. The idea was that you could read the code and know what it was doing because the wrapped objects and their public contants gave you ENGLISH use cases via namespaces. Also, I was going to use reflection to pump out error messages that included the described use cases. The idea is that the stack trace could include some UI use case steps IN ENGLISH.... It turned out to be a fun way to achieve a mini,psuedo light-weight Domain Language but without having to write a DSL compiler. So my question is whether or not this is a good way to do this? Has anyone out there ever done something similar? c# example snippets follow Assume we have some aspx page which has 3 user controls (with lots of clickable stuff). User must click on stuff in one particular user control (possibly making some kind of selection) and then the UI must visually cue the user that the selection was successful. Now, while that item is selected, the user must browse through a gridview to find an item within one of the other user controls and then select something. This sounds like an easy thing to manage but the code can get ugly. In my case, the user controls all sent event messages which were captured by the main page. This way, the page acted like a central processor of UI events and could keep track of what happens when the user is clicking around. So, in the main aspx page, we capture the first user control's event. using MyCompany.MyApp.Web.UseCases; protected void MyFirstUserControl_SomeUIWorkflowRequestCommingIn(object sender, EventArgs e) { // some code here to respond and make "state" changes or whatever // // blah blah blah // finally we have this (how did we know to call fish level method?? because we knew when we wrote the code to send the event in the user control) UpdateUserInterfaceOnFishLevelUseCaseGoalSuccess(FishLevel.SomeNamedUIWorkflow.SelectedItemForPurchase) } protected void UpdateUserInterfaceOnFishLevelGoalSuccess(FishLevel.SomeNamedUIWorkflow goal) { switch (goal) { case FishLevel.SomeNamedUIWorkflow.NewMasterItemSelected: //call some UI related methods here including methods for the other user controls if necessary.... break; case FishLevel.SomeNamedUIWorkFlow.DrillDownOnDetails: //call some UI related methods here including methods for the other user controls if necessary.... break; case FishLevel.SomeNamedUIWorkFlow.CancelMultiSelect: //call some UI related methods here including methods for the other user controls if necessary.... break; // more cases... } } } //also we have protected void UpdateUserInterfaceOnSeaLevelGoalSuccess(SeaLevel.SomeNamedUIWorkflow goal) { switch (goal) { case SeaLevel.CheckOutWorkflow.ChangedCreditCard: // do stuff // more cases... } } } So, in the MyCompany.MyApp.Web.UseCases namespace we might have code like this: class SeaLevel... class FishLevel... class KiteLevel... The workflow use cases embedded in the classes could be inner classes or static methods or enumerations or whatever gives you the cleanest namespace. I can't remember what I did originally but you get the picture.

    Read the article

  • Google App Engine + Form Validation

    - by Iwona
    Hi, I would like to do google app engine form validation but I dont know how to do it? I tried like this: from google.appengine.ext.db import djangoforms from django import newforms as forms class SurveyForm(forms.Form): occupations_choices = ( ('1', ""), ('2', "Undergraduate student"), ('3', "Postgraduate student (MSc)"), ('4', "Postgraduate student (PhD)"), ('5', "Lab assistant"), ('6', "Technician"), ('7', "Lecturer"), ('8', "Other" ) ) howreach_choices = ( ('1', ""), ('2', "Typed the URL directly"), ('3', "Site is bookmarked"), ('4', "A search engine"), ('5', "A link from another site"), ('6', "From a book"), ('7', "Other") ) boxes_choices = ( ("des", "Website Design"), ("svr", "Web Server Administration"), ("com", "Electronic Commerce"), ("mkt", "Web Marketing/Advertising"), ("edu", "Web-Related Education") ) name = forms.CharField(label='Name', max_length=100, required=True) email = forms.EmailField(label='Your Email Address:') occupations = forms.ChoiceField(choices=occupations_choices, label='What is your occupation?') howreach = forms.ChoiceField(choices=howreach_choices, label='How did you reach this site?') # radio buttons 1-5 rating = forms.ChoiceField(choices=range(1,6), label='What is your occupation?', widget=forms.RadioSelect) boxes = forms.ChoiceField(choices=boxes_choices, label='Are you involved in any of the following? (check all that apply):', widget=forms.CheckboxInput) comment = forms.CharField(widget=forms.Textarea, required=False) And I wanted to display it like this: template_values = { 'url' : url, 'url_linktext' : url_linktext, 'userName' : userName, 'item1' : SurveyForm() } And I have this error message: Traceback (most recent call last): File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp_init_.py", line 515, in call handler.get(*groups) File "C:\Program Files\Google\google_appengine\demos\b00213576\main.py", line 144, in get self.response.out.write(template.render(path, template_values)) File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp\template.py", line 143, in render return t.render(Context(template_dict)) File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp\template.py", line 183, in wrap_render return orig_render(context) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 168, in render return self.nodelist.render(context) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 705, in render bits.append(self.render_node(node, context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 718, in render_node return(node.render(context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template\defaulttags.py", line 209, in render return self.nodelist_true.render(context) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 705, in render bits.append(self.render_node(node, context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 718, in render_node return(node.render(context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 768, in render return self.encode_output(output) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 757, in encode_output return str(output) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\util.py", line 26, in str return self.unicode().encode(settings.DEFAULT_CHARSET) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 73, in unicode return self.as_table() File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 144, in as_table return self._html_output(u'%(label)s%(errors)s%(field)s%(help_text)s', u'%s', '', u'%s', False) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 129, in _html_output output.append(normal_row % {'errors': bf_errors, 'label': label, 'field': unicode(bf), 'help_text': help_text}) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 232, in unicode value = value.str() File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\util.py", line 26, in str return self.unicode().encode(settings.DEFAULT_CHARSET) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\widgets.py", line 246, in unicode return u'\n%s\n' % u'\n'.join([u'%s' % w for w in self]) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\widgets.py", line 238, in iter yield RadioInput(self.name, self.value, self.attrs.copy(), choice, i) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\widgets.py", line 212, in init self.choice_value = smart_unicode(choice[0]) TypeError: 'int' object is unsubscriptable Do You have any idea how I can do this validation in different case? I have tried to do it using this kind of: class ItemUserAnswer(djangoforms.ModelForm): class Meta: model = UserAnswer But I dont know how to add extra labels to this form and it is displayed in one line. Do You have any suggestions? Thanks a lot as it making me crazy why it is still not working:/

    Read the article

  • Hardware/Software inventory open source projects

    - by Dick dastardly
    Dear Stackoverflowers I would like to develop a Network Inventory application that works on any operating system. Reports on every possible resource attacehd to a network. Reports all pertinent details of hardware and software. Thats (and i hate to use the phrase) my "End Game". However I am running before i can crawl here. I have no experience of this type of development, e.g. discovering a computers hardware and software settings. I've spent almost two weeks googling and come up short! :-(. So I am turning to you to ask these questions:- My first step is to find an existing open source project i can incorporate into my own code that extracts the fine grained details i am after, e.g. EVERYTHING there is to know about the hardaware and software on a single machine. Does this project exist? or do i have to develop that first? Have i got to write all this in C? I am guessing getting this information about a computer is going to be easier than for printers, scanners, routers etc... e.g. everything else you would find attached to a network. Once i have access to a single computers details i then need to investigate how i can traverse an entire newtork of printers, scanners, routers, load balancers, switches, firewalls, workstations, servers, storeage devices, laptops, monitors, the list goes on and on One problem i have is i dont have a 1000 machine newtork to play on! Is there any such resource available on theinternet? (is that a silly question?) Anywho, if you dont ask you wont find out! One aspect iam really looking forward to finding out how to travers the entire network, should i be using TCP/IP for this? Whats a good site, blog, usergorup, book for TCP/IP development? How do i go about getting through firewalls? How many questions can i ask in one go? :-) My previous question on this topic ended up with PYTHON being championed as the language/script to go with to develop this application in. Having looked at a few PYTHON examples they all seemed to be related to WINDOWS networks and interrogating Windows Management Instrumentation (WMI). I had the feeling you cant rely on whats in WMI, and even if you can that s no good for UNIX netwrks. Surely there exist common code for extracting hardware and software details from a computer? Why cant i find it on the internet? Pease help? Theres no prizes though :-( Thanks in advance I would like to appologise if i have broken forum rules or not tried hard enough on my own before asking for assistance. I just would like to start moving forward with this as its one of the best projects i have been involved with. I am inspired by the many differnt number of challenges involved and that if i manage to produce a useful application at the end of it it would hopefully be extremely helpful to many people. That sit Thanks in advance DD

    Read the article

  • Covariance and Contravariance in C#

    - by edalorzo
    I will start by saying that I am Java developer learning to program in C#. As such I do comparisons of what I know with what I am learning. I have been playing with C# generics for a few hours now, and I have been able to reproduce the same things I know in Java in C#, with the exception of a couple of examples using covariance and contravariance. The book I am reading is not very good in the subject. I will certainly seek more info on the web, but while I do that, perhaps you can help me find a C# implementation for the following Java code. An example is worth a thousand words, and I was hoping that by looking a good code sample I will be able to assimilate this more rapidly. Covariance In Java I can do something like this: public static double sum(List<? extends Number> numbers) { double summation = 0.0; for(Number number : numbers){ summation += number.doubleValue(); } return summation; } I can use this code as follows: List<Integer> myInts = asList(1,2,3,4,5); List<Double> myDoubles = asList(3.14, 5.5, 78.9); List<Long> myLongs = asList(1L, 2L, 3L); double result = 0.0; result = sum(myInts); result = sum(myDoubles) result = sum(myLongs); Now I did discover that C# supports covariance/contravariance only on interfaces and as long as they have been explicitly declared to do so (out). I think I was not able to reproduce this case, because I could not find a common ancestor of all numbers, but I believe that I could have used IEnumerable to implement such thing if a common ancestor exists. Since IEnumerable is a covariant type. Right? Any thoughts on how to implement the list above? Just point me into the right direction. Is there any common ancestor of all numeric types? Contravariance The contravariance example I tried was the following. In Java I can do this to copy one list into another. public static void copy(List<? extends Number> source, List<? super Number> destiny){ for(Number number : source) { destiny.add(number); } } Then I could use it with contravariant types as follows: List<Object> anything = new ArrayList<Object>(); List<Integer> myInts = asList(1,2,3,4,5); copy(myInts, anything); My basic problem, trying to implement this in C# is that I could not find an interface that was both covariant and contravariant at the same time, as it is case of List in my example above. Maybe it can be done with two different interface in C#. Any thoughts on how to implement this? Thank you very much to everyone for any answers you can contribute. I am pretty sure I will learn a lot from any example you can provide.

    Read the article

  • Looping through siblings of a specific row/setting up function

    - by Matt
    Trying to work through my javascript book I am referencing to learn the language and got stuck on looping through siblings of a specific row. W3schools and W3 didnt have what i was looking for. Below is a function walk-through... It reads: Create the countRecords() function. The purpose of this function is to count the number of visible rows in the data table after the table headings. The total is then displayed in the table cell with the id "records". Add the follow commands to the function: a. Create a object named headRow that points to the table row with the id "titleRow". Create a variable named rowCount, setting its initial value to 0. b. Create a for loop that uses familial references starting with the first sibling of headRow and moving to the next sibling until there are no siblings left. Within the for loop. test whether the node name of the currentnext sibling until there are no sibilings left. Within the for loop test whether the node name of the current node is equal to "TR". If it is, test wheter the value of its display style is equal to an empty text string. If it is (indicating that it is visible in the document) increate the value of the rowCount variable by 1. c. Change the text of the "records" table cell to the value of the rowCount variable. Don't use innerHTML. Create a text node that contains the value of the rowCount variable and assign it to a variable called txt. Create a variable called record to store the reference to the element "records" table cell. d. Insert an if condition that test whether the "records" cell has any child nodes. If it does, replace the replace the text node of the "record" table cell with the created text node (txt). If it doesn't append the text node to the cell. var headRow; // part a var rowCount = 0; //part b this is where I get lost. I know I need to access the id titleRow but unsure how to set my loop up specifically for this headRow = document.getElementById("titleRow"); for(var i=0; i<headrow.length; i++) { if (something is not equal == "TH") { make code happen here } if (is "TR" == ""){ rowCount = +1; } //part c var txt = document.createTextNode(rowCount); var record = document.getElementsById("records") //part d holding off on this part until I get a,b,c figured out. The HTML supporting snippet: <table id="filters"> <tr><th colspan="2">Filter Product List</th></tr> <tr> <td>Records: </td> <td id="records"></td> </tr> <table id="prodTable"> <tr><th colspan="8">Digital Cameras</th></tr> <tr id="titleRow"> <th>Model</th> <th>Manufacturer</th> <th>Resolution</th> <th>Zoom</th> <th>Media</th> <th>Video</th> <th>Microphone</th> </tr> Thanks for the help!

    Read the article

  • background image disappears when position relative used in firefox

    - by toomanyairmiles
    So I'm trying to add a badge to the top right corner of a site I'm doing some work on. z-index works to float the object above the page content but each time i try to use position relative the background image disappears only position absolute shows the image. I don't really want to use absolute as the image needs to be positioned on the right hand side of the sites menu bar not the right hand side of the viewport. Any thoughts or advice appreciated <div class="badge-box"> <a href="http://www.google.com" class="badge">Book Now!</a> </div> <div id="header"> <a href="index.php"><img src="images/pixel.gif" width="378" height="31" alt="Welcome to Gwynfryn Farm Cottages" /></a> </div> <div id="main-menu"> <div> <a href="/">Home</a> <a href="/cottages.php">Our Cottages</a> <a href="/gwynfryn.php">Bed &amp; Breakfast</a> <a href="/rates.php">Price Guide</a> <a href="/llanbedr.php">Location &amp; Local Attractions</a> <a href="/news.php">News &amp; Special Offers</a> <a href="/contact.php">Contact Us</a> </div> </div> .badge-box { width: 1030px; margin-left: auto; margin-right: auto; border: 0px solid red; } .badge { background: url(../images/badge.png) 0px 0px no-repeat; width: 148px; height: 148px; text-indent: -10000px; position: relative; z-index: 999; } #header { width: 960px; height: 40px; margin-left:auto; margin-right:auto; margin-top:20px; padding: 20px 0px 0px 20px; background: #58564f url(../images/header-top-background.png); } #main-menu { width: 980px; margin-left: auto; margin-right: auto; height: 35px; /*background: red;*/ background: #58564f url(../images/header-bottom-background.png); font-family: Georgia, "Times New Roman", Times, serif; } #main-menu div { width: 776px; height: 35px; margin-left: auto; margin-right: auto; background: blue; } #main-menu div a { display: block; float: left; padding: 5px 10px 0px 10px; height: 30px; color: #FFFFFF; font-size: 1.2em; text-align: center; background: green; } #main-menu div a:hover { background-color: #333333; }

    Read the article

  • segmented controls mangled during initial transition animation

    - by dLux
    greetings and salutations folks, i'm relatively new to objective c & iphone programming, so bare with me if i've overlooked something obvious.. i created a simple app to play with the different transition animations, setting up a couple segmented controls and a slider.. (Flip/Curl), (left/right) | (up/down), (EaseInOut/EaseIn/EaseOut/Linear) i created a view controller class, and the super view controller switches between 2 instances of the sub class. as you can see from the following image, the first time switching to the 2nd instance, while the animation is occurring the segmented controls are mangled; i'd guess they haven't had enuff time to draw themselves completely.. http://img689.imageshack.us/img689/2320/mangledbuttonsduringtra.png they're fine once the animation is done, and any subsequent times.. if i specify cache:NO in the setAnimationTransition it helps, but there still seems to be some sort of progressive reveal for the text in the segmented controls; they still don't seem to be pre-rendered or initialized properly.. (and surely there's a way to do this while caching the view being transitioned to, since in this case the view isn't changing and should be cacheable.) i'm building my code based on a couple tutorials from a book, so i updated the didReceiveMemoryWarning to set the instanced view controllers to nil; when i invoke a memory warning in the simulator, i assume it's purging the other view, and it acts like a first transition after loading, the view being transitioned to appears just like the image above.. i guess it can't hurt to include the code (sorry if it's considered spamming), this is basically half of it, with a similar chunk following this in an else statement, for the case of the 2nd side being present, switching back to the 1st..: - (IBAction)switchViews:(id)sender { [UIView beginAnimations:@"Transition Animation" context:nil]; if (self.sideBViewController.view.superview == nil) // sideA is active, sideB is coming { if (self.sideBViewController == nil) { SideAViewController *sBController = [[SideAViewController alloc] initWithNibName:@"SideAViewController" bundle:nil]; self.sideBViewController = sBController; [sBController release]; } [UIView setAnimationDuration:sideAViewController.transitionDurationSlider.value]; if ([sideAViewController.transitionAnimation selectedSegmentIndex] == 0) { // flip: 0 == left, 1 == right if ([sideAViewController.flipDirection selectedSegmentIndex] == 0) [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:YES]; else [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.view cache:YES]; } else { // curl: 0 == up, 1 == down if ([sideAViewController.curlDirection selectedSegmentIndex] == 0) [UIView setAnimationTransition:UIViewAnimationTransitionCurlUp forView:self.view cache:YES]; else [UIView setAnimationTransition:UIViewAnimationTransitionCurlDown forView:self.view cache:YES]; } if ([sideAViewController.animationCurve selectedSegmentIndex] == 0) [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut]; else if ([sideAViewController.animationCurve selectedSegmentIndex] == 1) [UIView setAnimationCurve:UIViewAnimationCurveEaseIn]; else if ([sideAViewController.animationCurve selectedSegmentIndex] == 2) [UIView setAnimationCurve:UIViewAnimationCurveEaseOut]; else if ([sideAViewController.animationCurve selectedSegmentIndex] == 3) [UIView setAnimationCurve:UIViewAnimationCurveLinear]; [sideBViewController viewWillAppear:YES]; [sideAViewController viewWillDisappear:YES]; [sideAViewController.view removeFromSuperview]; [self.view insertSubview:sideBViewController.view atIndex:0]; [sideBViewController viewDidAppear:YES]; [sideAViewController viewDidDisappear:YES]; } any other tips or pointers about writing good clean code is also appreciated, i realize i still have a lot to learn.. thank u for ur time, -- d

    Read the article

  • How can I tell the size of my app during development?

    - by Newbyman
    My programming decissions are directly related to how much room I have left, or worse perhaps how much I need to shave off in order to get up the 10mb limit. I have read that Apple has quietly increased the 3G & Edge download limit from 10mb up to 20mb in preparation for the iPad in April. Either way, my real question is how can I gauge a rough estimate of how large my app will end while I'm still in the development phase? Is the file size of my development folder roughly 1 to 1 ratio? Is the compressed file size of my development a better approximation? My .xcodeproj file is only a couple hundred kB, but the size of my folder is 11.8 MB. I have a .sqlite database, less than 20 small png images and a Settings.Bundle. The rest are unknown Xcode files related to build, build for iphoneOS, simulator etc.... My source code is rather large with around 1000 lines in most of the major controllers, all in all around 48 .h&.m files. But my classes folder inside my development folder is less than 800kb. Digging around inside my Build file, there is lots of iphone simulator files and debugging files which I don't think will contribute to the final product. The Application file states that it is around 2.3 MB. However, this is such a large difference from the 11.8 MB, I have to wonder if this is just another piece of the equation. I have the app on the my device, I'm in the testing phase. Therefore, I though that I would try to see how large the working version was on the device by checking in iTunes, however my development app is visible on the right-hand the application's iphone screen, but no information about the app most importantly its size. I also checked in Organizer, I used the lower portion of the screen-(Applications), found my application and selected the drop down arrow which gave my "Application Data" and a download arrow button to the right to save a file on my desktop, named with the unique AppleID. Inside the folder it had three folders-(documents, library, tmp) the documents had a copy of my .sqlite database, the library a few more files but not anything obvious or of size, and the tmp was empty. All in all the entire folder was only 164kb-which tells me that this is not the right place to find the size either. I understand that the size is considered to be the size of my binary plus all the additional files and images that I have add. Does anyone have a effective way of guaging how large the binary is or the relating the development folder size to what the final App Store application size will end up. I know that questions have been posted with similar aspects, but I could not find any answered post that really described...what files, or how to determine size specifically. I know that this question looks like a book, but I just wanted to be specific in conveying exactly what I'm looking for and the attempts thus far. *Note all files are unzipped and still in regular working Xcode order of a single app with no brought-in builds or referenced projects. I'm sure that this is straight forward, I just don't know where to look?

    Read the article

  • Modern alternatives to Java

    - by Ralph
    I have been a Java developer for 14 years and have written an enterprise-level (~500 kloc) Swing application that uses most of the standard library APIs. Recently, I have become disappointed with the progress that the language has made to "modernize" itself, and am looking for an alternative for ongoing development. I have considered moving to the .NET platform, but I have issues with using something the only runs well in Windows (I know about Mono, but that is still far behind Microsoft). I also plan on buying a new Macbook Pro as soon as Apple releases their new rumored Arrandale-based machines and want to develop in an environment that will feel "at home" in Unix/Linux. I have considered using Python or Ruby, but the standard Java library is arguably the largest of any modern language. In JVM-based languages, I looked at Groovy, but am disappointed with its performance. Rumor has it that with the soon-to-be released JDK7, with its InvokeDynamic instruction, this will improve, but I don't know how much. Groovy is also not truly a functional language, although it provides closures and some of the "functional" features on collections. It does not embrace immutability. I have narrowed my search down to two JVM-based alternatives: Scala and Clojure. Each has its strengths and weaknesses. I am looking for opinions. I am not an expert at either of these languages; I have read 2 1/2 books on Scala and am currently reading Stu Halloway's book on Clojure. Scala is strongly statically typed. I know the dynamic language folks claim that static typing is a crutch for not doing unit testing, but it does provide a mechanism for compile-time location of a whole class of errors. Scala is more concise than Java, but not as much as Clojure. Scala's inter-operation with Java seems to be better than Clojure's, in that most Java operations are easier to do in Scala than in Clojure. For example, I can find no way in Clojure to create a non-static initialization block in a class derived from a Java superclass. For example, I like the Apache commons CLI library for command line argument parsing. In Java and Scala, I can create a new Options object and add Option items to it in an initialization block as follows (Java code): final Options options = new Options() { { addOption(new Option("?", "help", false, "Show this usage information"); // other options } }; I can't figure out how to the same thing in Clojure (except by using (doit...)), although that may reflect my lack of knowledge of the language. Clojure's collections are optimized for immutability. They rarely require copy-on-write semantics. I don't know if Scala's immutable collections are implemented using similar algorithms, but Rich Hickey (Clojure's inventor) goes out of his way to explain how that language's data structures are efficient. Clojure was designed from the beginning for concurrency (as was Scala) and with modern multi-core processors, concurrency takes on more importance, but I occasionally need to write simple non-concurrent utilities, and Scala code probably runs a little faster for these applications since it discourages, but does not prohibit, "simple" mutability. One could argue that one-off utilities do not have to be super-fast, but sometimes they do tasks that take hours or days to complete. I know that there is no right answer to this "question", but I thought I would open it up for discussion. Are there other JVM-based languages that can be used for enterprise level development?

    Read the article

  • TDD - beginner problems and stumbling blocks

    - by Noufal Ibrahim
    While I've written unit tests for most of the code I've done, I only recently got my hands on a copy of TDD by example by Kent Beck. I have always regretted certain design decisions I made since they prevented the application from being 'testable'. I read through the book and while some of it looks alien, I felt that I could manage it and decided to try it out on my current project which is basically a client/server system where the two pieces communicate via. USB. One on the gadget and the other on the host. The application is in Python. I started off and very soon got entangled in a mess of rewrites and tiny tests which I later figured didn't really test anything. I threw away most of them and and now have a working application for which the tests have all coagulated into just 2. Based on my experiences, I have a few questions which I'd like to ask. I gained some information from http://stackoverflow.com/questions/1146218/new-to-tdd-are-there-sample-applications-with-tests-to-show-how-to-do-tdd but have some specific questions which I'd like answers to/discussion on. Kent Beck uses a list which he adds to and strikes out from to guide the development process. How do you make such a list? I initially had a few items like "server should start up", "server should abort if channel is not available" etc. but they got mixed and finally now, it's just something like "client should be able to connect to server" (which subsumed server startup etc.). How do you handle rewrites? I initially selected a half duplex system based on named pipes so that I could develop the application logic on my own machine and then later add the USB communication part. It them moved to become a socket based thing and then moved from using raw sockets to using the Python SocketServer module. Each time things changed, I found that I had to rewrite considerable parts of the tests which was annoying. I'd figured that the tests would be a somewhat invariable guide during my development. They just felt like more code to handle. I needed a client and a server to communicate through the channel to test either side. I could mock one of the sides to test the other but then the whole channel wouldn't be tested and I worry that I'd miss that. This detracted from the whole red/green/refactor rhythm. Is this just lack of experience or am I doing something wrong? The "Fake it till you make it" left me with a lot of messy code that I later spent a lot of time to refactor and clean up. Is this the way things work? At the end of the session, I now have my client and server running with around 3 or 4 unit tests. It took me around a week to do it. I think I could have done it in a day if I were using the unit tests after code way. I fail to see the gain. I'm looking for comments and advice from people who have implemented large non trivial projects completely (or almost completely) using this methodology. It makes sense to me to follow the way after I have something already running and want to add a new feature but doing it from scratch seems to tiresome and not worth the effort. P.S. : Please let me know if this should be community wiki and I'll mark it like that. Update 0 : All the answers were equally helpful. I picked the one I did because it resonated with my experiences the most. Update 1: Practice Practice Practice!

    Read the article

  • What broke in this Javascript 1.2 snippet?

    - by Rob Kelley
    A friend has pointed me to his old website and says "the submit form just stopped working a while ago. I'm sure it's something simple." The form asks a child for a certain word from a book, and based on the answer, it should redirect the child to a success page or a failure page. It's using Javascript 1.2, circa 2001. You can see this form in in-action at: http://www.secrethidingplaces.com/login1.html Any idea why it's failing? The HTML does this: <script src="password.js" type="text/javascript" language="JavaScript1.2"> </script> <script type="text/javascript" language="JavaScript1.2"> <!-- function showRightPage () { return window.location.href = "extra.html" ; } function showWrongPage () { return window.location.href = "sorry2.html" ; } //--> </script> and then this: document.write ( '<form name="questionForm" action="javascript:checkAnswer()" method="post">' ) ; ... document.write ( '<input type="text" name="userAnswer" value="" size="90">' ) ; document.write ( '<INPUT TYPE="image" NAME="submit" SRC="stock/btn_send.gif" width="121" height="41" BORDER="0" ALT="submit">' ) ; document.write ( '\</p>' ) ; document.write ( '\</form>' ) ; I'm assuming there's something ugly in CheckAnswer from ./password.js . I can hack the form to bypass that javascript and go straight to the success page: document.write ( '<form name="questionForm" action="extra.html" method="post">' ) ; but I'd like to help my friend get his kids site working again. The CheckAnswer function is below. Is something going wrong in here? function checkAnswer () { currentAnswer = answersArray [ choiceNumber ] ; if (agt.indexOf("msie") != -1) { rawAnswer = document.questionForm.userAnswer.value ; } else { rawAnswer = document.callThis.document.questionForm.userAnswer.value ; } lcAnswer = rawAnswer.toLowerCase ( ) ; includedAnswer = lcAnswer.indexOf ( "currentAnswer" ) ; zadaAnswer = lcAnswer.indexOf ( "zada" ) ; brendanAnswer = lcAnswer.indexOf ( "brendan" ) ; nineAnswer = lcAnswer.indexOf ( "nine" ) ; thirtyAnswer = lcAnswer.indexOf ( "thirty" ) ; if ( choiceNumber == 0 ) { if ( includedAnswer == -1 && zadaAnswer == -1 && brendanAnswer == -1 ) { checked = "wrong" ; } } if ( choiceNumber == 8 ) { if ( includedAnswer == -1 && zadaAnswer == -1 && nineAnswer == -1 ) { checked = "wrong" ; } } if ( choiceNumber == 16 ) { if ( includedAnswer == -1 && zadaAnswer == -1 && thirtyAnswer == -1 ) { checked = "wrong" ; } } if ( choiceNumber != 0 && choiceNumber != 8 && choiceNumber != 16 ) { if ( includedAnswer == -1 && zadaAnswer == -1 ) { checked = "wrong" ; } } if ( checked == "wrong" ) { showWrongPage () ; } else { showRightPage () ; } } Thanks!

    Read the article

  • How to find specific value of the node in xml file

    - by user2735149
    I am making windows phone 8 app based the webservices. This is my xml code: - <response> <timestamp>2013-10-31T08:30:56Z</timestamp> <resultsOffset>0</resultsOffset> <status>success</status> <resultsLimit>8</resultsLimit> <resultsCount>38</resultsCount> - <headlines> - <headlinesItem> <headline>City edge past Toon</headline> <keywords /> <lastModified>2013-10-30T23:45:22Z</lastModified> <audio /> <premium>false</premium> + <links> - <api> - <news> <href>http://api.espn.com/v1/sports/news/1600444?region=GB</href> </news> </api> - <web> <href>http://espnfc.com/uk/en/report/381799/city-edge-toon?ex_cid=espnapi_public</href> </web> - <mobile> <href>http://m.espn.go.com/soccer/gamecast?gameId=381799&lang=EN&ex_cid=espnapi_public</href> </mobile> </links> <type>snReport</type> <related /> <id>1600444</id> <story>Alvardo Negredo and Edin Dzeko struck in extra-time to book Manchester City's place in the last eight of the Capital One Cup, while Costel Pantilimon kept a clean sheet in the 2-0 win to keep the pressure on Joe Hart. </story> <linkText>Newcastle 0-2 Man City</linkText> - <images> - <imagesItem> <height>360</height> <alt>Man City celebrate after Edin Dzeko scored their second extra-time goal at Newcastle.</alt> <width>640</width> <name>Man City celeb Edin Dzeko goal v nufc 20131030 [640x360]</name> <caption>Man City celebrate after Edin Dzeko scored their second extra-time goal at Newcastle.</caption> <type>inline</type> <url>http://espnfc.com/design05/images/2013/1030/mancitycelebedindzekogoalvnufc20131030_640x360.jpg</url> </imagesItem> </images> Code behind: myData = XDocument.Parse(e.Result, LoadOptions.None); var data = myData.Descendants("headlines").FirstOrDefault(); var data1 = from query in myData.Descendants("headlinesItem") select new UpdataNews { News = (string)query.Element("headline").Value, Desc = (string)query.Element("description"), Newsurl = (string)query.Element("links").Element("mobile").Element("href"), Imageurl=(string)query.Element("images").Element("imagesItem").Element("url").Value, }; lstShow.ItemsSource = data1; I am trying to get value from xml tags and assign them to News,Desc, etc. Everything works fine except Imageurl, it shows NullException. I tried same method for Imageurl, i dont know whats going wrong. Help..

    Read the article

  • Resolving a Forward Declaration Issue Involving a State Machine in C++

    - by hypersonicninja
    I've recently returned to C++ development after a hiatus, and have a question regarding implementation of the State Design Pattern. I'm using the vanilla pattern, exactly as per the GoF book. My problem is that the state machine itself is based on some hardware used as part of an embedded system - so the design is fixed and can't be changed. This results in a circular dependency between two of the states (in particular), and I'm trying to resolve this. Here's the simplified code (note that I tried to resolve this by using headers as usual but still had problems - I've omitted them in this code snippet): #include <iostream> #include <memory> using namespace std; class Context { public: friend class State; Context() { } private: State* m_state; }; class State { public: State() { } virtual void Trigger1() = 0; virtual void Trigger2() = 0; }; class LLT : public State { public: LLT() { } void Trigger1() { new DH(); } void Trigger2() { new DL(); } }; class ALL : public State { public: ALL() { } void Trigger1() { new LLT(); } void Trigger2() { new DH(); } }; // DL needs to 'know' about DH. class DL : public State { public: DL() { } void Trigger1() { new ALL(); } void Trigger2() { new DH(); } }; class HLT : public State { public: HLT() { } void Trigger1() { new DH(); } void Trigger2() { new DL(); } }; class AHL : public State { public: AHL() { } void Trigger1() { new DH(); } void Trigger2() { new HLT(); } }; // DH needs to 'know' about DL. class DH : public State { public: DH () { } void Trigger1() { new AHL(); } void Trigger2() { new DL(); } }; int main() { auto_ptr<LLT> llt (new LLT); auto_ptr<ALL> all (new ALL); auto_ptr<DL> dl (new DL); auto_ptr<HLT> hlt (new HLT); auto_ptr<AHL> ahl (new AHL); auto_ptr<DH> dh (new DH); return 0; } The problem is basically that in the State Pattern, state transitions are made by invoking the the ChangeState method in the Context class, which invokes the constructor of the next state. Because of the circular dependency, I can't invoke the constructor because it's not possible to pre-define both of the constructors of the 'problem' states. I had a look at this article, and the template method which seemed to be the ideal solution - but it doesn't compile and my knowledge of templates is a rather limited... The other idea I had is to try and introduce a Helper class to the subclassed states, via multiple inheritance, to see if it's possible to specify the base class's constructor and have a reference to the state subclasse's constructor. But I think that was rather ambitious... Finally, would a direct implmentation of the Factory Method Design Pattern be the best way to resolve the entire problem?

    Read the article

  • Is there a library available which easily can record and replay results of API calls?

    - by Billy ONeal
    I'm working on writing various things that call relatively complicated Win32 API functions. Here's an example: //Encapsulates calling NtQuerySystemInformation buffer management. WindowsApi::AutoArray NtDll::NtQuerySystemInformation( SystemInformationClass toGet ) const { AutoArray result; ULONG allocationSize = 1024; ULONG previousSize; NTSTATUS errorCheck; do { previousSize = allocationSize; result.Allocate(allocationSize); errorCheck = WinQuerySystemInformation(toGet, result.GetAs<void>(), allocationSize, &allocationSize); if (allocationSize <= previousSize) allocationSize = previousSize * 2; } while (errorCheck == 0xC0000004L); if (errorCheck != 0) { THROW_MANUAL_WINDOWS_ERROR(WinRtlNtStatusToDosError(errorCheck)); } return result; } //Client of the above. ProcessSnapshot::ProcessSnapshot() { using Dll::NtDll; NtDll ntdll; AutoArray systemInfoBuffer = ntdll.NtQuerySystemInformation( NtDll::SystemProcessInformation); BYTE * currentPtr = systemInfoBuffer.GetAs<BYTE>(); //Loop through the results, creating Process objects. SYSTEM_PROCESSES * asSysInfo; do { // Loop book keeping asSysInfo = reinterpret_cast<SYSTEM_PROCESSES *>(currentPtr); currentPtr += asSysInfo->NextEntryDelta; //Create the process for the current iteration and fill it with data. std::auto_ptr<ProcImpl> currentProc(ProcFactory( static_cast<unsigned __int32>(asSysInfo->ProcessId), this)); NormalProcess* nptr = dynamic_cast<NormalProcess*>(currentProc.get()); if (nptr) { nptr->SetProcessName(asSysInfo->ProcessName); } // Populate process threads for(ULONG idx = 0; idx < asSysInfo->ThreadCount; ++idx) { SYSTEM_THREADS& sysThread = asSysInfo->Threads[idx]; Thread thread( currentProc.get(), static_cast<unsigned __int32>(sysThread.ClientId.UniqueThread), sysThread.StartAddress); currentProc->AddThread(thread); } processes.push_back(currentProc); } while(asSysInfo->NextEntryDelta != 0); } My problem is in mocking out the NtDll::NtQuerySystemInformation method -- namely, that the data structure returned is complicated (Well, here it's actually relatively simple but it can be complicated), and writing a test which builds the data structure like the API call does can take 5-6 times as long as writing the code that uses the API. What I'd like to do is take a call to the API, and record it somehow, so that I can return that recorded value to the code under test without actually calling the API. The returned structures cannot simply be memcpy'd, because they often contain inner pointers (pointers to other locations in the same buffer). The library in question would need to check for these kinds of things, and be able to restore pointer values to a similar buffer upon replay. (i.e. check each pointer sized value if it could be interpreted as a pointer within the buffer, change that to an offset, and remember to change it back to a pointer on replay -- a false positive rate here is acceptable) Is there anything out there that does anything like this?

    Read the article

  • Merge Sort issue when removing the array copy step

    - by Ime Prezime
    I've been having an issue that I couldn't debug for quite some time. I am trying to implement a MergeSort algorithm with no additional steps of array copying by following Robert Sedgewick's algorithm in "Algorithm's in C++" book. Short description of the algorithm: The recursive program is set up to sort b, leaving results in a. Thus, the recursive calls are written to leave their result in b, and we use the basic merge program to merge those files from b into a. In this way, all the data movement is done during the course of the merges. The problem is that I cannot find any logical errors but the sorting isn't done properly. Data gets overwritten somewhere and I cannot determine what logical error causes this. The data is sorted when the program is finished but it is not the same data any more. For example, Input array: { A, Z, W, B, G, C } produces the array: { A, G, W, W, Z, Z }. I can obviously see that it must be a logical error somewhere, but I have been trying to debug this for a pretty long time and I think a fresh set of eyes could maybe see what I'm missing cause I really can't find anything wrong. My code: static const int M = 5; void insertion(char** a, int l, int r) { int i,j; char * temp; for (i = 1; i < r + 1; i++) { temp = a[i]; j = i; while (j > 0 && strcmp(a[j-1], temp) > 0) { a[j] = a[j-1]; j = j - 1; } a[j] = temp; } } //merging a and b into c void merge(char ** c,char ** a, int N, char ** b, int M) { for (int i = 0, j = 0, k = 0; k < N+M; k++) { if (i == N) { c[k] = b[j++]; continue; } if (j == M) { c[k] = a[i++]; continue; } c[k] = strcmp(a[i], b[j]) < 0 ? a[i++] : b[j++]; } } void mergesortAux(char ** a, char ** b, int l, int r) { if(r - l <= M) { insertion(a, l, r); return; } int m = (l + r)/2; mergesortAux(b, a, l, m); //merge sort left mergesortAux(b, a, m+1, r); //merge sort right merge(a+l, b+l, m-l+1, b+m+1, r-m); //merge } void mergesort(char ** a,int l, int r, int size) { static char ** aux = (char**)malloc(size * sizeof(char*)); for(int i = l; i < size; i++) aux[i] = a[i]; mergesortAux(a, aux, l, r); free(aux); }

    Read the article

  • Having some trouble in my pagation code(PHP)

    - by user300371
    My table is posting and in that table, it shows all the posting people put in. I am trying to make page navigation links at the bottom of the posts. the function generateenter code here_page_links does all the work. The code seem to be only showing the "<-" and "-" and not the link numbers. I think the function is only reading the $_GET['posting'] ==1. (this code is from the Oreilly PHP/MySQL book. I am using it as practice) function generate_page_links($cur_page, $num_pages) { $page_links = ''; // If this page is not the first page, generate the "previous" link if ($cur_page > 1) { //cur_page is just a number that is gotten from the url. $page_links .= '<a href="' . $_SERVER['PHP_SELF'] . '?page=' . ($cur_page - 1) . '"><--</a> '; } else { $page_links .= '<- '; } // Loop through the pages generating the page number links for ($i = 1; $i <= $num_pages; $i++) { if ($cur_page == $i) { $page_links .= ' ' . $i; } else { $page_links .= ' <a href="' . $_SERVER['PHP_SELF'] . '?usersearch=' . $user_search . '&sort=' . $sort . '&page=' . $i . '"> ' . $i . '</a>'; } } // If this page is not the last page, generate the "next" link if ($cur_page < $num_pages) { $page_links .= ' <a href="' . $_SERVER['PHP_SELF'] . '?usersearch=' . $user_search . '&sort=' . $sort . '&page=' . ($cur_page + 1) . '">-></a>'; } if ($cur_page == $num_pages){ //the last page $page_links .= ' ->'; } return $page_links; //need to return this variable in the function } // Calculate pagination information $cur_page = isset($_GET['page']) ? $_GET['page'] : 1; $results_per_page = 3; // number of results per page $skip = (($cur_page - 1) * $results_per_page); $query = "SELECT * FROM posting ORDER BY date_added DESC"; $data = mysqli_query($dbc, $query); $total = mysqli_num_rows($data); $num_pages = ceil($total / $results_per_page); //Query again to get just the subset of results $query = $query . " LIMIT $skip, $results_per_page"; $result = mysqli_query($dbc, $query); echo '<table>'; echo '<tr><td><b>Title</b></td><td><b>Date Posted</b></td></tr>'; while ($row = mysqli_fetch_array($result)) { echo '<tr><td><a href="ad.php? posting_id='.$row['posting_id'].' ">'.$row['title'].'</a></td>'; echo '<td>'.$row['date_added'].'</td>'; //echo '<td>'.$row['name'].'</td></tr>'; } echo '</table>'; // Generate navigational page links if we have more than one page if ($num_pages > 1) { echo generate_page_links($user_search, $sort, $cur_page, $num_pages); }

    Read the article

  • Trying to packetize TCP with non-blocking IO is hard! Am I doing something wrong?

    - by Ricket
    Oh how I wish TCP was packet-based like UDP is! But alas, that's not the case, so I'm trying to implement my own packet layer. Here's the chain of events so far (ignoring writing packets) Oh, and my Packets are very simply structured: two unsigned bytes for length, and then byte[length] data. (I can't imagine if they were any more complex, I'd be up to my ears in if statements!) Server is in an infinite loop, accepting connections and adding them to a list of Connections. PacketGatherer (another thread) uses a Selector to figure out which Connection.SocketChannels are ready for reading. It loops over the results and tells each Connection to read(). Each Connection has a partial IncomingPacket and a list of Packets which have been fully read and are waiting to be processed. On read(): Tell the partial IncomingPacket to read more data. (IncomingPacket.readData below) If it's done reading (IncomingPacket.complete()), make a Packet from it and stick the Packet into the list waiting to be processed and then replace it with a new IncomingPacket. There are a couple problems with this. First, only one packet is being read at a time. If the IncomingPacket needs only one more byte, then only one byte is read this pass. This can of course be fixed with a loop but it starts to get sorta complicated and I wonder if there is a better overall way. Second, the logic in IncomingPacket is a little bit crazy, to be able to read the two bytes for the length and then read the actual data. Here is the code, boiled down for quick & easy reading: int readBytes; // number of total bytes read so far byte length1, length2; // each byte in an unsigned short int (see getLength()) public int getLength() { // will be inaccurate if readBytes < 2 return (int)(length1 << 8 | length2); } public void readData(SocketChannel c) { if (readBytes < 2) { // we don't yet know the length of the actual data ByteBuffer lengthBuffer = ByteBuffer.allocate(2 - readBytes); numBytesRead = c.read(lengthBuffer); if(readBytes == 0) { if(numBytesRead >= 1) length1 = lengthBuffer.get(); if(numBytesRead == 2) length2 = lengthBuffer.get(); } else if(readBytes == 1) { if(numBytesRead == 1) length2 = lengthBuffer.get(); } readBytes += numBytesRead; } if(readBytes >= 2) { // then we know we have the entire length variable // lazily-instantiate data buffers based on getLength() // read into data buffers, increment readBytes // (does not read more than the amount of this packet, so it does not // need to handle overflow into the next packet's data) } } public boolean complete() { return (readBytes > 2 && readBytes == getLength()+2); } Basically I need feedback on my code. Please suggest any improvements. Even overhauling my entire system would be okay, if you have suggestions for how better to implement the whole thing. Book recommendations are welcome too; I love books. I just get the feeling that something isn't quite right.

    Read the article

  • CakePHP access indirectly related model - beginner's question

    - by user325077
    Hi everyone, I am writing a CakePHP application to log the work I do for various clients, but after trying for days I seem unable to get it to do what I want. I have read most of the book CakePHP's website. and googled for all I'm worth, so I presume I am missing something obvious! Every 'log item' belongs to a 'sub-project, which in turn belongs to a 'project', which in turn belongs to a 'sub-client' which finally belongs to a client. These are the 5 MySQL tables I am using: mysql> DESCRIBE log_items; +-----------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-----------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | date | date | NO | | NULL | | | time | time | NO | | NULL | | | time_spent | int(11) | NO | | NULL | | | sub_projects_id | int(11) | NO | MUL | NULL | | | title | varchar(100) | NO | | NULL | | | description | text | YES | | NULL | | | created | datetime | YES | | NULL | | | modified | datetime | YES | | NULL | | +-----------------+--------------+------+-----+---------+----------------+ mysql> DESCRIBE sub_projects; +-------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | varchar(100) | NO | | NULL | | | projects_id | int(11) | NO | MUL | NULL | | | created | datetime | YES | | NULL | | | modified | datetime | YES | | NULL | | +-------------+--------------+------+-----+---------+----------------+ mysql> DESCRIBE projects; +----------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | varchar(100) | NO | | NULL | | | sub_clients_id | int(11) | NO | MUL | NULL | | | created | datetime | YES | | NULL | | | modified | datetime | YES | | NULL | | +----------------+--------------+------+-----+---------+----------------+ mysql> DESCRIBE sub_clients; +------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | varchar(100) | NO | | NULL | | | clients_id | int(11) | NO | MUL | NULL | | | created | datetime | YES | | NULL | | | modified | datetime | YES | | NULL | | +------------+--------------+------+-----+---------+----------------+ mysql> DESCRIBE clients; +----------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | varchar(100) | NO | | NULL | | | created | datetime | YES | | NULL | | | modified | datetime | YES | | NULL | | +----------+--------------+------+-----+---------+----------------+ I have set up the following associations in CakePHP: LogItem belongsTo SubProjects SubProject belongsTo Projects Project belongsTo SubClients SubClient belongsTo Clients Client hasMany SubClients SubClient hasMany Projects Project hasMany SubProjects SubProject hasMany LogItems Using 'cake bake' I have created the models, controllers (index, view add, edit and delete) and views, and things seem to function - as in I am able to perform simple CRUD operations successfully. The Question When editing a 'log item' at www.mydomain/log_items/edit I am presented with the view you would all suspect; namely the columns of the log_items table with the appropriate textfields/select boxes etc. I would also like to incorporate select boxes to choose the client, sub-client, project and sub-project in the 'log_items' edit view. Ideally the 'sub-client' select box should populate itself depending upon the 'client' chosen, the 'project' select box should also populate itself depending on the 'sub-client' selected etc, etc. I guess the way to go about populating the select boxes with relevant options is Ajax, but I am unsure of how to go about actually accessing a model from the child view of a indirectly related model, for example how to create a 'sub-client' select box in the 'log_items' edit view. I have have found this example: http://forum.phpsitesolutions.com/php-frameworks/cakephp/ajax-cakephp-dynamically-populate-html-select-dropdown-box-t29.html where someone achieves something similar for US states, counties and cities. However, I noticed in the database schema - which is downloadable from the site above link - that the database tables don't have any foreign keys, so now I'm wondering if I'm going about things in the correct manner. Any pointers and advice would be very much appreciated. Kind regards, Chris

    Read the article

  • Why ((Integer) weightModel.getObject()).intValue(); throws exception

    - by yakup
    I am learning Wicket by "Enjoying Web Development with Wicket" book. And in an example: int weight = ((Integer) weightModel.getObject()).intValue(); is used. When I click Submit button it throws exception. But after changed the code to: int weight=Integer.parseInt( (String) weightModel.getObject()); It works fine. What is the reason for throwing the exception? The full code: GetRequest.java package myapp.postage; import java.util.HashMap; import java.util.Map; import org.apache.wicket.markup.html.WebPage; import org.apache.wicket.markup.html.form.Form; import org.apache.wicket.markup.html.form.TextField; import org.apache.wicket.model.Model; @SuppressWarnings("unchecked") public class GetRequest extends WebPage { private Model weightModel=new Model(); private Model patronCodeModel=new Model(); private Map patronCodeToDiscount; public GetRequest(){ patronCodeToDiscount=new HashMap(); patronCodeToDiscount.put("p1", new Integer(90)); patronCodeToDiscount.put("p2", new Integer(95)); Form form=new Form("form"){ @Override protected void onSubmit(){ int weight = ((Integer) weightModel.getObject()).intValue(); Integer discount=(Integer)patronCodeToDiscount.get(patronCodeModel.getObject()); int postagePerKg=10; int postage=weight*postagePerKg; if(discount!=null){ postage=postage*discount.intValue()/100; } ShowPostage showPostage=new ShowPostage(postage); setResponsePage(showPostage); } }; TextField weight=new TextField("weight",weightModel); form.add(weight); TextField patronCode=new TextField("patronCode",patronCodeModel); form.add(patronCode); add(form); } } The html file GetRequest.html: <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <form wicket:id="form"> <table> <tr> <td>Weight</td> <td><input type="text" wicket:id="weight"/></td> </tr> <tr> <td>Patron code:</td> <td><input type="text" wicket:id="patronCode"/></td> </tr> <tr> <td></td> <td><input type="submit"/></td> </tr> </table> </form> </html>

    Read the article

< Previous Page | 222 223 224 225 226 227 228 229 230 231 232  | Next Page >