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  • jquery draggable/droppable issue

    - by Scarface
    Hey guys I have a drag and drop function that does not fully work. What I want to do is be able to drag and drop a picture into a div and have that picture pop up in the div. I have a list of 2 pictures right now, so I have the following function echoed for each picture. Both pictures are draggable and droppable, but the first one is the only one that appears in the div, regardless of which picture gets dragged in. I am not sure what is wrong because the jquery function seems to be unique to each picture. If any one has any suggestions I would appreciate it greatly. while ($row = mysql_fetch_assoc($query)) { $image=htmlentities($row['image']); //image name $uniqid=uniqid(); //unique id for jquery functions $dirname = "usercontent/$user/images/$image"; echo "<img id=\"$uniqid\" src=\"$dirname\" width=\"75\" height=\"75\"/>"; echo "<script> $(function() { $(\"#$uniqid\").draggable({ scroll: true, scrollSensitivity: 10, scrollSpeed: 10, revert: true, helper: 'clone', cursorAt: { cursor: 'move', top: 27, left: 27 } }); $(\"#droppable2, #droppable-background , #droppable2-innerer\").droppable({ greedy: true, activeClass: 'ui-state-hover', hoverClass: 'ui-state-active', drop: function(event, ui) { $(this).addClass('ui-state-highlight').find('> p').html('Dropped!'); $('#droppable-background').css(\"background-image\",\"url($dirname)\"); } }); }); </script>"; }

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  • re.sub emptying list

    - by jmau5
    def process_dialect_translation_rules(): # Read in lines from the text file specified in sys.argv[1], stripping away # excess whitespace and discarding comments (lines that start with '##'). f_lines = [line.strip() for line in open(sys.argv[1], 'r').readlines()] f_lines = filter(lambda line: not re.match(r'##', line), f_lines) # Remove any occurances of the pattern '\s*<=>\s*'. This leaves us with a # list of lists. Each 2nd level list has two elements: the value to be # translated from and the value to be translated to. Use the sub function # from the re module to get rid of those pesky asterisks. f_lines = [re.split(r'\s*<=>\s*', line) for line in f_lines] f_lines = [re.sub(r'"', '', elem) for elem in line for line in f_lines] This function should take the lines from a file and perform some operations on the lines, such as removing any lines that begin with ##. Another operation that I wish to perform is to remove the quotation marks around the words in the line. However, when the final line of this script runs, f_lines becomes an empty lines. What happened? Requested lines of original file: ## English-Geek Reversible Translation File #1 ## (Moderate Geek) ## Created by Todd WAreham, October 2009 "TV show" <=> "STAR TREK" "food" <=> "pizza" "drink" <=> "Red Bull" "computer" <=> "TRS 80" "girlfriend" <=> "significant other"

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  • Starting an STA thread, but with parameters to the final function

    - by DRapp
    I'm a bit weak on how some delegates behave, such as passing a method as the parameter to be invoked. While trying to do some NUnit test scripts, I have something that I need to run many test with. Each of these tests requires a GUI created and thus the need for an STA thread. So, I have something like public class MyTest { // the Delegate "ThreadStart" is part of the System.Threading namespace and is defined as // public delegate void ThreadStart(); protected void Start_STA_Thread(ThreadStart whichMethod) { Thread thread = new Thread(whichMethod); thread.SetApartmentState(ApartmentState.STA); //Set the thread to STA thread.Start(); thread.Join(); } [Test] public void Test101() { // Since the thread issues an INVOKE of a method, I'm having it call the // corresponding "FromSTAThread" method, such as Start_STA_Thread( Test101FromSTAThread ); } protected void Test101FromSTAThread() { MySTA_RequiredClass oTmp = new MySTA_RequiredClass(); Assert.IsTrue( oTmp.DoSomething() ); } } This part all works fine... Now the next step. I now have a different set of tests that ALSO require an STA thread. However, each "thing" I need to do requires two parameters... both strings (for this case). How do I go about declaring proper delegate so I can pass in the method I need to invoke, AND the two string parameters in one shot... I may have 20+ tests to run with in this pattern and may have future of other similar tests with different parameter counts and types of parameters too. Thanks.

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  • Help regarding database and logic layer for my ASP.NET MVC application

    - by Ismail S
    I'm going to start a new project which is going to be small initially but may grow to big over the years. I'm strongly convinced that I'm going to use ASP.NET MVC with jQuery for UI. I want to go for MySQL as database for some reasons but worried on few things. I've a good years of experience working on SQL Server databases and on one project I've had a bad experience creating and managing stored procedures on MySQL database. I'm totally new to Linq but I see that it is easier to use once you are familiar with it. First thing is that accessing data should be easy. So I thought I should use MySQL to Linq but somewhere I read that it is not directly supported but MySQL .NET connector adds support for EntityFramework. I don't know what are the pros and cons of it. I would love if I can implement repository pattern. Will it be possible if I use Entity Framework? I'm not clear on how I should go about all this or I should just forget every thing and directly use SQL to Linq on SQL Server. I'm also concerned about the performance. Someone told me that if we use Entity framework it fetches lot of data and then filter it. Is that right?

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  • Automating Excel 2010 using F#

    - by Clive Norman
    I have been searching for a FAQ to tell me how to open a Excel Workbook/Worksheet and also how to Save the File once I have finished. I notice that in most FAQ and all the books I have purchased on F# one is show how to create a new Workbook/Worksheet but is never shown how to either open or Save it. Being a newbie to F# I would very much appreciate it if anyone could kindly provide me with either an answer or perhaps a few pointers? Update As for why F# and not C# or VB? I am pleased to say that inspite of being a newbie (with the exception of Forth, VBA & Excel 2003, 2007 & 2010 and Visual Basic) I can do this in both VB, VBA & C# and since I've been retired on medical grounds, with plenty of time unfortunately on my hands, I like to continually set myself challenges to keep my little grey cells active and being a sucker for trying new languages....well! F# is now an intergral part of Visual Studio 2010 so I thought - why not. Consider this - if we are not willing to use or at least try a new languages - I would always be wonder if I might have prefer it to VBA, VB, C# ..... and if you look at it from another point of view, if no one is going to use it - why create it in the first place? I suppose you can say if cave men hadn't experimented and made fire by rubbing two sticks together - where would we be now and would matches have been invented? Although an complete answer would be good, I prefer a few pointers, to keep my challenge going. And lastly but not least - thank you for taking the trouble to respond!

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  • How to get multiple html() strings in jQuery

    - by Bryan
    I'm pretty new to jQuery... so far I'm impressed. But I encountered a situation today that is giving me trouble. I want to use .html() to get some raw text and use that in a selector, but that function only returns the first element. In the following structure, how can I get ALL of the "toggle_containerLG" divs to show when I click on the trigger "Some Header"? <h6 class="trigger active">Some Header</h6> <ul> <li><a href="#" class="trigger">Title One</a></li> <li><a href="#" class="trigger">Title Two</a></li> <li><a href="#" class="trigger">Title Three</a></li> </ul> <div class="toggle_containerLG" id='Title_One'></div> <!-- show these! --> <div class="toggle_containerLG" id='Title_Two'></div> <div class="toggle_containerLG" id='Title_Three'></div> <div class="toggle_containerLG" id='Title_Four'></div> <!-- not this one! --> I can't use $(".toggle_containerLG") because there are others I don't want to expand... I just want the ones listed under "Some Header". Seems like there should be an easy way to do it... and I'm just missing it because I don't know jQuery very well.

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  • accordion tab open at different times

    - by user3279193
    I am using an asp classic and on the page I have a J-Query accordion. I want one tab to be open if the value that the asp prints out is greater than zero, if not , I want them all to be closed, this is an example of what I've got: J-Query: $(function() { $( "#accordion" ).accordion({ heightStyle: "content", collapsible: true, active: false }); }); HTML/ASP: <div id="accordion"> <h3>Tab1</h3> <div> <p>Hello World</p> </div> <h3>Tab2</h3> <div> <p>Hello World</p> </div> <h3>Tab3</h3> <div> <p>Hello World</p> </div> <h3>Results (<%=number%>)</h3> <!--if number > 0 then open tab else close all tabs--> <div> <p>Hello World</p> </div> </div>

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  • Do I need to write a trigger for such a simple constraint?

    - by Paul Hanbury
    I really had a hard time knowing what words to put into the title of my question, as I am not especially sure if there is a database pattern related to my problem. I will try to simplify matters as much as possible to get directly to the heart of the issue. Suppose I have some tables. The first one is a list of widget types: create table widget_types ( widget_type_id number(7,0) primary key, description varchar2(50) ); The next one contains icons: create table icons ( icon_id number(7,0) primary key, picture blob ); Even though the users get to select their preferred widget, there is a predefined subset of widgets that they can choose from for each widget type. create table icon_associations ( widget_type_id number(7,0) references widget_types, icon_id number(7,0) references icons, primary key (widget_type_id, icon_id) ); create table icon_prefs ( user_id number(7,0) references users, widget_type_id number(7,0), icon_id number(7,0), primary key (user_id, widget_type_id), foreign key (widget_type_id, icon_id) references icon_associations ); Pretty simple so far. Let us now assume that if we are displaying an icon to a user who has not set up his preferences, we choose one of the appropriate images associated with the current widget. I'd like to specify the preferred icon to display in such a case, and here's where I run into my problem: alter table icon_associations add ( is_preferred char(1) check( is_preferred in ('y','n') ) ) ; I do not see how I can enforce that for each widget_type there is one, and only one, row having is_preferred set to 'y'. I know that in MySQL, I am able to write a subquery in my check constraint to quickly resolve this issue. This is not possible with Oracle. Is my mistake that this column has no business being in the icon_associations table? If not where should it go? Is this a case where, in Oracle, the constraint can only be handled with a trigger? I ask only because I'd like to go the constraint route if at all possible. Thanks so much for your help, Paul

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  • Java abstract visitor - guarantueed to succeed? If so, why?

    - by disown
    I was dealing with hibernate, trying to figure out the run-time class behind proxied instances by using the visitor pattern. I then came up with an AbstractVisitable approach, but I wonder if it will always produce correct results. Consider the following code: interface Visitable { public void accept(Visitor v); } interface Visitor { public void visit(Visitable visitorHost); } abstract class AbstractVisitable implements Visitable { @Override public void accept(Visitor v) { v.visit(this); } } class ConcreteVisitable extends AbstractVisitable { public static void main(String[] args) { final Visitable visitable = new ConcreteVisitable(); final Visitable proxyVisitable = (Visitable) Proxy.newProxyInstance( Thread.currentThread().getContextClassLoader(), new Class<?>[] { Visitable.class }, new InvocationHandler() { @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { return method.invoke(visitable, args); } }); proxyVisitable.accept(new Visitor() { @Override public void visit(Visitable visitorHost) { System.out.println(visitorHost.getClass()); } }); } } This makes a ConcreteVisitable which inherits the accept method from AbstractVisitable. In c++, I would consider this risky, since this in AbstractVisitable could be referencing to AbstractVisitable::this, and not ConcreteVisitable::this. I was worried that the code under certain circumstances would print class AbstractVisible. Yet the code above outputs class ConcreteVisitable, even though I hid the real type behind a dynamic proxy (the most difficult case I could come up with). Is the abstract visitor approach above guaranteed to work, or are there some pitfalls with this approach? What guarantees are given in Java with respect to the this pointer?

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  • regexp target last main li in list

    - by veilig
    I need to target the starting tag of the last top level LI in a list that may or may-not contain sublists in various positions - without using CSS or Javascript. Is there a simple/elegant regexp that can help with this? I'm no guru w/ them, but it appears the need for greedy/non-greedy selectors when I'm selecting all the middle text (.*) / (.+) changes as nested lists are added and moved around in the list - and this is throwing me off. $pattern = '/^(<ul>.*)<li>(.+<\/li><\/ul>)$/'; $replacement = '$1<li id="lastLi">$3'; Perhaps there is an easier approach?? converting to XML to target the LI and then convert back? ie: Single Element <ul> <li>TARGET</li> </ul> Multiple Elements <ul> <li>foo</li> <li>TARGET</li> </ul> Nested Lists before end <ul> <li> foo <ul> <li>bar</li> </ul> <li> <li>TARGET</li> </ul> Nested List at end <ul> <li>foo</li> <li> TARGET <ul> <li>bar</li> </ul> </li> </ul>

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  • Questions about the Backpropogation Algorithm

    - by Colemangrill
    I have a few questions concerning backpropogation. I'm trying to learn the fundamentals behind neural network theory and wanted to start small, building a simple XOR classifier. I've read a lot of articles and skimmed multiple textbooks - but I can't seem to teach this thing the pattern for XOR. Firstly, I am unclear about the learning model for backpropogation. Here is some pseudo-code to represent how I am trying to train the network. [Lets assume my network is setup properly (ie: multiple inputs connect to a hidden layer connect to an output layer and all wired up properly)]. SET guess = getNetworkOutput() // Note this is using a sigmoid activation function. SET error = desiredOutput - guess SET delta = learningConstant * error * sigmoidDerivative(guess) For Each Node in inputNodes For Each Weight in inputNodes[n] inputNodes[n].weight[j] += delta; // At this point, I am assuming the first layer has been trained. // Then I recurse a similar function over the hidden layer and output layer. // The prime difference being that it further divi's up the adjustment delta. I realize this is probably not enough to go off of, and I will gladly expound on any part of my implementation. Using the above algorithm, my neural network does get trained, kind of. But not properly. The output is always XOR 1 1 [smallest number] XOR 0 0 [largest number] XOR 1 0 [medium number] XOR 0 1 [medium number] I can never train the [1,1] [0,0] to be the same value. If you have any suggestions, additional resources, articles, blogs, etc for me to look at I am very interested in learning more about this topic. Thank you for your assistance, I appreciate it greatly!

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  • Regular Expression with Names and Emails

    - by Nina
    I am having a problem with regular expressions at the moment. What I'm trying to do is that for each line through the iteration, it checks for this type of pattern: Lastname, Firstname If it finds the name, then it will take the first letter of the first name, and the first six letters of the lastname and form it as an email. I have the following: $checklast = "[A-z],"; $checkfirst = "[A-z]"; if (ereg($checklast, $parts[1])||ereg($checkfirst, $parts[2])){ $first = preg_replace($checkfirst, $checkfirst{1,1}, $parts[2]); print "<a href='mailto:[email protected];'> $parts[$i] </a>"; } This one obviously broke the code. But I was initially attempting to find only the first letter of the firstname and then after that the first six letters of the lastname followed by the @email.com This didn't work out too well. I'm not sure what to do at this point. Any help is much appreciated.

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  • strcmp() but with 0-9 AFTER A-Z? (C/C++)

    - by Aaron
    For reasons I completely disagree with but "The Powers (of Anti-Usability) That Be" continue to decree despite my objections, I have a sorting routine which does basic strcmp() compares to sort by its name. It works great; it's hard to get that one wrong. However, at the 11th hour, it's been decided that entries which begin with a number should come AFTER entries which begin with a letter, contrary to the ASCII ordering. They cite the EBCDIC standard has numbers following letters so the prior assumption isn't a universal truth, and I have no power to win this argument... but I digress. Therein lies my problem. I've replaced all appropriate references to strcmp with a new function call nonstd_strcmp, and now need to implement the modifications to accomplish the sort change. I've used a FreeBSD source as my base: http://freebsd.active-venture.com/FreeBSD-srctree/newsrc/libkern/strncmp.c.html if (n == 0) return (0); do { if (*s1 != *s2++) return (*(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1)); if (*s1++ == 0) break; } while (--n != 0); return (0); I guess I might need to take some time away to really think about how it should be done, but I'm sure I'm not the only one who's experienced the brain-deadness of just-before-release spec changes.

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  • Exclude subdirectory from rewrite rule in web.config

    - by Clog
    This question comes up often, but I can only find solutions for PHP, Apache, htaccess etc but not for web.config I would like my pages to return in HTTP not HTTPS, except for forms within certain subdirectories. I have created the following web.config file, but how do I exclude a subdirectory called forms. <configuration> <system.webServer> <rewrite> <rules> <rule name="Force all to HTTP" stopProcessing="true"> <match url="(.*)" /> <conditions> <add input="{HTTPS}" pattern="on" ignoreCase="true" /> </conditions> <action type="Redirect" redirectType="Found" url="http://www.mysite.com/{R:1}" /> </rule> </rules> </rewrite> </system.webServer> </configuration> Many thanks all you clever clogs.

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  • How to programmatically create a node in Drupal 8?

    - by chapka
    I'm designing a new module in Drupal 8. It's a long-term project that won't be going public for a few months at least, so I'm using it as a way to figure out what's new. In this module, I want to be able to programmatically create nodes. In Drupal 7, I would do this by creating the object, then calling "node_submit" and "node_save". These functions no longer exist in Drupal 8. Instead, according to the documentation, "Modules and scripts may programmatically submit nodes using the usual form API pattern." I'm at a loss. What does this mean? I've used Form API to create forms in Drupal 7, but I don't get what the docs are saying here. What I'm looking to do is programmatically create at least one and possibly multiple new nodes, based on information not taken directly from a user-presented form. I need to be able to: 1) Specify the content type 2) Specify the URL path 3) Set any other necessary variables that would previously have been handled by the now-obsolete node_object_prepare() 4) Commit the new node object I would prefer to be able to do this in an independent, highly abstracted function not tied to a specific block or form. So what am I missing?

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  • asp.net mvc 2 - return JavaScript with View

    - by Tomaszewski
    Hi, using ASP.NET MVC 2 I have a navigation menu inside my Master Page. In the navigation menu, I am trying add a class to the that the current page relates to (i.e., home page will add class="active" to the Home button). I'm trying to consider scalability and the fact that I don't want to change individual pages if the navigation changes later. The only way I can think of doing this is: Add JavaScript to each individual View that will add the class when the DOM is ready Return JavaScript when return View() occurs on point (2), I am unsure how to do. Thusfar I have been doing the following in my controller: public ActionResult Index() { ViewData["messege"] = JavaScript("<script type='text/javascript' language='javascript'> $(document).ready(function () { console.log('hi hi hi'); }); </script>"); return View(); } but in my view, when I call: <%: ViewData["messege"] %> I get: System.Web.Mvc.JavaScriptResult as the result Would you guys have any ideas on How to solve the navigation menu probelem, other than the solutions I've listed return JavaScript along with your view from the Controller Thanks, in advanced!

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  • What Test Environment Setup do Committers Use in the Ruby Community?

    - by viatropos
    Today I am going to get as far as I can setting up my testing environment and workflow. I'm looking for practical advice on how to setup the test environment from you guys who are very passionate and versed in Ruby Testing. By the end of the day (6am PST?) I would like to be able to: Type one 1-command to run test suites for ANY project I find on Github. Run autotest for ANY Github project so I can fork and make TESTABLE contributions. Build gems from the ground up with Autotest and Shoulda. For one reason or another, I hardly ever run tests for projects I clone from Github. The major reason is because unless they're using RSpec and have a Rake task to run the tests, I don't see the common pattern behind it all. I have built 3 or 4 gems writing tests with RSpec, and while I find the DSL fun, it's less than ideal because it just adds another layer/language of methods I have to learn and remember. So I'm going with Shoulda. But this isn't a question about which testing framework to choose. So the questions are: What is your, the SO reader and Github project committer, test environment setup using autotest so that whenever you git clone a gem, you can run the tests and autotest-develop them if desired? What are the guys who are writing the Paperclip Tests and Authlogic Tests doing? What is their setup? Thanks for the insight. Looking for answers that will make me a more effective tester.

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  • RegEx: difference between "(?:...) and normal parentheses

    - by N0thing
    >>> re.findall(r"(?:do|re|mi)+", "mimi") ['mimi'] >>> re.findall(r"(do|re|mi)+", "mimi") ['mi'] According to my understanding of the definitions, it should produce the same answer. The only difference between (...) and (?:...) should be whether or not we can use back-references later. Am I missing something? (...) Matches whatever regular expression is inside the parentheses, and indicates the start and end of a group; the contents of a group can be retrieved after a match has been performed, and can be matched later in the string with the \number special sequence, described below. To match the literals '(' or ')', use ( or ), or enclose them inside a character class: [(] [)]. (?:...) A non-capturing version of regular parentheses. Matches whatever regular expression is inside the parentheses, but the substring matched by the group cannot be retrieved after performing a match or referenced later in the pattern.

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  • How to maintain form state after Post-Redirect-Get in ASP.net?

    - by Ian Boyd
    Imagine a page with a form input: Search Criteria: crackers                   From: [email protected]           To: [email protected]       Subject: How to maintain form state with PRG? Message: Imagine a page with form input:                         Send After the user clicks Send, the server will instruct to client to Redirect, as part of the Post-Redirect-Get pattern. POST /mail/u/compose HTTP/1.1 303 See Other Location: http://stackoverflow.com/mail/u/compose And the client will issue a GET of the new page. The problem is that some elements of the existing form are lost: Search Criteria:                    It gets worse when there are a few drop-downs, and checkboxes. How can i maintain form state in using Post-Redirect-Get in ASP.net, given that the viewstate is then non-existent. Bonus Reading ASP.NET: How to redirect, prefilling form data?

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  • Focus-dependent text change for TextBoxes in WPF

    - by Simon
    Hey there. I'm writing an application in WPF using the MVVM-pattern and will really often use TextBoxes. I don't want to use labels for the user to know user what the text box is for, i.e. I don't want something like this: <TextBlock> Name: </TextBlock> <TextBox /> Instead, I would like the TextBox to contain its own label. Statically, you would express it like this: <TextBox>Name</TextBox> If the cursor is displayed in the textbox, i.e. the TextBox gains focus, I want the description text to disappear. If the TextBox is left empty and it loses the focus, the description text should be shown again. It's similar to the search textbox of StackOverflow or the one of Firefox. (please tell me if your not sure what I mean). One TextBox's label may change at runtime, dependending on e.g. a ComboBox's selected element or a value in my ViewModel. (It's like in Firefox's search TextBox, if you select google from the search engins' menu, the TextBox's label changes to "Google", if you select "Yahoo" its set to "Yahoo"). Thus I want to be able to bind the label's content. Consider that I may already have a Binding on the Text-Property of the TextBox. How can implement such a behaviour and make it reusable for any of my TextBox's? Code is welcome but not needed; a description of what to do is enough. Thank you in advance.

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  • Entity Framework POCO objects

    - by Dan
    I'm struggling with understanding Entity Framework and POCO objects. Here's what I'm trying to achieve. 1) Separate the DAL from the Business Layer by having my business layer use an interface to my DAL. Maybe use Unity to create my context. 2) Use Entity Framework inside my DAL. I have a Domain model with objects that reside in my business layer. I also have a database full of tables that doesn't really represent my domain model. I setup Entity Framework and generated POCO objects by using the ADO.NET POCO Generator extension. This gave me an object for each table in my database. Now I want to be able to say context.GetAll<User>(); and have it return a list of my User objects. The User object is in my business layer. Is that possible? Does that make sense or am I totally off and should start over? I'm guessing I need to use the repository pattern to achieve this, but I'm not sure. Can anyone help?

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  • Why does this Haskell code produce the "infinite type" error?

    - by Charlie Flowers
    I am new to Haskell and facing a "cannot construct infinite type" error that I cannot make sense of. In fact, beyond that, I have not been able to find a good explanation of what this error even means, so if you could go beyond my basic question and explain the "infinite type" error, I'd really appreciate it. Here's the code: intersperse :: a -> [[a]] -> [a] -- intersperse '*' ["foo","bar","baz","quux"] -- should produce the following: -- "foo*bar*baz*quux" -- intersperse -99 [ [1,2,3],[4,5,6],[7,8,9]] -- should produce the following: -- [1,2,3,-99,4,5,6,-99,7,8,9] intersperse _ [] = [] intersperse _ [x] = x intersperse s (x:y:xs) = x:s:y:intersperse s xs And here's the error trying to load it into the interpreter: Prelude :load ./chapter.3.ending.real.world.haskell.exercises.hs [1 of 1] Compiling Main ( chapter.3.ending.real.world.haskell.exercises.hs, interpreted ) chapter.3.ending.real.world.haskell.exercises.hs:147:0: Occurs check: cannot construct the infinite type: a = [a] When generalising the type(s) for `intersperse' Failed, modules loaded: none. Thanks. EDIT: Thanks to the responses, I have corrected the code and I also have a general guideline for dealing with the "infinite type" error in Haskell: Corrected code intersperse _ [] = [] intersperse _ [x] = x intersperse s (x:xs) = x ++ s:intersperse s xs What the problem was: My type signature states that the second parameter to intersperse is a list of lists. Therefore, when I pattern matched against "s (x:y:xs)", x and y became lists. And yet I was treating x and y as elements, not lists. Guideline for dealing with the "infinite type" error: Most of the time, when you get this error, you have forgotten the types of the various variables you're dealing with, and you have attempted to use a variable as if it were some other type than what it is. Look carefully at what type everything is versus how you're using it, and this will usually uncover the problem.

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  • mysql data read returning 0 rows from class

    - by Neo
    I am implementing a database manager class within my app, mainly because there are 3 databases to connect to one being a local one. However the return function isn't working, I know the query brings back rows but when it is returned by the class it has 0. What am I missing? public MySqlDataReader localfetchrows(string query, List<MySqlParameter> dbparams = null) { using (var conn = connectLocal()) { Console.WriteLine("Connecting local : " + conn.ServerVersion); MySqlCommand sql = conn.CreateCommand(); sql.CommandText = query; if (dbparams != null) { if (dbparams.Count > 0) { sql.Parameters.AddRange(dbparams.ToArray()); } } MySqlDataReader reader = sql.ExecuteReader(); Console.WriteLine("Reading data : " + reader.HasRows + reader.FieldCount); return reader; /* using (MySqlCommand sql = conn.CreateCommand()) { sql.CommandText = query; if (dbparams != null) { if (dbparams.Count > 0) { sql.Parameters.AddRange(dbparams.ToArray()); } } MySqlDataReader reader = sql.ExecuteReader(); Console.WriteLine("Reading data : " + reader.HasRows + reader.FieldCount); sql.Parameters.Clear(); return reader; }*/ } } And the code to get the results query = @"SELECT jobtypeid, title FROM jobtypes WHERE active = 'Y' ORDER BY title ASC"; //parentfrm.jobtypes = db.localfetchrows(query); var rows = db.localfetchrows(query); Console.WriteLine("Reading data : " + rows.HasRows + rows.FieldCount); while (rows.Read()){ } These scripts return the following : Connecting local : 5.5.16 Reading data : True2 Reading data : False0

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  • Testing When Correctness is Poorly Defined?

    - by dsimcha
    I generally try to use unit tests for any code that has easily defined correct behavior given some reasonably small, well-defined set of inputs. This works quite well for catching bugs, and I do it all the time in my personal library of generic functions. However, a lot of the code I write is data mining code that basically looks for significant patterns in large datasets. Correct behavior in this case is often not well defined and depends on a lot of different inputs in ways that are not easy for a human to predict (i.e. the math can't reasonably be done by hand, which is why I'm using a computer to solve the problem in the first place). These inputs can be very complex, to the point where coming up with a reasonable test case is near impossible. Identifying the edge cases that are worth testing is extremely difficult. Sometimes the algorithm isn't even deterministic. Usually, I do the best I can by using asserts for sanity checks and creating a small toy test case with a known pattern and informally seeing if the answer at least "looks reasonable", without it necessarily being objectively correct. Is there any better way to test these kinds of cases?

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  • Modify columns in a data frame in R more cleanly - maybe using with() or apply()?

    - by Mittenchops
    I understand the answer in R to repetitive things is usually "apply()" rather than loop. Is there a better R-design pattern for a nasty bit of code I create frequently? So, pulling tabular data from HTML, I usually need to change the data type, and end up running something like this, to convert the first column to date format (from decimal), and columns 2-4 from character strings with comma thousand separators like "2,400,000" to numeric "2400000." X[,1] <- decYY2YY(as.numeric(X[,1])) X[,2] <- as.numeric(gsub(",", "", X[,2])) X[,3] <- as.numeric(gsub(",", "", X[,3])) X[,4] <- as.numeric(gsub(",", "", X[,4])) I don't like that I have X[,number] repeated on both the left and ride sides here, or that I have basically the same statement repeated for 2-4. Is there a very R-style way of making X[,2] less repetitive but still loop-free? Something that sort of says "apply this to columns 2,3,4---a function that reassigns the current column to a modified version in place?" I don't want to create a whole, repeatable cleaning function, really, just a quick anonymous function that does this with less repetition.

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