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  • JSP to Bean to Java class Validation

    - by littlevahn
    I have a rather simple form in JSP that looks like this: <form action="response.jsp" method="POST"> <label>First Name:</label><input type="text" name="firstName" /><br> <label>Last Name:</label><input type="text" name="lastName" /><br> <label>Email:</label><input type="text" name="email" /><br> <label>Re-enter Email:</label><input type="text" name="emailRe" /><br> <label>Address:</label><input type="text" name="address" /><br> <label>Address 2:</label><input type="text" name="address2" /><br> <label>City:</label><input type="text" name="city" /><br> <label>Country:</label> <select name="country"> <option value="0">--Country--</option> <option value="1">United States</option> <option value="2">Canada</option> <option value="3">Mexico</option> </select><br> <label>Phone:</label><input type="text" name="phone" /><br> <label>Alt Phone:</label><input type="text" name="phoneAlt" /><br> <input type="submit" value="submit" /> </form> But when I try and access the value of the select box in my Java class I get null. Ive tried reading it in as a String and an Array of strings neither though seems to be grabbing the right value. The response.jsp looks like this: <%@ page language="java" %> <%@ page import="java.util.*" %> <%@page contentType="text/html" pageEncoding="UTF-8"%> <%! %> <jsp:useBean id="formHandler" class="validation.RegHandler" scope="request"> <jsp:setProperty name="formHandler" property="*" /> </jsp:useBean> <% if (formHandler.validate()) { %> <jsp:forward page="success.jsp"/> <% } else { %> <jsp:forward page="retryReg.jsp"/> <% } %> I already have Java script validation in place but I wanted to make sure I covered validation and checking for non-JS users. The RegHandler just uses the name field to refer to the value in the form. Any Idea how I could access the select box's value?

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  • App losing db connection

    - by DaveKub
    I'm having a weird issue with an old Delphi app losing it's database connection. Actually, I think it's losing something else that then makes the connection either drop or be unusable. The app is written in Delphi 6 and uses the Direct Oracle Access component (v4.0.7.1) to connect to an Oracle 9i database. The app runs as a service and periodically queries the db using a TOracleQuery object (qryAlarmList). The method that is called to do this looks like this: procedure TdmMain.RefreshAlarmList; begin try qryAlarmList.Execute; except on E: Exception do begin FStatus := ssError; EventLog.LogError(-1, 'TdmMain.RefreshAlarmList', 'Message: ' + E.Message); end; end; end; It had been running fine for years, until a couple of Perl scripts were added to this machine. These scripts run every 15 minutes and look for datafiles to import into the db, and then they do a some calculations and a bunch of reads/writes to/from the db. For some reason, when they are processing large amounts of data, and then the Delphi app tries to query the db, the Delphi app throws an exception at the "qryAlarmList.Execute" line in the above code listing. The exception is always: Access violation at address 00000000. read of address 00000000 HOW can something that the Perl scripts are doing cause this?? There are other Perl scripts on this machine that load data using the same modules and method calls and we didn't have problems. To make it even weirder, there are two other apps that will also suddenly lose their ability to talk to the database at the same time as the Perl stuff is running. Neither of those apps run on this machine, but both are Delphi 6 apps that use the same DOA component to connect to the same database. We have other apps that connect to the same db, written in Java or C# and they don't seem to have any problems. I've tried adding code before the '.Execute' method is called to: check the session's connection (session.CheckConnection(true); always comes back as 'ccOK'). see whether I can access a field of the qryAlarmList object to see if maybe it's become null; can access it fine. check the state of the qryAlarmList; always says it's qsIdle. Does anyone have any suggestions of something to try? This is driving me nuts! Dave

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  • Finding contained bordered regions from Excel imports.

    - by dmaruca
    I am importing massive amounts of data from Excel that have various table layouts. I have good enough table detection routines and merge cell handling, but I am running into a problem when it comes to dealing with borders. Namely performance. The bordered regions in some of these files have meaning. Data Setup: I am importing directly from Office Open XML using VB6 and MSXML. The data is parsed from the XML into a dictionary of cell data. This wonks wonderfully and is just as fast as using docmd.transferspreadsheet in Access, but returns much better results. Each cell contains a pointer to a style element which contains a pointer to a border element that defines the visibility and weight of each border (this is how the data is structured inside OpenXML, also). Challenge: What I'm trying to do is find every region that is enclosed inside borders, and create a list of cells that are inside that region. What I have done: I initially created a BFS(breadth first search) fill routine to find these areas. This works wonderfully and fast for "normal" sized spreadsheets, but gets way too slow for imports into the thousands of rows. One problem is that a border in Excel could be stored in the cell you are checking or the opposing border in the adjacent cell. That's ok, I can consolidate that data on import to reduce the number of checks needed. One thing I thought about doing is to create a separate graph that outlines the cells using the borders as my edges and using a graph algorithm to find regions that way, but I'm having trouble figuring out how to implement the algorithm. I've used Dijkstra in the past and thought I could do similar with this. So I can span out using no endpoint to search the entire graph, and if I encounter a closed node I know that I just found an enclosed region, but how can I know if the route I've found is the optimal one? I guess I could flag that to run a separate check for the found closed node to the previous node ignoring that one edge. This could work, but wouldn't be much better performance wise on dense graphs. Can anyone else suggest a better method? Thanks for taking the time to read this.

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  • Sessions not persisting between requests

    - by klonq
    My session objects are only stored within the request scope on google app engine and I can't figure out how to persist objects between requests. The docs are next to useless on this matter and I can't find anyone who's experienced a similar problem. Please help. When I store session objects in the servlet and forward the request to a JSP using: getServletContext().getRequestDispatcher("/example.jsp").forward(request,response); Everything works like it should. But when I store objects to the session and redirect the request using: response.sendRedirect("/example/url"); The session objects are lost to the ether. In fact when I dump session key/value pairs on new requests there is absolutely nothing, session objects only appear within the request scope of servlets which create session objects. It appears to me that the objects are not being written to Memcache or Datastore. In terms of configuring sessions for my application I have set <sessions-enabled>true</sessions-enabled> In appengine-web.xml. Is there anything else I am missing? The single paragraph of documentation on sessions also notes that only objects which implement Serializable can be stored in the session between requests. I have included an example of the code which is not working below. The obvious solution is to not use redirects, and this might be ok for the example given below but some application data does need to be stored in the session between requests so I need to find a solution to this problem. EXAMPLE: The class FlashMessage gives feedback to the user from server-side operations. if (email.send()) { FlashMessage flash = new FlashMessage(FlashMessage.SUCCESS, "Your message has been sent."); session.setAttribute(FlashMessage.SESSION_KEY, flash); // The flash message will not be available in the session object in the next request response.sendRedirect(URL.HOME); } else { FlashMessage flash = new FlashMessage(FlashMessage.ERROR, FlashMessage.INVALID_FORM_DATA); session.setAttribute(FlashMessage.SESSION_KEY, flash); // The flash message is displayed without problem getServletContext().getRequestDispatcher(Templates.CONTACT_FORM).forward(request,response); } FlashMessage.java import java.io.Serializable; public class FlashMessage implements Serializable { private static final long serialVersionUID = 8109520737272565760L; // I have tried using different, default and no serialVersionUID public static final String SESSION_KEY = "flashMessage"; public static final String ERROR = "error"; public static final String SUCCESS = "success"; public static final String INVALID_FORM_DATA = "Your request failed to validate."; private String message; private String type; public FlashMessage (String type, String message) { this.type = type; this.message = message; } public String display(){ return "<div id='flash' class='" + type + "'>" + message + "</div>"; } }

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  • Reading three words and sorting them in lexicographic order

    - by Derrick
    I am trying to create a program that asks the User to type three words and sort them in lexicographic order. EXAMPLE; Enter three words separated by spaces: Pear Orange Apple Apple Orange Pear The program is working fine (if I attempt the above example) except for one type of combination example that I will show below. EXAMPLE; Enter three words separated by spaces: Orange Apple Pear Apple Pear Pear The program is skipping the first word (Orange) if it is supposed to appear in the middle of the three words. I believe that this line of code is affecting the program because it says that "this assigned value is never used" but I'm not sure how to fix it since I'm still an entry Java learner. middle = firstWord; Because of that line being unused, it's why Pear appeared twice. import java.util.*; public static void main(String[] args) { Scanner wordInput = new Scanner(System.in); String firstWord; String secondWord; String thirdWord; System.out.println("Enter three words separated by spaces: "); firstWord = wordInput.next(); secondWord = wordInput.next(); thirdWord = wordInput.next(); String top = firstWord; String bottom = firstWord; if( top.compareTo(secondWord) > 0) { top = secondWord; } if( top.compareTo(thirdWord) > 0) { top = thirdWord; } if( bottom.compareTo(secondWord) < 0) { bottom = secondWord; } if( bottom.compareTo(thirdWord) < 0) { bottom = thirdWord; } String middle; if( !firstWord.equals(bottom) && !firstWord.equals(top) ) { middle = firstWord; } if( !secondWord.equals(bottom) && !secondWord.equals(top) ) { middle = secondWord; } else { middle = thirdWord; } System.out.println( top ); System.out.println( middle ); System.out.println( bottom ); } } Does anyone what I am missing or doing wrong? :( Please and thank you for any help!

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  • Parsing CSV File to MySQL DB in PHP

    - by Austin
    I have a some 350-lined CSV File with all sorts of vendors that fall into Clothes, Tools, Entertainment, etc.. categories. Using the following code I have been able to print out my CSV File. <?php $fp = fopen('promo_catalog_expanded.csv', 'r'); echo '<tr><td>'; echo implode('</td><td>', fgetcsv($fp, 4096, ',')); echo '</td></tr>'; while(!feof($fp)) { list($cat, $var, $name, $var2, $web, $var3, $phone,$var4, $kw,$var5, $desc) = fgetcsv($fp, 4096); echo '<tr><td>'; echo $cat. '</td><td>' . $name . '</td><td><a href="http://www.' . $web .'" target="_blank">' .$web.'</a></td><td>'.$phone.'</td><td>'.$kw.'</td><td>'.$desc.'</td>' ; echo '</td></tr>'; } fclose($file_handle); show_source(__FILE__); ?> First thing you will probably notice is the extraneous vars within the list(). this is because of how the excel spreadsheet/csv file: Category,,Company Name,,Website,,Phone,,Keywords,,Description ,,,,,,,,,, Clothes,,4imprint,,4imprint.com,,877-466-7746,,"polos, jackets, coats, workwear, sweatshirts, hoodies, long sleeve, pullovers, t-shirts, tees, tshirts,",,An embroidery and apparel company based in Wisconsin. ,,Apollo Embroidery,,apolloemb.com,,1-800-982-2146,,"hats, caps, headwear, bags, totes, backpacks, blankets, embroidery",,An embroidery sales company based in California. One thing to note is that the last line starts with two commas as it is also listed within "Clothes" category. My concern is that I am going about the CSV output wrong. Should I be using a foreach loop instead of this list way? Should I first get rid of any unnecessary blank columns? Please advise any flaws you may find, improvements I can use so I can be ready to import this data to a MySQL DB.

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  • Best way to version control a WCF application with Git?

    - by Sam
    Suppose I have the following projects. The format is [ProjectName] : [ProjectDependency1, ProjectDependency2, etc.] // Service CoolLibrary WcfApp.Core WcfApp.Contracts WcfApp.Services : CoolLibrary, WcfApp.Core, WcfApp.Contracts // Clients CustomerX.App : WcfApp.Contracts CustomerY.App : WcfApp.Contracts CustomerZ.App : WcfApp.Contracts (On a side note, WcfApp.Contracts should not depend on WcfApp.Core, right? Else CustomerX.App would also depend on and thus be exposed to the service domain model?) (CoolLibrary is shared with other applications, so I can't just put it inside of WcfApp.Services.) All of this code is in-house. I was thinking of having 6 repositories for this. The format is [repository folder name] : [Projects included in repository.] 1. CoolLibrary.git : CoolLibrary 2. WcfApp.Contracts.git : WcfApp.Contracts 3. WcfApp.git : WcfApp.Core, WcfApp.Services 4. CustomerX.App.git : CustomerX.App 5. CustomerY.App.git : CustomerY.App 6. CustomerZ.App.git : CustomerZ.App How should I manage my project dependencies? I see three options: I could use binaries which I have to manually copy to each dependent repository. This would be easiest at the start, but my repositories would be a little bloated, and it'd become more tedious as I add more client apps for customers. I could import dependent code as submodules. This is what I will probably end up doing, although I keep reading on the web that submodules are a hassle. I also read that I can use something called the subtree merge strategy, but I am not sure how it is different from just cloning the repo into a subdirectory and adding the subdirectory to .gitignore. Is the difference that the subtree is recorded in the master repository, so (for example) cloning it from a different location will also pull the subtree? I know I asked a lot of questions in this post, but the most important two questions I have are: 1. Am I using the right number and layout of repositories? Should I use less or more? 2. Which of the three dependency management strategies would you recommend? Is there another strategy I haven't considered?

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  • Cross-site request forgery protections: Where do I put all these lines?

    - by brilliant
    Hello, I was looking for a python code that would be able to log in from "Google App Engine" to some of my accounts on some websites (like yahoo or eBay) and was given this code: import urllib, urllib2, cookielib url = "https://login.yahoo.com/config/login?" form_data = {'login' : 'my-login-here', 'passwd' : 'my-password-here'} jar = cookielib.CookieJar() opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(jar)) form_data = urllib.urlencode(form_data) # data returned from this pages contains redirection resp = opener.open(url, form_data) # yahoo redirects to http://my.yahoo.com, so lets go there instead resp = opener.open('http://mail.yahoo.com') print resp.read() Unfortunately, this code didn't work, so I asked another question here and one supporter among other things said this: "You send MD5 hash and not plain password. Also you'd have to play along with all kinds of CSRF protections etc. that they're implementing. Look: <input type="hidden" name=".tries" value="1"> <input type="hidden" name=".src" value="ym"> <input type="hidden" name=".md5" value=""> <input type="hidden" name=".hash" value=""> <input type="hidden" name=".js" value=""> <input type="hidden" name=".last" value=""> <input type="hidden" name="promo" value=""> <input type="hidden" name=".intl" value="us"> <input type="hidden" name=".bypass" value=""> <input type="hidden" name=".partner" value=""> <input type="hidden" name=".u" value="bd5tdpd5rf2pg"> <input type="hidden" name=".v" value="0"> <input type="hidden" name=".challenge" value="5qUiIPGVFzRZ2BHhvtdGXoehfiOj"> <input type="hidden" name=".yplus" value=""> <input type="hidden" name=".emailCode" value=""> <input type="hidden" name="pkg" value=""> <input type="hidden" name="stepid" value=""> <input type="hidden" name=".ev" value=""> <input type="hidden" name="hasMsgr" value="0"> <input type="hidden" name=".chkP" value="Y"> <input type="hidden" name=".done" value="http://mail.yahoo.com"> <input type="hidden" name=".pd" value="ym_ver=0&c=&ivt=&sg="> I am not quite sure where he got all these lines from and where in my code I am supposed to add them. Do You have any idea? I know I was supposed to ask him this question first, and I did, but he never returned, so I decided to ask a separate question here.

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  • UIScrollView does not scroll

    - by Preston Cheung
    I got a problem about UIScrollView. I am making a custom view which inherits UIView. The view has a UIScrollView on which there are lots of buttons which should scroll left and right. The UIScrollView and buttons can show normally. But I cannot scroll the buttons. Could someone give me some suggestions? Thanks a lot! MZMPhotoCalenderSwitcher.h #import <UIKit/UIKit.h> @interface MZMPhotoCalenderSwitcher : UIView <UIScrollViewDelegate> @property (strong, nonatomic) UIScrollView *topSwitcher; @end MZMPhotoCalenderSwitcher.m - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. self.topSwitcher = [[UIScrollView alloc] initWithFrame:CGRectMake(0, LABEL_HEIGHT + VIEW_Y, self.view.bounds.size.width, TOP_SWITCHER_HEIGHT)]; self.topSwitcher.backgroundColor = [UIColor greenColor]; self.topSwitcher.pagingEnabled = YES; self.topSwitcher.showsHorizontalScrollIndicator = NO; self.topSwitcher.showsVerticalScrollIndicator = NO; [self add:3 ButtonsOnView:self.topSwitcher withButtonWidth:44.8f andHeight:20.0f]; } - (void)add:(int)num ButtonsOnView:(UIScrollView *)view withButtonWidth:(CGFloat)width andHeight:(CGFloat)height { CGFloat totalTopSwitcherWidth = num * width; [view setContentSize:CGSizeMake(totalTopSwitcherWidth, view.bounds.size.height)]; CGFloat xOffset = 0.0f; for (int i=1; i<=num; i++) { UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect]; [button setFrame:CGRectMake(xOffset, 0, width, height)]; xOffset += width; [button setTitle:[NSString stringWithFormat:@"%d", i] forState:UIControlStateNormal]; button.titleLabel.font = [UIFont systemFontOfSize:10]; [button setTitleColor:[UIColor blueColor] forState:UIControlStateNormal]; [button setTitleColor:[UIColor blackColor] forState:UIControlStateSelected]; [button setTag:i]; [button addTarget:self action:@selector(buttonEvent) forControlEvents:UIControlEventTouchUpInside]; if (i % 2 == 0) [button setBackgroundColor:[UIColor yellowColor]]; else [button setBackgroundColor:[UIColor redColor]]; [view addSubview:button]; } }

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  • Programatically created UITableViewCell subclass only working on highlight

    - by squarefrog
    I've created a subclass of UITableViewCell but I'm struggling to get it to work properly. If I use UITableViewStyleDefault then the class only works when highlighted. If I use UITableViewStyleValue1 then it mostly works but I'm unable to change label fonts much. I tried researching but it seems everyone is doing this via a .xib file, but not programatically. Implementation file #import "ASCustomCellWithCount.h" @implementation ASCustomCellWithCount @synthesize primaryLabel,secondaryLabel,contentCountImage,contentCount; - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier { self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]; if (self) { // Initialization code contentCountImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed: @"tableCount.png"] ]; primaryLabel = [[UILabel alloc] init]; primaryLabel.textAlignment = UITextAlignmentLeft; primaryLabel.textColor = [UIColor blackColor]; primaryLabel.font = [UIFont systemFontOfSize: 20]; primaryLabel.backgroundColor = [UIColor clearColor]; secondaryLabel = [[UILabel alloc] init]; secondaryLabel.textAlignment = UITextAlignmentLeft; secondaryLabel.textColor = [UIColor blackColor]; secondaryLabel.font = [UIFont systemFontOfSize: 8]; secondaryLabel.backgroundColor = [UIColor clearColor]; contentCount = [[UILabel alloc] init]; contentCount.textAlignment = UITextAlignmentCenter; contentCount.font = [UIFont boldSystemFontOfSize: 15]; contentCount.textColor = [UIColor whiteColor]; contentCount.shadowColor = [UIColor blackColor]; contentCount.shadowOffset = CGSizeMake(1, 1); contentCount.backgroundColor = [UIColor clearColor]; [self.contentView addSubview: contentCountImage]; [self.contentView addSubview: primaryLabel]; [self.contentView addSubview: secondaryLabel]; [self.contentView addSubview: contentCount]; } return self; } - (void)layoutSubviews { [super layoutSubviews]; CGRect contentRect = self.contentView.bounds; // CGFloat boundsX = contentRect.origin.x; primaryLabel.frame = CGRectMake(0 ,0, 200, 25); secondaryLabel.frame = CGRectMake(0, 30, 100, 15); contentCount.frame = CGRectMake(contentRect.size.width - 48, contentRect.size.height / 2 - 13, 36, 24); contentCountImage.frame = CGRectMake(contentRect.size.width - 48, contentRect.size.height / 2 - 12, 36, 24); } - (void)setSelected:(BOOL)selected animated:(BOOL)animated { [super setSelected:selected animated:animated]; // Configure the view for the selected state } - (void)dealloc { [primaryLabel release]; [secondaryLabel release]; [contentCountImage release]; [contentCount release]; } @end And then to create the cell I use - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; ASCustomCellWithCount *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[ASCustomCellWithCount alloc] initWithStyle: UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } cell.textLabel.text = [NSString stringWithFormat:@"%@", [tempArray objectAtIndex: indexPath.row]]; cell.contentCount.text = @"49"; return cell; }

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  • Assign value to HTML textbox from JSP

    - by prakash_d22
    Hello I am creating a web page to add some information about given product.I need to enter id,name,description and image as information.I need the id to be auto generated.I am using jsp and database as access.I am fetching the count(*)+1 value from database and assigning to my html text box but its showing as null.can i get some help? Code: <body> <%@page import="java.sql.*"%> <%! String no; %> <% try{ Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); Connection con = DriverManager.getConnection("jdbc:odbc:pd"); ResultSet rs = null; Statement st = con.createStatement(); String sql = ("select count(*)+1 from products"); st.executeUpdate(sql); while (rs.next()) { no=rs.getString("count(*)+1"); } rs.close(); st.close(); con.close(); } catch(Exception e){} %> <Form name='Form1' action="productcode.jsp" method="post"> <table width="1024" border="0"> <tr> <td width="10">&nbsp;</td> <td width="126">Add Product: </td> <td width="277">&nbsp;</td> <td width="583">&nbsp;</td> </tr> <tr> <td>&nbsp;</td> <td>Product Id:</td> <td><label> <input type="text" name="id" value="<%= no%>"/> </label></td> <td>&nbsp;</td> .... and so on

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  • populate CoreData data model from JSON files prior to app start

    - by johannes_d
    I am creating an iPad App that displays data I got from an API in JSON format. My Core Data model has several entities(Countries, Events, Talks, ...). For each entity I have one .json file that contains all instances of the entity and its attributes as well as its relationships. I would like to populate my Core Data data model with these entities before the start of the App (otherwise it takes about 15 minutes for the iPad to create all the instances of the entities from the several JSON files using factory methods). I am currently importing the data into CoreData like this: -(void)fetchDataIntoDocument:(UIManagedDocument *)document { dispatch_queue_t dataQ = dispatch_queue_create("Data import", NULL); dispatch_async(dataQ, ^{ //Fetching data from application bundle NSURL *tedxgroupsurl = [[NSBundle mainBundle] URLForResource:@"contries" withExtension:@"json"]; NSURL *tedxeventsurl = [[NSBundle mainBundle] URLForResource:@"events" withExtension:@"json"]; //converting the JSON files to NSDictionaries NSError *error = nil; NSDictionary *countries = [NSJSONSerialization JSONObjectWithData:[NSData dataWithContentsOfURL:countriesurl] options:kNilOptions error:&error]; countries = [countries objectForKey:@"countries"]; NSDictionary *events = [NSJSONSerialization JSONObjectWithData:[NSData dataWithContentsOfURL:eventsurl] options:kNilOptions error:&error]; events = [events objectForKey:@"events"]; //creating entities using factory methods in NSManagedObject Subclasses (Country / Event) [document.managedObjectContext performBlock:^{ NSLog(@"creating countries"); for (NSDictionary *country in countries) { [Country countryWithCountryInfo:country inManagedObjectContext:document.managedObjectContext]; //creating Country entities } NSLog(@"creating events"); for (NSDictionary *event in events) { [Event eventWithEventInfo:event inManagedObjectContext:document.managedObjectContext]; // creating Event entities } NSLog(@"done creating, saving document"); [document saveToURL:document.fileURL forSaveOperation:UIDocumentSaveForOverwriting completionHandler:NULL]; }]; }); dispatch_release(dataQ); } This combines the different JSON files into one UIManagedDocument which i can then perform fetchRequests on to populate tableViews, mapView, etc. I'm looking for a way to create this document outside my application & add it to the mainBundle. Then I could copy it once to the apps DocumentsDirectory and be able I use it (instead of creating the Document within the app from the original JSON files). Any help is appreciated!

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  • go programming POST FormValue can't be printed

    - by poor_programmer
    Before I being a bit of background, I am very new to go programming language. I am running go on Win 7, latest go package installer for windows. I'm not good at coding but I do like some challenge of learning a new language. I wanted to start learn Erlang but found go very interesting based on the GO I/O videos in youtube. I'm having problem with capturing POST form values in GO. I spend three hours yesterday to get go to print a POST form value in the browser and failed miserably. I don't know what I'm doing wrong, can anyone point me to the right direction? I can easily do this in another language like C#, PHP, VB, ASP, Rails etc. I have search the entire interweb and haven't found a working sample. Below is my sample code. Here is Index.html page {{ define "title" }}Homepage{{ end }} {{ define "content" }} <h1>My Homepage</h1> <p>Hello, and welcome to my homepage!</p> <form method="POST" action="/"> <p> Enter your name : <input type="text" name="username"> </P> <p> <button>Go</button> </form> <br /><br /> {{ end }} Here is the base page <!DOCTYPE html> <html lang="en"> <head> <title>{{ template "title" . }}</title> </head> <body> <section id="contents"> {{ template "content" . }} </section> <footer id="footer"> My homepage 2012 copy </footer> </body> </html> now some go code package main import ( "fmt" "http" "strings" "html/template" ) var index = template.Must(template.ParseFiles( "templates/_base.html", "templates/index.html", )) func GeneralHandler(w http.ResponseWriter, r *http.Request) { index.Execute(w, nil) if r.Method == "POST" { a := r.FormValue("username") fmt.Fprintf(w, "hi %s!",a); //<-- this variable does not rendered in the browser!!! } } func helloHandler(w http.ResponseWriter, r *http.Request) { remPartOfURL := r.URL.Path[len("/hello/"):] fmt.Fprintf(w, "Hello %s!", remPartOfURL) } func main() { http.HandleFunc("/", GeneralHandler) http.HandleFunc("/hello/", helloHandler) http.ListenAndServe("localhost:81", nil) } Thanks! PS: Very tedious to add four space before every line of code in stackoverflow especially when you are copy pasting. Didn't find it very user friendly or is there an easier way?

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  • What am I encrypting wrong here?

    - by Katie Krueger
    So I have a wordplay project to do and I have to encrypt some characters. I am at the point where I am stuck, and when I run it and type 1 for encrypt it doesn't shift that many letters. It just prints the work over again. I am wondering what I could do to fix it where if I say "hello" it will print 1 character over and say "ifmmp" Thank you! import java.util.Scanner; public class WordPlayTester{ public static void main(String [] args){ String word, reverse=""; String original; int key= 0; String Menu= "1-Encrypt \n2-Decrypt \n3-Is Palindrome \n0-Quit \n-Select an option-"; Scanner in = new Scanner(System.in); System.out.println("-Type any word-"); word = in.nextLine(); System.out.println(Menu); int choice=in.nextInt(); if(choice==1) { System.out.println("Insert a Key number"); int select= in.nextInt(); for (int i=0; i < word.length(); i++) { char c = word.charAt(i); if (c >= 'A' && c <= 'Z') { c = (char)(c - 64); int n = c+1; n = n % 26; if (n < 0) { n = n + 26; } c = (char)(n + 65); } System.out.println(c); } } else if(choice==3) { int length = word.length(); for ( int i = length - 1 ; i >= 0 ; i-- ) reverse = reverse + word.charAt(i); if (word.equals(reverse)) System.out.println("Your word is a palindrome."); else System.out.println("Your word is not a palindrome."); } else if(choice==0) { System.exit(0); } else { System.out.println(Menu); } } }

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  • CGAffineTransformMakeRotation goes the other way after 180 degrees (-3.14)

    - by TheKillerDev
    So, i am trying to do a very simple disc rotation (2d), according to the user touch on it, just like a DJ or something. It is working, but there is a problem, after certain amount of rotation, it starts going backwards, this amount is after 180 degrees or as i saw in while logging the angle, -3.14 (pi). I was wondering, how can i achieve a infinite loop, i mean, the user can keep rotating and rotating to any side, just sliding his finger? Also a second question is, is there any way to speed up the rotation? Here is my code right now: #import <UIKit/UIKit.h> @interface Draggable : UIImageView { CGPoint firstLoc; UILabel * fred; double angle; } @property (assign) CGPoint firstLoc; @property (retain) UILabel * fred; @end @implementation Draggable @synthesize fred, firstLoc; - (id)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; angle = 0; if (self) { // Initialization code } return self; } -(void)handleObject:(NSSet *)touches withEvent:(UIEvent *)event isLast:(BOOL)lst { UITouch *touch =[[[event allTouches] allObjects] lastObject]; CGPoint curLoc = [touch locationInView:self]; float fromAngle = atan2( firstLoc.y-self.center.y, firstLoc.x-self.center.x ); float toAngle = atan2( curLoc.y-(self.center.y+10), curLoc.x-(self.center.x+10)); float newAngle = angle + (toAngle - fromAngle); NSLog(@"%f",newAngle); CGAffineTransform cgaRotate = CGAffineTransformMakeRotation(newAngle); self.transform = cgaRotate; if (lst) angle = newAngle; } -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch =[[[event allTouches] allObjects] lastObject]; firstLoc = [touch locationInView:self]; }; -(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { [self handleObject:touches withEvent:event isLast:NO]; }; -(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { [self handleObject:touches withEvent:event isLast:YES]; } @end And in the ViewController: UIImage *tmpImage = [UIImage imageNamed:@"theDisc.png"]; CGRect cellRectangle; cellRectangle = CGRectMake(-1,self.view.frame.size.height,tmpImage.size.width ,tmpImage.size.height ); dragger = [[Draggable alloc] initWithFrame:cellRectangle]; [dragger setImage:tmpImage]; [dragger setUserInteractionEnabled:YES]; dragger.layer.anchorPoint = CGPointMake(.5,.5); [self.view addSubview:dragger]; I am open to new/cleaner/more correct ways of doing this too. Thanks in advance.

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  • javascript-aware html parser for Python ~

    - by znetor
    <html> <head> <script type="text/javascript"> document.write('<a href="http://www.google.com">f*** js</a>'); document.write("f*** js!"); </script> </head> <body> <script type="text/javascript"> document.write('<a href="http://www.google.com">f*** js</a>'); document.write("f*** js!"); </script> <div><a href="http://www.google.com">f*** js</a></div> </body> </html> I want use xpath to catch all lable object in the html page above... In [1]: import lxml.html as H In [2]: f = open("test.html","r") In [3]: c = f.read() In [4]: doc = H.document_fromstring(c) In [5]: doc.xpath('//a') Out[5]: [<Element a at a01d17c>] In [6]: a = doc.xpath('//a')[0] In [7]: a.getparent() Out[7]: <Element div at a01d41c> I only get one don't generate by js~ but firefox xpath checker can find all lable!? http://i.imgur.com/0hSug.png how to do that??? thx~! <html> <head> </head> <body> <script language="javascript"> function over(){ a.innerHTML="mouse me" } function out(){ a.innerHTML="<a href='http://www.google.com'>google</a>" } </script> <body><li id="a"onmouseover="over()" onmouseout="out()">mouse me</li> </body> </html>

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  • A question about making a C# class persistent during a file load

    - by Adam
    Apologies for the indescriptive title, however it's the best I could think of for the moment. Basically, I've written a singleton class that loads files into a database. These files are typically large, and take hours to process. What I am looking for is to make a method where I can have this class running, and be able to call methods from within it, even if it's calling class is shut down. The singleton class is simple. It starts a thread that loads the file into the database, while having methods to report on the current status. In a nutshell it's al little like this: public sealed class BulkFileLoader { static BulkFileLoader instance = null; int currentCount = 0; BulkFileLoader() public static BulkFileLoader Instance { // Instanciate the instance class if necessary, and return it } public void Go() { // kick of 'ProcessFile' thread } public void GetCurrentCount() { return currentCount; } private void ProcessFile() { while (more rows in the import file) { // insert the row into the database currentCount++; } } } The idea is that you can get an instance of BulkFileLoader to execute, which will process a file to load, while at any time you can get realtime updates on the number of rows its done so far using the GetCurrentCount() method. This works fine, except the calling class needs to stay open the whole time for the processing to continue. As soon as I stop the calling class, the BulkFileLoader instance is removed, and it stops processing the file. What I am after is a solution where it will continue to run independently, regardless of what happens to the calling class. I then tried another approach. I created a simple console application that kicks off the BulkFileLoader, and then wrapped it around as a process. This fixes one problem, since now when I kick off the process, the file will continue to load even if I close the class that called the process. However, now the problem I have is that cannot get updates on the current count, since if I try and get the instance of BulkFileLoader (which, as mentioned before is a singleton), it creates a new instance, rather than returning the instance that is currently in the executing process. It would appear that singletons don't extend into the scope of other processes running on the machine. In the end, I want to be able to kick off the BulkFileLoader, and at any time be able to find out how many rows it's processed. However, that is even if I close the application I used to start it. Can anyone see a solution to my problem?

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  • How can i maintain last cookie value in flex with jsp?

    - by praveen
    Hi All, my login form in flex when I login I have created a cookie in jsp like this name setValueCookie.jsp <%@ page language="java" import="java.util.* , javax.net.*" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <% String username = request.getParameter("value"); System.out.println("Email got in cookieSet = " + username); if(username==null) username=""; Date now = new Date(); String timestamp = now.toString(); Cookie cookie = new Cookie("username",username); cookie.setMaxAge(365 * 24 * 60 * 60); response.addCookie(cookie); %> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>DashBoard-Cookie</title> </head> <body> </body> </html> now using Http service request parameter i am passing username 'Value' to this jsp. and i am reading cookie value from getValueCookie.jsp like this <% String cookieName = "username"; Cookie cookies [] = request.getCookies (); Cookie myCookie = null; String result; if (cookies != null) { for (int i = 0; i < cookies.length; i++) { if (cookies [i].getName().equals (cookieName)) { myCookie = cookies[i]; break; } } } %> <data> <status><%=myCookie.getValue().toString()%></status> </data> through the httpservice value i am getting but if i open a new window or any new tab cookie value is not getting how can i solve this? Thanks in advance.

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  • SQLite/iPhone read copyright symbol

    - by Marco A
    Hi All, I am having problems reading the copyright symbol from a sqlite db that I have for my App that I am developing. I import the information manually, ie, from an excel sheet. I have tried two ways of doing it and failed with both: 1) Tried replacing the copyright symbol with "\u00ae" (unicode combination) within excel and then importing the modified file. - Result: I get the combination of \u00ae as a part of the string, it doesnt detect the unicode combination. 2) Tried leaving as it is. Importing the excel with the copyright symbol. - Result: I get a symbol that is different from the copyright, its something like an AE put together.looks like this: Æ Heres my code how I read from DB: -(void) readCategoriesFromDatabase:(NSString *) rest_input { // Init the products Array categories = [[NSMutableArray alloc] init]; // Open the database from the users filessytem rest_input = [rest_input stringByAppendingString:@"'"]; NSString *newString; newString = [@"select distinct category from food where restaurant='" stringByAppendingString:rest_input]; const char *cat_sqlStatement = [newString UTF8String]; sqlite3_stmt *cat_compiledStatement; if(sqlite3_prepare_v2(database, cat_sqlStatement, -1, &cat_compiledStatement, NULL) == SQLITE_OK) { // Loop through the results and add them to the feeds array while(sqlite3_step(cat_compiledStatement) == SQLITE_ROW) { NSString *catName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(cat_compiledStatement,0)]; // Create a new product object with the data from the database Product *category = [[Product alloc] initWithName:catName]; // Add the product object to the respective Array [categories addObject:category]; [category release]; } sqlite3_finalize(cat_compiledStatement); } NSLog(@"Finished Accessing Database to gather Categories...."); } I open the DB with this function: -(void) checkAndCreateDatabase{ NSLog(@"Checking/Creating Database...."); NSFileManager *fileManager = [NSFileManager defaultManager]; success = [fileManager fileExistsAtPath:databasePath]; [fileManager removeFileAtPath:databasePath handler:nil]; NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName]; [fileManager copyItemAtPath:databasePathFromApp toPath:databasePath error:nil]; [fileManager release]; if (sqlite3_open([databasePath UTF8String], &database) != SQLITE_OK) { sqlite3_close(database); database = nil; } NSLog(@"Finished Checking/Creating Database...."); } Thanks to anything that can help me out.

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  • Basic drawing with Quartz 2D on iPhone

    - by wwrob
    My goal is to make a program that will draw points whenever the screen is touched. This is what I have so far: The header file: #import <UIKit/UIKit.h> @interface ElSimView : UIView { CGPoint firstTouch; CGPoint lastTouch; UIColor *pointColor; CGRect *points; int npoints; } @property CGPoint firstTouch; @property CGPoint lastTouch; @property (nonatomic, retain) UIColor *pointColor; @property CGRect *points; @property int npoints; @end The implementation file: //@synths etc. - (id)initWithFrame:(CGRect)frame { return self; } - (id)initWithCoder:(NSCoder *)coder { if(self = [super initWithCoder:coder]) { self.npoints = 0; } return self; } - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; firstTouch = [touch locationInView:self]; lastTouch = [touch locationInView:self]; } - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; lastTouch = [touch locationInView:self]; points = (CGRect *)malloc(sizeof(CGRect) * ++npoints); points[npoints-1] = CGRectMake(lastTouch.x-15, lastTouch.y-15,30,30); [self setNeedsDisplay]; } - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; lastTouch = [touch locationInView:self]; [self setNeedsDisplay]; } - (void)drawRect:(CGRect)rect { CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSetLineWidth(context, 2.0); CGContextSetStrokeColorWithColor(context, [UIColor blackColor].CGColor); CGContextSetFillColorWithColor(context, pointColor.CGColor); for(int i=0; i<npoints; i++) CGContextAddEllipseInRect(context, points[i]); CGContextDrawPath(context, kCGPathFillStroke); } - (void)dealloc { free(points); [super dealloc]; } @end When I load this and click some points, it draws the first points normally, then then next points are drawn along with random ellipses (not even circles). Also I have another question: When is exactly drawRect executed?

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  • Flex bug?? Get messed up stacked ColumnChart with type="100%"

    - by Nir
    I am trying to do a stacked Column chart with type="100%" and a mixture of positive and negative values. When all the values are positive, is functions well, but when negative numbers come to the game, it looks totally messed up. When I also look at Adobe documentation (look here), I see the following code for stacked column chart involving negative numbers: <?xml version="1.0"?> <!-- charts/StackedNegative.mxml --> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:Script><![CDATA[ import mx.collections.ArrayCollection; [Bindable] public var expenses:ArrayCollection = new ArrayCollection([ {Month:"Jan", Profit:-2000, Expenses:-1500}, {Month:"Feb", Profit:1000, Expenses:-200}, {Month:"Mar", Profit:1500, Expenses:-500} ]); ]]></mx:Script> <mx:Panel title="Column Chart"> <mx:ColumnChart id="myChart" dataProvider="{expenses}" showDataTips="true"> <mx:horizontalAxis> <mx:CategoryAxis dataProvider="{expenses}" categoryField="Month" /> </mx:horizontalAxis> <mx:series> <mx:ColumnSet type="stacked" allowNegativeForStacked="true"> <mx:series> <mx:ColumnSeries xField="Month" yField="Profit" displayName="Profit" /> <mx:ColumnSeries xField="Month" yField="Expenses" displayName="Expenses" /> </mx:series> </mx:ColumnSet> </mx:series> </mx:ColumnChart> <mx:Legend dataProvider="{myChart}"/> </mx:Panel> </mx:Application> It works fine. But try to change: <mx:ColumnSet type="stacked" allowNegativeForStacked="true"> to: <mx:ColumnSet type="100%" allowNegativeForStacked="true"> and you'll see that it doesn't on January data, where both values are negative, the chart shows as if they are positive, and on the other two where one value is positive and the other is negative, it shows only the positive part as 100%... Isn't it a Flex Bug? I have my own case with such data and it behaves wrong the same way. I'd expect that if it has 800 stacked on -200, it will show 80% up and 20% down, totalling 100%. BTW: Using Flex 4, though these are all mx components. Thanks a lot and regards from Berlin, Germany, Nir.

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  • I need to modify a program to use arrays and a method call. Should I modify the running file, the data collection file, or both?

    - by g3n3rallyl0st
    I have to have multiple classes for this program. The problem is, I don't fully understand arrays and how they work, so I'm a little lost. I will post my program I have written thus far so you can see what I'm working with, but I don't expect anyone to DO my assignment for me. I just need to know where to start and I'll try to go from there. I think I need to use a double array since I will be working with decimals since it deals with money, and my method call needs to calculate total price for all items entered by the user. Please help: RUNNING FILE package inventory2; import java.util.Scanner; public class RunApp { public static void main(String[] args) { Scanner input = new Scanner( System.in ); DataCollection theProduct = new DataCollection(); String Name = ""; double pNumber = 0.0; double Units = 0.0; double Price = 0.0; while(true) { System.out.print("Enter Product Name: "); Name = input.next(); theProduct.setName(Name); if (Name.equalsIgnoreCase("stop")) { return; } System.out.print("Enter Product Number: "); pNumber = input.nextDouble(); theProduct.setpNumber(pNumber); System.out.print("Enter How Many Units in Stock: "); Units = input.nextDouble(); theProduct.setUnits(Units); System.out.print("Enter Price Per Unit: "); Price = input.nextDouble(); theProduct.setPrice(Price); System.out.print("\n Product Name: " + theProduct.getName()); System.out.print("\n Product Number: " + theProduct.getpNumber()); System.out.print("\n Amount of Units in Stock: " + theProduct.getUnits()); System.out.print("\n Price per Unit: " + theProduct.getPrice() + "\n\n"); System.out.printf("\n Total cost for %s in stock: $%.2f\n\n\n", theProduct.getName(), theProduct.calculatePrice()); } } } DATA COLLECTION FILE package inventory2; public class DataCollection { String productName; double productNumber, unitsInStock, unitPrice, totalPrice; public DataCollection() { productName = ""; productNumber = 0.0; unitsInStock = 0.0; unitPrice = 0.0; } //setter methods public void setName(String name) { productName = name; } public void setpNumber(double pNumber) { productNumber = pNumber; } public void setUnits(double units) { unitsInStock = units; } public void setPrice(double price) { unitPrice = price; } //getter methods public String getName() { return productName; } public double getpNumber() { return productNumber; } public double getUnits() { return unitsInStock; } public double getPrice() { return unitPrice; } public double calculatePrice() { return (unitsInStock * unitPrice); } }

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  • Twisted + SQLAlchemy and the best way to do it.

    - by Khorkrak
    So I'm writing yet another Twisted based daemon. It'll have an xmlrpc interface as usual so I can easily communicate with it and have other processes interchange data with it as needed. This daemon needs to access a database. We've been using SQL Alchemy in place of hard coding SQL strings for our latest projects - those mostly done for web apps in Pylons. We'd like to do the same for this app and re-use library code that makes use of SQL Alchemy. So what to do? Well of course since that library was written for use in a Pylons app it's all the straight-forward blocking style code that everyone is accustomed to and all of the non-blocking is magically handled by Pylons via threading, thread locals, scoped sessions and so on. So now for Twisted I guess I'm a bit stuck. I could: Just write the sql I need directly if it's minimal and use the dbapi pool in twisted to do runInteractions etc when I need to hit the db. Use the objects and inherently blocking methods in our library and block now and then in my Twisted daemon. Bah. Use sAsync which was last updated in 2008 and kind of reuse the models we have defined already but not really and it does address code that needs to work in Pylons either. Does that even work with the latest version SQL Alchemy? Who knows. That project looked great though - why was it apparently abandoned? Spawn a separate subprocess and have it deal with the library code and all it's blocking, the results being returned back to my daemon when ready as objects marshalled via YAML over xmlrpc. Use deferToThread and then expunge the objects returned having made sure to do eager loads so that I have all my stuff that I might need. Seems kind of ugha to me. I'm also stuck using Python 2.5.4 atm so no 2.6 yet and I don't think I can just do an import from future to get access to the cool new multiprocessing module stuff in there. That's OK though I guess as we've got dealing with interprocess communication down pretty well. So I'm leaning towards option 4 mostly as that would avoid the mortal sin of logic duplication with option 1 while also staying the heck away from threads. Any better ideas?

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  • How can I link axes of imshow plots for zooming and panning?

    - by Adam Fraser
    Suppose I have a figure canvas with 3 plots... 2 are images of the same dimensions plotted with imshow, and the other is some other kind of subplot. I'd like to be able to link the x and y axes of the imshow plots so that when I zoom in one (using the zoom tool provided by the NavigationToolbar), the other zooms to the same coordinates, and when I pan in one, the other pans as well. Subplot methods such as scatter and histogram can be passed kwargs specifying an axes for sharex and sharey, but imshow has no such configuration. I started hacking my way around this by subclassing NavigationToolbar2WxAgg (shown below)... but there are several problems here. 1) This will link the axes of all plots in a canvas since all I've done is get rid of the checks for a.in_axes() 2) This worked well for panning, but zooming caused all subplots to zoom from the same global point, rather than from the same point in each of their respective axes. Can anyone suggest a workaround? Much thanks! -Adam from matplotlib.backends.backend_wxagg import NavigationToolbar2WxAgg class MyNavToolbar(NavigationToolbar2WxAgg): def __init__(self, canvas, cpfig): NavigationToolbar2WxAgg.__init__(self, canvas) # overrided # As mentioned in the code below, the only difference here from overridden # method is that this one doesn't check a.in_axes(event) when deciding which # axes to start the pan in... def press_pan(self, event): 'the press mouse button in pan/zoom mode callback' if event.button == 1: self._button_pressed=1 elif event.button == 3: self._button_pressed=3 else: self._button_pressed=None return x, y = event.x, event.y # push the current view to define home if stack is empty if self._views.empty(): self.push_current() self._xypress=[] for i, a in enumerate(self.canvas.figure.get_axes()): # only difference from overridden method is that this one doesn't # check a.in_axes(event) if x is not None and y is not None and a.get_navigate(): a.start_pan(x, y, event.button) self._xypress.append((a, i)) self.canvas.mpl_disconnect(self._idDrag) self._idDrag=self.canvas.mpl_connect('motion_notify_event', self.drag_pan) # overrided def press_zoom(self, event): 'the press mouse button in zoom to rect mode callback' if event.button == 1: self._button_pressed=1 elif event.button == 3: self._button_pressed=3 else: self._button_pressed=None return x, y = event.x, event.y # push the current view to define home if stack is empty if self._views.empty(): self.push_current() self._xypress=[] for i, a in enumerate(self.canvas.figure.get_axes()): # only difference from overridden method is that this one doesn't # check a.in_axes(event) if x is not None and y is not None and a.get_navigate() and a.can_zoom(): self._xypress.append(( x, y, a, i, a.viewLim.frozen(), a.transData.frozen())) self.press(event)

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  • Are comonads a good fit for modeling the Wumpus world?

    - by Tim Stewart
    I'm trying to find some practical applications of a comonad and I thought I'd try to see if I could represent the classical Wumpus world as a comonad. I'd like to use this code to allow the Wumpus to move left and right through the world and clean up dirty tiles and avoid pits. It seems that the only comonad function that's useful is extract (to get the current tile) and that moving around and cleaning tiles would not use be able to make use of extend or duplicate. I'm not sure comonads are a good fit but I've seen a talk (Dominic Orchard: A Notation for Comonads) where comonads were used to model a cursor in a two-dimensional matrix. If a comonad is a good way of representing the Wumpus world, could you please show where my code is wrong? If it's wrong, could you please suggest a simple application of comonads? module Wumpus where -- Incomplete model of a world inhabited by a Wumpus who likes a nice -- tidy world but does not like falling in pits. import Control.Comonad -- The Wumpus world is made up of tiles that can be in one of three -- states. data Tile = Clean | Dirty | Pit deriving (Show, Eq) -- The Wumpus world is a one dimensional array partitioned into three -- values: the tiles to the left of the Wumpus, the tile occupied by -- the Wumpus, and the tiles to the right of the Wumpus. data World a = World [a] a [a] deriving (Show, Eq) -- Applies a function to every tile in the world instance Functor World where fmap f (World as b cs) = World (fmap f as) (f b) (fmap f cs) -- The Wumpus world is a Comonad instance Comonad World where -- get the part of the world the Wumpus currently occupies extract (World _ b _) = b -- not sure what this means in the Wumpus world. This type checks -- but does not make sense to me. extend f w@(World as b cs) = World (map world as) (f w) (map world cs) where world v = f (World [] v []) -- returns a world in which the Wumpus has either 1) moved one tile to -- the left or 2) stayed in the same place if the Wumpus could not move -- to the left. moveLeft :: World a -> World a moveLeft w@(World [] _ _) = w moveLeft (World as b cs) = World (init as) (last as) (b:cs) -- returns a world in which the Wumpus has either 1) moved one tile to -- the right or 2) stayed in the same place if the Wumpus could not move -- to the right. moveRight :: World a -> World a moveRight w@(World _ _ []) = w moveRight (World as b cs) = World (as ++ [b]) (head cs) (tail cs) initWorld = World [Dirty, Clean, Dirty] Dirty [Clean, Dirty, Pit] -- cleans the current tile cleanTile :: Tile -> Tile cleanTile Dirty = Clean cleanTile t = t Thanks!

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