Search Results

Search found 45771 results on 1831 pages for 'java runtime environment'.

Page 827/1831 | < Previous Page | 823 824 825 826 827 828 829 830 831 832 833 834  | Next Page >

  • Find location using only distance and range?

    - by pinnacler
    Triangulation works by checking your angle to three KNOWN targets. "I know the that's the Lighthouse of Alexandria, it's located here (X,Y) on a map, and it's to my right at 90 degrees." Repeat 2 more times for different targets and angles. Trilateration works by checking your distance from three KNOWN targets. "I know the that's the Lighthouse of Alexandria, it's located here (X,Y) on a map, and I'm 100 meters away from that." Repeat 2 more times for different targets and ranges. But both of those methods rely on knowing WHAT you're looking at. Say you're in a forest and you can't differentiate between trees, but you know where key trees are. These trees have been hand picked as "landmarks." You have a robot moving through that forest slowly. Do you know of any ways to determine location based solely off of angle and range, exploiting geometry between landmarks? Note, you will see other trees as well, so you won't know which trees are key trees. Ignore the fact that a target may be occluded. Our pre-algorithm takes care of that. 1) If this exists, what's it called? I can't find anything. 2) What do you think the odds are of having two identical location 'hits?' I imagine it's fairly rare. 3) If there are two identical location 'hits,' how can I determine my exact location after I move the robot next. (I assume the chances of having 2 occurrences of EXACT angles in a row, after I reposition the robot, would be statistically impossible, barring a forest growing in rows like corn). Would I just calculate the position again and hope for the best? Or would I somehow incorporate my previous position estimate into my next guess? If this exists, I'd like to read about it, and if not, develop it as a side project. I just don't have time to reinvent the wheel right now, nor have the time to implement this from scratch. So if it doesn't exist, I'll have to figure out another way to localize the robot since that's not the aim of this research, if it does, lets hope it's semi-easy.

    Read the article

  • Android - Correspondence between ImageView coordinates and Bitmap Pixels

    - by Matteo
    In my application I want the user to be able to select some content of an Image contained inside an ImageView. To select the content I subclassed the ImageView class making it implement the OnTouchListener so to draw over it a rectangle with borders decided by the user. Here is an example of the result of the drawing (to have an idea you can think of it as when you click with the mouse on your desktop and drag the mouse): Now I need to determine which pixels of the Bitmap image correspond to the selected part. It's kind of easy to determine which are the points of the ImageView belonging to the rectangle, but I don't know how to get the correspondent pixels, since the ImageView has a different aspect ratio than the original image. I followed the approach described especially here, but also here, but am not fully satisfied because in my opinion the correspondence made is 1 on 1 between pixels and points on the ImageView and does not give me all the correspondent pixels on the original image to the selected area. Calling hoveredRect the rectangle on the ImageView the points inside of it are: class Point { float x, y; @Override public String toString() { return x + ", " + y; } } Vector<Point> pointsInRect = new Vector<Point>(); for( int x = hoveredRect.left; x <= hoveredRect.right; x++ ){ for( int y = hoveredRect.top; y <= hoveredRect.bottom; y++ ){ Point pointInRect = new Point(); pointInRect.x = x; pointInRect.y = y; pointsInRect.add(pointInRect); } } How can I obtain a Vector<Pixels> pixelsInImage containing the correspondent pixels?

    Read the article

  • Ivy failed to resolve dependency : What to check, what to do ?

    - by fardon57
    Hi everyone, I'm using Ivy to resolve dependency in my very small project. It's the first time I'm doing that and it's more to learn as my project is very small. I had a problem 5 minutes ago, when trying to download log4j. My configuration is very basic, I have an ant task : <target name="resolve" description="--> retrieve dependencies with ivy"> <ivy:retrieve/> </target> and my Ivy.xml file is like this : <dependency org="javax.servlet" name="servlet-api" rev="2.5" /> <dependency org="log4j" name="log4j" rev="1.2.15" /> </dependencies> The problem is seems to happen when ivy tries to download jms 1.1 (I suppose it's needed for log4j) as I can see in the console : : ::::::::::::::::::::::::::::::::::::::::::::: [ivy:retrieve] :: FAILED DOWNLOADS :: [ivy:retrieve] :: ^ see resolution messages for details ^ :: [ivy:retrieve] :::::::::::::::::::::::::::::::::::::::::::::: [ivy:retrieve] :: javax.jms#jms;1.1!jms.jar [ivy:retrieve] :: com.sun.jdmk#jmxtools;1.2.1!jmxtools.jar [ivy:retrieve] :: com.sun.jmx#jmxri;1.2.1!jmxri.jar [ivy:retrieve] :::::::::::::::::::::::::::::::::::::::::::::: Is there anything I can do ? Thanks a lot guys. F

    Read the article

  • Parsing line and selecting values corresponding to a key

    - by gagneet
    there is a set of data which is arranged in a specific manner (as a tree), as is given below. basically a key=value pair, with some additional values at the end, which informs how many children does the branch have and some junk value. 11=1 123 2 11=1>1=45 234 1 11=1>1=45>9=16 345 1 11=1>1=45>9=16>2=34 222 1 11=1>1=45>9=16>2=34>7=0 2234 1 11=1>1=45>9=16>2=34>7=0>8=0 22345 1 11=1>1=45>9=16>2=34>7=0>8=0>0=138 22234 1 11=1>1=45>9=16>2=34>7=0>8=0>0=138>5=0 5566 1 11=1>1=45>9=16>2=34>7=0>8=0>0=138>5=0>4=0 664 1 11=1>1=45>9=16>2=34>7=0>8=0>0=138>5=0>4=0>6=10 443 1 11=1>1=45>9=16>2=34>7=0>8=0>0=138>5=0>4=0>6=10>3=11 445 0 11=1>1=47 4453 1 11=1>1=47>9=16 887 1 11=1>1=47>9=16>2=34 67 1 11=1>1=47>9=16>2=340>7=0 98 1 11=1>1=47>9=16>2=34>7=0>8=0 654 1 11=1>1=47>9=16>2=34>7=0>8=0>0=138 5789 1 11=1>1=47>9=16>2=34>7=0>8=0>0=138>5=0 9870 1 11=1>1=47>9=16>2=34>7=0>8=0>0=138>5=0>4=0 3216 1 11=1>1=47>9=16>2=34>7=0>8=0>0=138>5=0>4=0>6=10>3=11 66678 0 my problem is to get the appropriate branch from the above data, which satisfies exactly the values, which i give as the input. suppose, my input value to search in the above data stack are: 5=0 4=0 6=10 3=11 11=1 1=45 0=138 9=16 2=34 7=0 8=0 for the above given list of key-values, the function should return 11=11=459=162=347=08=00=1385=04=06=103=11 as the match. likewise, for another input file, in which another set of keys is given: 5=0 4=0 6=10 3=11 11=1 1=45 9=16 2=34 7=0 8=0 the function should return 11=11=459=162=347=08=0 1 as the match. not the last line; as that would also match all the values given in my input key, but, i want only the exact match. Also, I want to find out how many nodes were selected in the given array. (separated by ). What will be the best way to implement this kind of scenario?

    Read the article

  • Best practice for DAO pattern ?

    - by Tony
    I've seen a lot of codes use a service-dao pattern , I don't know the origin of this pattern . It force the front layer call service , then delegates some of the service task to dao. I want to ask : Does DAO layer do purely data access related task ? What about exception encapsulation ? Is there other pattern can be used to replace this ?

    Read the article

  • Creating a bitmask parameter for a function or method

    - by synic
    I noticed a lot of Android functions have a parameter that you can pass in that's a bitmask, for different options, like on PendingIntent, you can pass in things like you can call getActivity() with PendingIntent.FLAG_CANCEL_CURRENT|PendingIntent.FLAG_NO_CREATE. I'm wondering how I can create a function that has a parameter like this?

    Read the article

  • Spring MVC with a rich client framework

    - by ziggy
    I have several applications that are structured as follows DataComponent WebComponent ThickClientComponent WebServices The DataComponent has all the functionality required to access the application's data so it contains the DAOs and the JPA entities. The other three modules are: WebComponent - A spring MVC application that uses the DataComponent for data acccess ThickClientComponent- A Swing application that uses the DataComponent for data access WebServices - A SOAP based services that also uses the DataComponent. All three projets have the DataComponent as a dependeny in their Maven POM file. I would like to use a rich client framework like RichFaces, icefaces or primefaces as i need to be able to use the rich components are available in rich client frameworks (i.e. trees, panel, drag and drop etc). I have looked around and i cant seem to find an example where a Spring MVC application uses a rich client platform. Is it possible? Are the rich client platforms a framework meaning that i have to use either Spring MVC or the rich client platform but not both? The DataComponent module is spring based.

    Read the article

  • How to keep the session of user login?

    - by YaW
    Hi, I have an app that requires user to register. I've got the app conected to PHP in my server to do the logic of register/login and so, this is not problem at all. But, I want to keep a session of the user in local, so the user doesn't have to login again every time he runs the app. So, I want something like this: First time user, he opens the app, register and login. Do some stuff with the app and closes it. Open the app again, the user is recognized so he doesn't need to login again. I only need to store an ID and a Username (both fetched from the DB in the login php method). What's the best way to do this?? I've thought about doing a custom preference, store the data in files or even a local DB (sqlite). Any suggestions?

    Read the article

  • How can i take only integer input from keyboard and if input is invalid how do i ask user agaian

    - by fari
    This is what i have written so far but when exception is raised it does not again ask teh user for input. do{ System.out.println("Enter the number of stones to play with: "); BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String temp=br.readLine(); }while (key<0 && key>9); if(key<0 || key>10) throw new InvalidStartingStonesException(key); player1=new KeyBoardPlayer(); player2 = new KeyBoardPlayer(); this.player1=player1; this.player2=player2; state=new KalaGameState(key); } catch(NumberFormatException nFE) { System.out.println("Not an Integer");} catch(IOException e) { System.out.println(e); }

    Read the article

  • HttpURLConnection: What's the deal with having to read the whole response?

    - by stormin986
    My current problem is very similar to this one. I have a downloadFile(URL) function that creates a new HttpURLConnection, opens it, reads it, returns the results. When I call this function on the same URL multiple times, the second time around it almost always returns a response code of -1 (But throws no exception!!!). The top answer in that question is very helpful, but there are a few things I'm trying to understand. So, if setting http.keepAlive to false solves the problem, it indicates what exactly? That the server is responding in a way that violates the http protocol? Or more likely, my code is violating the protocol in some way? What will the trace tell me? What should I look for? And what's the deal with this: You need to read everything from error stream. Otherwise, it's going to confuse next connection and that's the cause of -1. Does this mean if the response is some type of error (which would be what response code(s)?), the stream HAS to be fully read? Also, every time I am attempting an http request I am basically creating a new connection, and then disconnect()ing it at the end. However, in my case I'm not getting a 401 or whatever. It's always a 200. But my second connection almost always fails. Does this mean there's some other data I should be reading that I'm not (in a similar manner that the error stream must be fully read)? Please help shed some light on this? I feel like there's some fundamental http protocol understanding I'm missing.

    Read the article

  • Creating method templates in Eclipse

    - by stevebot
    Is there any way to do the following in eclipse? Have eclipse template a method like the following public void test(){ // CREATE MOCKS // CREATE EXPECTATIONS // REPLAY MOCKS // VERIFY MOCKS } so then I could presumably just use intellisense and select an option like "createtest" and have it stub out a method with the comments similar to the above?My problem is that often myself and other developers I know forgot all the steps we need to follow to do what we dub as a valid unit test for our application. If I could template our test methods to stub out the comments above it would be a big help.

    Read the article

  • JPA optimistic lock - setting @Version to entity class cause query to include VERSION as column

    - by masato-san
    I'm using JPA Toplink Essential, Netbean6.8, GlassFish v3 In my Entity class I added @Version annotation to enable optimistic locking at transaction commit however after I added the annotation, my query started including VERSION as column thus throwing SQL exception. None of this is mentioned in any tutorial I've seen so far. What could be wrong? Snippet public class MasatosanTest2 implements Serializable { private static final long serialVersionUID = 1L; @Id @Basic(optional = false) @Column(name = "id") private Integer id; @Column(name = "username") private String username; @Column(name = "note") private String note; //here adding Version @Version int version; query used: SELECT m FROM MasatosanTest2 m Internal Exception: com.microsoft.sqlserver.jdbc.SQLServerException Call: SELECT id, username, note, VERSION FROM MasatosanTest2

    Read the article

  • how to Update JTable

    - by bob3333
    Good evening I have a JTable that I built with a TableModel how to update the elements of the table, because when I do table = new JTable (new TableProg (elementTab)) I create another table above the original table and it is very ugly So for example how to update element of table in a loop at each iteration as "elementTab" changes? thank you very much

    Read the article

  • Powermock Slows Down Test Startup on Eclipse/Fedora 10 when on NTFS partition

    - by MrWiggles
    I've just started having a proper play with Powermock and noticed that it slows down test startup immensely. A quick look at top while it was running shows that mount.nfts-3g was taking up most of the CPU. I moved Eclipse and my source directory to ext3 partitions to see if that was a problem and the tests now startup quicker but there's still a noticeable delay. Is this normal with Powermock or am I missing something obvious?

    Read the article

  • How to configure MySQL connection properties with Spring, Hibernate 3.3 and c3p0?

    - by sfussenegger
    I am currently in the process of upgrading an application from Hibernate 3.2 to Hibernate 3.3. I though I'd stick with the default connection pool (Hibernate changed its default from Commons DBCP to c3p0) as I don't have any good reason to choose a non-default pool. At least non but having used DBCP before. The upgrade went pretty much without any problems so far. The only thing I can't get to work is passing properties to the underlying MySQL JDBC4Connection. Up to now, I used DBCP's BasicDataSource.addConnectionProperty(String,String) to pass properties (useUnicode=true, characterEncodin=UTF-8, characterSetResults=UTF-8, zeroDateTimeBehavior=convertToNull). However, I can't find any way to do the same with c3p0 other than including them in the JDBC URL. (That's something I'd like to avoid as I wanna keep the URL configurable without forcing users to include those parameters.) So far, I've tried to use a ConnectionCustomizer without success. Any other suggestions?

    Read the article

  • Guide to Learn J2ME

    - by Sopolin
    Hi all, I am starting study java2me. But I have some source study about it like ebook, source sample code, and ... Could anybody give some link website or source ebook study about it. Thanks, Sopolin

    Read the article

  • How to determine which source files are required for an Eclipse run configuration

    - by isme
    When writing code in an Eclipse project, I'm usually quite messy and undisciplined in how I create and organize my classes, at least in the early hacky and experimental stages. In particular, I create more than one class with a main method for testing different ideas that share most of the same classes. If I come up with something like a useful app, I can export it to a runnable jar so I can share it with friends. But this simply packs up the whole project, which can become several megabytes big if I'm relying on large library such as httpclient. Also, if I decide to refactor my lump of code into several projects once I work out what works, and I can't remember which source files are used in a particular run configuration, all I can do it copy the main class to a new project and then keep copying missing types till the new project compiles. Is there a way in Eclipse to determine which classes are actually used in a particular run configuration? EDIT: Here's an example. Say I'm experimenting with web scraping, and so far I've tried to scrape the search-result pages of both youtube.com and wrzuta.pl. I have a bunch of classes that implement scraping in general, a few that are specific to each of youtube and wrzuta. On top of this I have a basic gui common to both scrapers, but a few wrzuta- and youtube-specific buttons and options. The WrzutaGuiMain and YoutubeGuiMain classes each contain a main method to configure and show the gui for each respective website. Can Eclipse look at each of these to determine which types are referenced?

    Read the article

  • red black tree balancing?

    - by Anirudh Kaki
    i am working to generate tango tree, where i need to check whether every sub tree in tango is balanced or not. if its not balanced i need to make it balance? I trying so hard to make entire RB-tree balance but i not getting any proper logic so can any one help me out?? here i am adding code to check how to find my tree is balanced are not but when its not balanced how can i make it balance. static boolean verifyProperty5(rbnode n) { int left = 0, right = 0; if (n != null) { bh++; left = blackHeight(n.left, 0); right = blackHeight(n.right, 0); } if (left == right) { System.out.println("black height is :: " + bh); return true; } else { System.out.println("in balance"); return false; } } public static int blackHeight(rbnode root, int len) { bh = 0; blackHeight(root, path1, len); return bh; } private static void blackHeight(rbnode root, int path1[], int len) { if (root == null) return; if (root.color == "black"){ root.black_count = root.parent.black_count+1; } else{ root.black_count = root.parent.black_count; } if ((root.left == null) && (root.right == null)) { bh = root.black_count; } blackHeight(root.left, path1, len); blackHeight(root.right, path1, len); }

    Read the article

< Previous Page | 823 824 825 826 827 828 829 830 831 832 833 834  | Next Page >