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  • How to store Hierarchical K-Means tree for a large number of images, using Opencv?

    - by AquaAsh
    I am trying to make a program that will find similar images from a dataset of images. The steps are 1)extract SURF descriptors for all images 2)store the descriptors 3)Apply knn on the stored descriptors 4)Match the stored descriptors to the query image descriptor using KNN Now each images SURF descriptor will be stored as Hierarchical k means tree, now do I store each tree as a separate file or is it possible to build some sort of single tree with all the images descriptors and updated as images are added to dataset. This is the paper I am basing the program on www.ijest.info/docs/IJEST10-02-03-13.pdf.

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  • How to have an excel addin read rows from a worksheet until no more data?

    - by user169867
    I've started writing a Com addin for Excel 2003 using C#. I'm looking for a code example showing how to read in cell data from the active worksheet. I've seen that you can write code like this: Excel.Range firstCell = ws.get_Range("A1", Type.Missing); Excel.Range lastCell = ws.get_Range("A10", Type.Missing); Excel.Range worksheetCells = ws.get_Range(firstCell, lastCell); to grab a range of cells. What I could use help with is how to read the cell data when you don't know how many rows of data there are. I may be able to determine the starting row that the data will be begin at, but there will be an unkown number of rows of data to read. Could someone provide me w/ an example of how to read rows from the worksheet until you come across a row of empty cells? Also does anyone know how to grab the range of cells the user has selected? Any help would be greatly appreciated. This seems like a powerful dev tool, but I'm having trouble finding detailed documentation to help me learn it :)

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  • C# slowdown while creating a bitmap - calculating distances from a large List of places for each pixel

    - by user576849
    I'm creating a graphic of the glow of lights above a geographic location based upon Walkers Law: Skyglow=0.01*Population*DistanceFromCenter^-2.5 I have a CSV file of places with 66,000 records using 5 fields (id,name,population,latitude,longitude), parsed on the FormLoad event and stored it in: List<string[]> placeDataList Then I set up nested loops to fill in a bitmap using SetPixel. For each pixel on the bitmap, which represents a coordinate on a map (latitude and longitude), the program loops through placeDataList – calculating the distance from that coordinate (pixel) to each place record. The distance (along with population) is used in a calculation to find how much cumulative sky glow is contributed to the coordinate from each place record. So, for every pixel, 66,000 distance calculations must be made. The problem is, this is predictably EXTREMELY slow – on the order of one line of pixels per 30 seconds or so on a 320 pixel wide image. This is unrelated to SetPixel, which I know is also slow, because the speed is similarly slow when adding the distance calculation results to an array. I don’t actually need to test all 66,000 records for every pixel, only the records within 150 miles (i.e. no skyglow is contributed to a coordinate from a small town 3000 miles away). But to find which records are within 150 miles of my coordinate I would still need to loop through all the records for each pixel. I can't use a smaller number of records because all 66,000 places contribute to skyglow for SOME coordinate in my map as it loops. This seems like a Catch-22, so I know there must be a better method out there. Like I mentioned, the slowdown is related to how many calculations I’m making per pixel, not anything to do with the bitmap. Any suggestions? private void fillPixels(int width) { Color pixelColor; int pixel_w = width; int pixel_h = (int)Math.Floor((width * 0.424088664)); Bitmap bmp = new Bitmap(pixel_w, pixel_h); for (int i = 0; i < pixel_h; i++) for (int j = 0; j < pixel_w; j++) { pixelColor = getPixelColor(i, j); bmp.SetPixel(j, i, pixelColor); } bmp.Save("Nightfall", System.Drawing.Imaging.ImageFormat.Jpeg); pictureBox1.Image = bmp; MessageBox.Show("Done"); } private Color getPixelColor(int height, int width) { int c; double glow,d,cityLat,cityLon,cityPop; double testLat, testLon; int size_h = (int)Math.Floor((size_w * 0.424088664)); ; testLat = (height * (24.443136 / size_h)) + 24.548874; testLon = (width * (57.636853 / size_w)) -124.640767; glow = 0; for (int i = 0; i < placeDataList.Count; i++) { cityPop=Convert.ToDouble(placeDataList[i][2]); cityLat=Convert.ToDouble(placeDataList[i][3]); cityLon=Convert.ToDouble(placeDataList[i][4]); d = distance(testLat, testLon, cityLat, cityLon,"M"); if(d<150) glow = glow+(0.01 * cityPop * Math.Pow(d, -2.5)); } if (glow >= 1) glow=1; c = (int)Math.Ceiling(glow * 255); return Color.FromArgb(c, c, c); }

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  • Double data entry system using Infopath 2007 how to compare 2 infopath documents for differences ?

    - by bugBurger
    How to compare 2 infopath documents craeted using double data entry system for differences ? We have a small project contains few infopath forms. Client is using double data entry system to reduce the errors. We are maintaining entry number in infopath form to seperate each entry. Note: I know we can compare xml data files of 2 documents. (xml data file has field names like field1,field2 and so on..while on form that field1 represent some meaninngful text) But the question is we want to compare it Visually side by side. Any difference should highlight the field.

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  • How can I use EF in windows forms to insert new data ?

    - by Al0NE
    Hi Maybe it's simple question, but it's my first time with EF + win app so ... I'm building win app with EF by adding edmx as data source then drag and drop the tables to get navigator and binding source .. when I press the add button in the navigator it allows me to enter new data but when I save the context I get NULL data for all fields except the auto increment field ( the ID field ).... What should I do to save many entries ...? DO I have to loop over all the entities in the binding source and add them to the context ?? Thanx in advance Update: I forgot to say that when i use data grid view it adds the items correctly but with "Details" it didn't ..

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  • I have a 18MB MySQL table backup. How can I restore such a large SQL file?

    - by Henryz
    I use a Wordpress plugin called 'Shopp'. It stores product images in the database rather than the filesystem as standard, I didn't think anything of this until now. I have to move server, and so I made a backup, but restoring the backup is proving a horrible task. I need to restore one table called wp_shopp_assets which is 18MB. Any advice is hugely appreciated. Thanks, Henry.

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  • how to animate a menu item into a large div (window) using jquery's animate?

    - by ijjo
    i'm pretty sure this can be done pretty easily with jquery's animate api, but i'm not good enough to figure it out. what i want to do is this: i have a menu item at the top of the viewport that the user will click on. when the user clicks on it, you'll see something that looks like the div "popping" out of the menu and float to a particular location on the screen. when i say popping i don't mean anything fancy - i just mean it appears to be originating from the menu item and settling somewhere on the screen that i specify. but the important part is that this animation happens really fast. fast enough where you don't have to actually wait for the window to appear, but slow enough so the eye sees the animation start from the menu item and end up at a new location where the window will actually appear, and appear with a specify height and width. hope that all made sense?

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  • When encrypting data that is not an even multiple of the block size do I have to send a complete las

    - by WilliamKF
    If I am using a block cipher such as AES which has a block size of 128 bits, what do I do if my data is not an even multiple of 128 bits? I am working with packets of data and do not want to change the size of my packet when encrypting it, yet my data is not an even multiple of 128? Does the AES block cipher allow handling of a final block that is short without changing the size of my message once encrypted?

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  • If I take a large datatype. Will it affect performance in sql server

    - by Shantanu Gupta
    If i takes larger datatype where i know i should have taken datatype that was sufficient for possible values that i will insert into a table will affect any performance in sql server in terms of speed or any other way. eg. IsActive (0,1,2,3) not more than 3 in any case. I know i must take tinyint but due to some reasons consider it as compulsion, i am taking every numeric field as bigint and every character field as nVarchar(Max) Please give statistics if possible, to let me try to overcoming that compulsion. I need some solid analysis that can really make someone rethink before taking any datatype.

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  • Django Problem - trying to access data entered into a form and feed it through a different page

    - by John Hoke
    OK, so let me give you an overview first. I have this site and in it there is a form section. When you access that section you can view or start a new project. Each project has 3-5 different forms. My problem is that I don't want viewers to have to go through all 3-5 pages to see the relevant information they need. Instead I want to give each project a main page where all the essential data entered into the forms is shown as non-editable data. I hope this makes sense. So I need to find a way to access all that data from the different forms for each project and to feed that data into the new page I'll be calling "Main". Each project will have a separate main page for itself. I'm pretty much clueless as to how I should do this, so any help at all would be appreciated. Thanks

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  • database design: table with large amount of columns (50+) or many sub tables with small amount of co

    - by Guillaume
    In our oroject we already have a lots of tables (100+). Some of them contains a lot of columns (50-100) and we are facing the need of adding more columns from time to time. What do you think is best - from maintenance and performance point of view - to split these huge tables in smaller entities or to keep the tables the way they are ? We are using an ORM tools, so we don't need to write custom request.

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  • How can I store large amount of data from a database to XML (speed problem, part three)?

    - by Andrija
    After getting some responses, the current situation is that I'm using this tip: http://www.ibm.com/developerworks/xml/library/x-tipbigdoc5.html (Listing 1. Turning ResultSets into XML), and XMLWriter for Java from http://www.megginson.com/downloads/ . Basically, it reads date from the database and writes them to a file as characters, using column names to create opening and closing tags. While doing so, I need to make two changes to the input stream, namely to the dates and numbers. // Iterate over the set while (rs.next()) { w.startElement("row"); for (int i = 0; i < count; i++) { Object ob = rs.getObject(i + 1); if (rs.wasNull()) { ob = null; } String colName = meta.getColumnLabel(i + 1); if (ob != null ) { if (ob instanceof Timestamp) { w.dataElement(colName, Util.formatDate((Timestamp)ob, dateFormat)); } else if (ob instanceof BigDecimal){ w.dataElement(colName, Util.transformToHTML(new Integer(((BigDecimal)ob).intValue()))); } else { w.dataElement(colName, ob.toString()); } } else { w.emptyElement(colName); } } w.endElement("row"); } The SQL that gets the results has the to_number command (e.g. to_number(sif.ID) ID ) and the to_date command (e.g. TO_DATE (sif.datum_do, 'DD.MM.RRRR') datum_do). The problems are that the returning date is a timestamp, meaning I don't get 14.02.2010 but rather 14.02.2010 00:00:000 so I have to format it to the dd.mm.yyyy format. The second problem are the numbers; for some reason, they are in database as varchar2 and can have leading zeroes that need to be stripped; I'm guessing I could do that in my SQL with the trim function so the Util.transformToHTML is unnecessary (for clarification, here's the method): public static String transformToHTML(Integer number) { String result = ""; try { result = number.toString(); } catch (Exception e) {} return result; } What I'd like to know is a) Can I get the date in the format I want and skip additional processing thus shortening the processing time? b) Is there a better way to do this? We're talking about XML files that are in the 50 MB - 250 MB filesize category.

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  • How could I use AJAX to create a Json data source .txt file?

    - by Adam
    I'm creating a form that collects standard information about customers. When the user hits save, I would like to create a .txt file that would be used to later retrieve all of the data collected from customers. I'm using DataTables which is a jQuery plugin to display the data. The .txt file would be formatted to be saved as such: { "aaData": [ ["client 1 name","address","city","state","zip"], ["client 2 name","address","city","state","zip"], ["client 3 name","address","city","state","zip"], ... ["client x name","address","city","state","zip"] ] } Where "aaData": is used by DataTables. This is going to part of an iPhone app, so the data source has to be very small and not reliant on a constant connection to a server, so, essentially, a client-side data source. The .txt file has to also be updated when edited and saved, and then replaced every time it is downloaded.

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  • Sql Server Compact Edition 3.5: Does the data persist in the database file?

    - by jerbersoft
    Hi guys, I have this question in which I have a SQL Server Compact Edition database for a desktop application. I am completely new to Sql Server Compact Edition. The question is, does the data inserted in the database persist even if the application is shut down or restarted? Coz I cant seem to find my data when using Sql Server Management Studio to manage the database. Am I missing anything/something? EDIT: Is SQL Server Compact Edition used for caching local data only? We cant use it like what we normally do on Sql Server Express for example managing data using Sql Server Management Studio?

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  • How to filter using a dropdown in Knockout

    - by user517406
    I have just started using Knockout and I want to filter my data that I am displaying in my UI by selecting an item from a dropdown. I have got so far, but I cannot get the selected value from my dropdown yet, and then after that I need to actually filter the data displayed based upon that value. Here is my code so far : @model Models.Fixture @{ ViewBag.Title = "Fixtures"; Layout = "~/Areas/Development/Views/Shared/_Layout.cshtml"; } @Scripts.Render("~/bundles/jqueryval") <script type="text/javascript" src="@Url.Content("~/Scripts/knockout-2.1.0.js")"></script> <script type="text/javascript"> function FixturesViewModel() { var self = this; var baseUri = '@ViewBag.ApiUrl'; self.fixtures = ko.observableArray(); self.teams = ko.observableArray(); self.update = function (fixture) { $.ajax({ type: "PUT", url: baseUri + '/' + fixture.Id, data: fixture }); }; self.sortByAwayTeamScore = function () { this.fixtures.sort(function(a, b) { return a.AwayTeamScore < b.AwayTeamScore ? -1 : 1; }); }; self.select = function (team) { }; $.getJSON("/api/fixture", self.fixtures); $.getJSON("/api/team", self.teams); } $(document).ready(function () { ko.applyBindings(new FixturesViewModel()); }); </script> <div class="content"> <div> <table><tr><td><select data-bind="options: teams, optionsText: 'TeamName', optionsCaption: 'Select...', optionsValue: 'TeamId', click: $root.select"> </select></td></tr></table> <table class="details ui-widget-content"> <thead> <tr><td>FixtureId</td><td>Season</td><td>Week</td><td>AwayTeam</td><td><a id="header" data-bind='click: sortByAwayTeamScore'>AwayTeamScore</a></td><td>HomeTeam</td><td>HomeTeamScore</td></tr> </thead> <tbody data-bind="foreach: fixtures"> <tr> <td><span data-bind="text: $data.Id"></span></td> <td><span data-bind="text: $data.Season"></span></td> <td><span data-bind="text: $data.Week"></span></td> <td><span data-bind="text: $data.AwayTeamName"></span></td> <td><input type="text" data-bind="value: $data.AwayTeamScore"/></td> <td><span data-bind="text: $data.HomeTeamName"></span></td> <td><input type="text" data-bind="value: $data.HomeTeamScore"/></td> <td><input type="button" value="Update" data-bind="click: $root.update"/></td> </tr> </tbody> </table> </div> </div> Can anybody please advise on this?

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  • import a text file into a temporary table using 'Load data infile' in a stored procedure- MySQL

    - by Pankaj
    I need to import a text file into a temporary table and from that select portions of it to insert in different tables. I wanted to use 'LOAD DATA INFILE'. Is there any way, i can use 'Load data infile' in a stored procedure. I am using mysql. LOAD DATA LOCAL INFILE 'C:\\MyData.txt' INTO TABLE tempprod fields terminated by ',' lines terminated by '\r\n'; SELECT * FROM product p;

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  • How to input test data using the DecisionTree module in python?

    - by lifera1n
    On the Python DescisionTree module homepage (DecisionTree-1.6.1), they give a piece of example code. Here it is: dt = DecisionTree( training_datafile = "training.dat", debug1 = 1 ) dt.get_training_data() dt.show_training_data() root_node = dt.construct_decision_tree_classifier() root_node.display_decision_tree(" ") test_sample = ['exercising=>never', 'smoking=>heavy', 'fatIntake=>heavy', 'videoAddiction=>heavy'] classification = dt.classify(root_node, test_sample) print "Classification: ", classification My question is: How can I specify sample data (test_sample here) from variables? On the project homepage, it says: "You classify new data by first constructing a new data vector:" I have searched around but have been unable to find out what a data vector is or the answer to my question. Any help would be appreciated!

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  • Can you use MongoDB map/reduce to migrate data?

    - by Brian Armstrong
    I have a large collection where I want to modify all the documents by populating a field. A simple example might be caching the comment count on each post: class Post field :comment_count, type: Integer has_many :comments end class Comment belongs_to :post end I can run it in serial with something like: Post.all.each do |p| p.udpate_attribute :comment_count, p.comments.count end But it's taking 24 hours to run (large collection). I was wondering if mongo's map/reduce could be used for this? But I haven't seen a great example yet. I imagine you would map off the comments collection and then store the reduced results in the posts collection. Am I on the right track?

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  • Fast inter-process (inter-threaded) communications IPC on large multi-cpu system.

    - by IPC
    What would be the fastest portable bi-directional communication mechanism for inter-process communication where threads from one application need to communicate to multiple threads in another application on the same computer, and the communicating threads can be on different physical CPUs). I assume that it would involve a shared memory and a circular buffer and shared synchronization mechanisms. But shared mutexes are very expensive (and there are limited number of them too) to synchronize when threads are running on different physical CPUs.

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