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  • Creating an SQL variable character column > 255 characters supporting multiple databases

    - by Piers
    I have an application that stores data through an ODBC data source of the user's choosing. So far it has worked well on a range of database systems (e.g. JET, Oracle, SQL Server), as the SQL syntax is fairly simple. Now I am running into a problem where I need to store more than 255 characters in my strings. Previously I created the table using column type VARCHAR (255). Now if I try to create a table using, e.g. VARCHAR (512) then it falls over on Access databases. I know that I can use the MEMO type for Access, but this is non-standard SQL and will thus likely fail on other database systems (e.g. Oracle). Is there any widely supported SQL standard for creating text columns wider than 255 characters, or do I need to find another solution? The alternatives seem to me to be: 1) Profile the database system and customise the SQL CREATE TABLE command based on the database system. I don't like this as it defeats the purpose of using ODBC. 2) Add extra columns of 255 chars as required (e.g. LONGSTRING1, LONGSTRING2, ...) and concatenate after reading. I don't like this because it means the number of columns can vary between tables and it complicates read/write. Are there any other viable alternatives to these two options? Or is it possible to have an SQL compliant CREATE TABLE command supported by the majority of database vendors, that supports strings longer than 255 chars?

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  • MySQL Stored Procedures not working with SELECT (basic question)

    - by TMG
    Hello, I am using a platform (perfectforms) that requires me to use stored procedures for most of my queries, and having never used stored procedures, I can't figure out what I'm doing wrong. The following statement executes without error: DELIMITER // DROP PROCEDURE IF EXISTS test_db.test_proc// CREATE PROCEDURE test_db.test_proc() SELECT 'foo'; // DELIMITER ; But when I try to call it using: CALL test_proc(); I get the following error: #1312 - PROCEDURE test_db.test_proc can't return a result set in the given context I am executing these statements from within phpmyadmin 3.2.4, PHP Version 5.2.12 and the mysql server version is 5.0.89-community. When I write a stored procedure that returns a parameter, and then select it, things work fine (e.g.): DELIMITER // DROP PROCEDURE IF EXISTS test_db.get_sum// CREATE PROCEDURE test_db.get_sum(out total int) BEGIN SELECT SUM(field1) INTO total FROM test_db.test_table; END // DELIMITER ; works fine, and when I call it: CALL get_sum(@t); SELECT @t; I get the sum no problem. Ultimately, what I need to do is have a fancy SELECT statement wrapped up in a stored procedure, so I can call it, and return multiple rows of multiple fields. For now I'm just trying to get any select working. Any help is greatly appreciated.

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  • clojure: ExceptionInInitializerError in Namespace.<init> loading from a non-default classpath

    - by Charles Duffy
    In attempting to load an AOT-compiled class from a non-default classpath, I receive the following exception: Traceback (innermost last): File "test.jy", line 10, in ? at clojure.lang.Namespace.<init>(Namespace.java:34) at clojure.lang.Namespace.findOrCreate(Namespace.java:176) at clojure.lang.Var.internPrivate(Var.java:149) at aot_demo.JavaClass.<clinit>(Unknown Source) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:247) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) java.lang.ExceptionInInitializerError: java.lang.ExceptionInInitializerError I'm able to reproduce this with the following trivial project.clj: (defproject aot-demo "0.1.0-SNAPSHOT" :dependencies [[org.clojure/clojure "1.3.0"]] :aot [aot-demo.core]) ...and src/aot_demo/core.clj defined as follows: (ns aot-demo.core (:gen-class :name aot_demo.JavaClass :methods [#^{:static true} [lower [java.lang.String] java.lang.String]])) (defn -lower [str] (.toLower str)) The following Jython script is then sufficient to trigger the bug: #!/usr/bin/jython import java.lang.Class import java.net.URLClassLoader import java.net.URL import os cl = java.net.URLClassLoader( [java.net.URL('file://%s/target/aot-demo-0.1.0-SNAPSHOT-standalone.jar' % (os.getcwd()))]) java.lang.Class.forName('aot_demo.JavaClass', True, cl) However, the exception does not occur if the test script is started with the uberjar already in the CLASSPATH variable. What's going on here? I'm trying to write a plugin for the BaseX database in Clojure; the above accurately represents how their plugin-loading mechanism works for the purpose of providing a SSCE for this problem.

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  • Delphi Unicode String Type Stored Directly at its Address (or "Unicode ShortString")

    - by Andreas Rejbrand
    I want a string type that is Unicode and that stores the string directly at the adress of the variable, as is the case of the (Ansi-only) ShortString type. I mean, if I declare a S: ShortString and let S := 'My String', then, at @S, I will find the length of the string (as one byte, so the string cannot contain more than 255 characters) followed by the ANSI-encoded string itself. What I would like is a Unicode variant of this. That is, I want a string type such that, at @S, I will find a unsigned 32-bit integer (or a single byte would be enough, actually) containing the length of the string in bytes (or in characters, which is half the number of bytes) followed by the Unicode representation of the string. I have tried WideString, UnicodeString, and RawByteString, but they all appear only to store an adress at @S, and the actual string somewhere else (I guess this has do do with reference counting and such). Update: The most important reason for this is probably that it would be very problematic if sizeof(string) were variable. I suspect that there is no built-in type to use, and that I have to come up with my own way of storing text the way I want (which actually is fun). Am I right? Update I will, among other things, need to use these strings in packed records. I also need manually to read/write these strings to files/the heap. I could live with fixed-size strings, such as <= 128 characters, and I could redesign the problem so it will work with null-terminated strings. But PChar will not work, for sizeof(PChar) = 1 - it's merely an address. The approach I eventually settled for was to use a static array of bytes. I will post my implementation as a solution later today.

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  • JavaScript: Achieving precise animation end values?

    - by bobthabuilda
    I'm currently trying to write my own JavaScript library. I'm in the middle of writing an animation callback, but I'm having trouble getting precise end values, especially when animation duration times are smaller. Right now, I'm only targeting positional animation (left, top, right, bottom). When my animations complete, they end up having an error margin of 5px~ on faster animations, and 0.5px~ on animations 1000+ ms or greater. Here's the bulk of the callback, with notes following. var current = parseFloat( this[0].style[prop] || 0 ) // If our target value is greater than the current , gt = !!( value > current ) , delta = ( Math.abs(current - value) / (duration / 13) ) * (gt ? 1 : -1) , elem = this[0] , anim = setInterval( function(){ elem.style[prop] = ( current + delta ) + 'px'; current = parseFloat( elem.style[prop] ); if ( gt && current >= value || !gt && current <= value ) clearInterval( anim ); }, 13 ); this[0] and elem both reference the target DOM element. prop references the property to animate, left, top, bottom, right, etc. current is the current value of the DOM element's property. value is the desired value to animate to. duration is the specified duration (in ms) that the animation should last. 13 is the setInterval delay (which should roughly be the absolute minimal for all browsers). gt is a var that is true if value exceeds the initial current, else it is false. How can I resolve the error margin?

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  • How to Capture a live stream from Windows Media Server 2008 using c#.net

    - by Hummad Hassan
    I want to capture the live stream from windows media server to filesystem on my pc I have tried with my own media server with the following code. but when i have checked the out put file i have found this in it. please help me with this. Thanks [Reference] Ref1=http://mywindowsmediaserver/test?MSWMExt=.asf Ref2=http://mywindowsmediaserver/test?MSWMExt=.asf FileStream fs = null; try { HttpWebRequest req = (HttpWebRequest)WebRequest.Create("http://mywmsserver/test"); CookieContainer ci = new CookieContainer(1000); req.Timeout = 60000; req.Method = "Get"; req.KeepAlive = true; req.MaximumAutomaticRedirections = 99; req.UseDefaultCredentials = true; req.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3"; req.ReadWriteTimeout = 90000000; req.CookieContainer = ci; //req.MediaType = "video/x-ms-asf"; req.AllowWriteStreamBuffering = true; HttpWebResponse resp = (HttpWebResponse)req.GetResponse(); Stream resps = resp.GetResponseStream(); fs = new FileStream("d:\\dump.wmv", FileMode.Create, FileAccess.ReadWrite); byte[] buffer = new byte[1024]; int bytesRead = 0; while ((bytesRead = resps.Read(buffer, 0, buffer.Length)) > 0) { fs.Write(buffer, 0, bytesRead); } } catch (Exception ex) { } finally { if (fs != null) fs.Close(); }

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  • SQL: Need help with query construction.

    - by Geeknidas
    Hi Guys, I am relatively new with sql and I need some help with some basic query construction. Problem: To retrieve the number of orders and the customer id from a table based on a set of parameters. I want to write a query to figure out the number of orders under each customer (Column: Customerid) along with the CustomerID where the number of orders should be greater or equal to 10 and the status of the order should be Active. Moreover, I also want to know the first transaction date of an order belonging to each customerid. Table Description: product_orders Orderid CustomerId Transaction_date Status ------- ---------- ---------------- ------- 1 23 2-2-10 Active 2 22 2-3-10 Active 3 23 2-3-10 Deleted 4 23 2-3-10 Active Query that I have written: select count(*), customerid from product_orders where status = 'Active' GROUP BY customerid ORDER BY customerid; The above statement gives me the sum of all order under a customer id but does not fulfil the condition of atleast 10 orders. I donot know how to display the first transaction date along with the order under a customerid (status: could be active or delelted doesn't matter) Ideal solutions should look like: Total Orders CustomerID Transaction Date (the first transaction date) ------------ ---------- ---------------- 11 23 1-2-10 Thanks in advance. I hope you guys would be kind enough to stop by and help me out. Cheers, Leonidas

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  • php: replacing double <br /> with </p><p>

    - by andufo
    i use nicEdit to write RTF data in my CMS. The problem is that it generates strings like this: hello first line<br><br />this is a second line<br />this is a 3rd line since this is for a news site, i much prefer the final html to be like this: <p>hello first line</p><p>this is a second line<br />this is a 3rd line</p> so my current solution is this: i need to trim the $data for <br /> at the start/end of the string replace <br /><br /> with </p><p> (one single <br /> is allowed). finally, add <p> at the start and </p> at the end i only have the 3rd step so far. can someone give me a hand with steps 1 and 2? function replace_br($data) { # step 3 $data = '<p>'.$data.'</p>'; return $data; } thanks! ps: it would be even better to avoid specific situations. example: "hello<br /><br /><br /><br /><br />too much space" -- those 5 breaklines should also be converted to just one "</p><p>"

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  • How Can I Create Reports in a Custom C#.NET Windows Application? - General Question

    - by user311509
    Assume i have a custom Windows application written in C#. This application has only the following functionalists, add, edit, delete and view. For example, a user can add a sale, change sales record, delete a sale record or view the whole sales record. I need to add some reporting functionalists e.g. i want a user to print the sales of a certain customer from 2008 to 2009 into pdf, what all products a certain customer has purchased from us and so on. I will only include the basic common report requests that are usually needed in the office. Any other kind of reports that are requested inconsistently, i would do it manually from my side at the back end and send the results manually to the requester. What i would do is: If a user wants more info of a certain customer, a special window box appears for that customer. This window box will have different controls that allows user to request more info such as, print customer purchases from ..... to ..... (user chooses the dates) and user will view results in pdf or so. Of course, at the back scene i will write an appropriate SQL Query with parameters that meets a certain function. Is this how it should be done? I have heard about SQL Reporting, i don't know anything about it yet. I will check it out. Anyhow, your suggestions won't harm. I'm still a student, so i don't have practical experience yet. I hope my question is clear enough. Thank you.

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  • Nothing gets displayed when debugging Microsoft Surface

    - by leftend
    I am trying to write my first Microsoft Surface application, and am doing the development on the Surface unit itself. I successfully re-created the quick "Photos" application that is shown on the PDC Video, however, now that I'm trying to create my own app - nothing actually shows up when I run it. I'm mainly just adding ScatterViews right now - and they show up fine in the designer, but as soon as I hit F5 - the shell is shown on the surface - but none of the ScatterViews show up. Here's my xaml code so far. Am I missing something?? <s:SurfaceWindow x:Class="SurfaceUITreeDemo.TreeDemo" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:s="http://schemas.microsoft.com/surface/2008" Title="WYITT Tree Demo" AllowsTransparency="False" Background="Beige"> <s:SurfaceWindow.Resources> <ImageBrush x:Key="WindowBackground" Stretch="None" Opacity="0.6" ImageSource="pack://application:,,,/Resources/TreeDemoBackground.jpg"/> </s:SurfaceWindow.Resources> <Grid Background="{StaticResource WindowBackground}" > <s:ScatterView Name="test"> <Image Source="C:\dev\Network-Alt-icon.png"/> </s:ScatterView> <s:ScatterView Height="100" Margin="456,160,348,0" Name="scatterView1" VerticalAlignment="Top" Background="Black"> <s:ScatterViewItem Height="100" Width="150"> <Image Source="C:\dev\Network-Alt-icon.png"/> </s:ScatterViewItem> <s:ScatterViewItem></s:ScatterViewItem> ScatterView </s:ScatterView> </Grid> </s:SurfaceWindow>

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  • Raising C# events with an extension method - is it bad?

    - by Kyralessa
    We're all familiar with the horror that is C# event declaration. To ensure thread-safety, the standard is to write something like this: public event EventHandler SomethingHappened; protected virtual void OnSomethingHappened(EventArgs e) { var handler = SomethingHappened; if (handler != null) handler(this, e); } Recently in some other question on this board (which I can't find now), someone pointed out that extension methods could be used nicely in this scenario. Here's one way to do it: static public class EventExtensions { static public void RaiseEvent(this EventHandler @event, object sender, EventArgs e) { var handler = @event; if (handler != null) handler(sender, e); } static public void RaiseEvent<T>(this EventHandler<T> @event, object sender, T e) where T : EventArgs { var handler = @event; if (handler != null) handler(sender, e); } } With these extension methods in place, all you need to declare and raise an event is something like this: public event EventHandler SomethingHappened; void SomeMethod() { this.SomethingHappened.RaiseEvent(this, EventArgs.Empty); } My question: Is this a good idea? Are we missing anything by not having the standard On method? (One thing I notice is that it doesn't work with events that have explicit add/remove code.)

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  • How should I generate the partitions / pairs for the Chinese Postman problem?

    - by Simucal
    I'm working on a program for class that involves solving the Chinese Postman problem. Our assignment only requires us to write a program to solve it for a hard-coded graph but I'm attempting to solve it for the general case on my own. The part that is giving me trouble is generating the partitions of pairings for the odd vertices. For example, if I had the following labeled odd verticies in a graph: 1 2 3 4 5 6 I need to find all the possible pairings / partitions I can make with these vertices. I've figured out I'll have i paritions given: n = num of odd verticies k = n / 2 i = ((2k)(2k-1)(2k-2)...(k+1))/2 So, given the 6 odd verticies above, we will know that we need to generate i = 15 partitions. The 15 partions would look like: 1 2 3 4 5 6 1 2 3 5 4 6 1 2 3 6 4 5 ... 1 6 ... Then, for each partition, I take each pair and find the shortest distance between them and sum them for that partition. The partition with the total smallest distance between its pairs is selected, and I then double all the edges between the shortest path between the odd vertices (found in the selected partition). These represent the edges the postman will have to walk twice. At first I thought I had worked out an appropriate algorithm for generating these partitions / pairs but it is flawed. I found it wasn't a simple permutation/combination problem. Does anyone who has studied this problem before have any tips that can help point me in the right direction for generating these partitions?

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  • multithreading issue

    - by vbNewbie
    I have written a multithreaded crawler and the process is simply creating threads and having them access a list of urls to crawl. They then access the urls and parse the html content. All this seems to work fine. Now when I need to write to tables in a database is when I experience issues. I have 2 declared arraylists that will contain the content each thread parse. The first arraylist is simply the rss feed links and the other arraylist contains the different posts. I then use a for each loop to iterate one while sequentially incrementing the other and writing to the database. My problem is that each time a new thread accesses one of the lists the content is changed and this affects the iteration. I tried using nested loops but it did not work before and this works fine using a single thread.I hope this makes sense. Here is my code: SyncLock dlock For Each l As String In links finallinks.Add(l) Next End SyncLock SyncLock dlock For Each p As String In posts finalposts.Add(p) Next End SyncLock ... Dim i As Integer = 0 SyncLock dlock For Each rsslink As String In finallinks postlink = finalposts.Item(i) i = i + 1 finallinks and finalposts are the two arraylists. I did not include the rest of the code which shows the threads working but this is the essential part where my error occurs which is basically here postlink = finalposts.Item(i) i = i + 1 ERROR: index was out of range. Must be non-negative and less than the size of the collection Is there an alternative?

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  • Quitting an application - is that frowned upon?

    - by Ted
    Moving on in my attempt to learn Android I just read the following: Question: Does the user have a choice to kill the application unless we put a menu option in to kill it? If no such option exists, how does the user terminate the application? Answert (Romain Guy): The user doesn't, the system handles this automatically. That's what the activity lifecycle (especially onPause/onStop/onDestroy) is for. No matter what you do, do not put a "quit" or "exit" application button. It is useless with Android's application model. This is also contrary to how core applications work. Hehe, for every step I take in the Android world I run into some sort of problem =( Apparently, you cannot quit an application in Android (but Android can very well totally destroy your app whenever it feels like it). Whats up with that? I am starting to think that its impossible to write an app that functions as a "normal app" - that the user can quit the app when he/she decides to do so. That is not something that should be relied upon the OS to do. The application I am trying to create is not an application for the Android Market. It is not an application for "wide use" by the general public, it is a business app that is going to be used in a very narrow business field. I was actually really looking forward to developing for the Android-platform, since it addresses a lot of issues that exist in Windows Mobile and .NET. However, the last week has been somewhat of a turnoff for me... I hope I dont have to abandon Android, but it doesnt look very good right now =( Is there a way for me to really quit the application?

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  • Quartz 2D or OpenGL ES? Pros and cons in the long term, possibility of migration to other platforms.

    - by fspirit
    Hi all! I'm having a hard time deciding whether to go with Quartz2D or OpenGL for an iPad game. It will be 2D mostly, but effect-intense (simultaneous lighting effects for 10-30 objects, 10-20 simultaneous animations on the screen). So far, assuming i'm equally dumb in both technologies and have to learn them from the ground, i came to this list. (I've read several topics here, on SO, with names like "Quartz or OpenGL", but i'm still left with some questions) Quartz: Better time-to-market, because of ready to use absractions like UIView, UIImageView, CoreAnimation abstractions Open GL ES Closer to hardware, thus, performance is better. App, implemented with OpenGL ES can be easier migrated to Android, MeeGo, Windows Phone, etc. My questions are: How time will it take to rewrite Quartz 2d app to use OpenGL? Lets say it took me 2 man-month to write Quartz app, how much time will i need to rewrite it? (Please, just some subjective opinions, i'll try to summarize them somehow) Regarding the ease of migration to other platforms, when using OpenGL, is it really so? Or efforts when migrating Quartz app from iPhoneOS to Android will be not so much bigger, compared to OpenGL app migration? (Ease of migration is quite important criterion) Regarding OpenGL, should i go with OpenGL 1.1 or 2.0, concerning migration? (Android supports 2.0 through NDK, but dont know whether NDK's use will increase or decrease migration efforts)

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  • Overloading operator>> to a char buffer in C++ - can I tell the stream length?

    - by exscape
    I'm on a custom C++ crash course. I've known the basics for many years, but I'm currently trying to refresh my memory and learn more. To that end, as my second task (after writing a stack class based on linked lists), I'm writing my own string class. It's gone pretty smoothly until now; I want to overload operator that I can do stuff like cin my_string;. The problem is that I don't know how to read the istream properly (or perhaps the problem is that I don't know streams...). I tried a while (!stream.eof()) loop that .read()s 128 bytes at a time, but as one might expect, it stops only on EOF. I want it to read to a newline, like you get with cin to a std::string. My string class has an alloc(size_t new_size) function that (re)allocates memory, and an append(const char *) function that does that part, but I obviously need to know the amount of memory to allocate before I can write to the buffer. Any advice on how to implement this? I tried getting the istream length with seekg() and tellg(), to no avail (it returns -1), and as I said looping until EOF (doesn't stop reading at a newline) reading one chunk at a time.

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  • Volatile fields in C#

    - by Danny Chen
    From the specification 10.5.3 Volatile fields: The type of a volatile field must be one of the following: A reference-type. The type byte, sbyte, short, ushort, int, uint, char, float, bool, System.IntPtr, or System.UIntPtr. An enum-type having an enum base type of byte, sbyte, short, ushort, int, or uint. First I want to confirm my understanding is correct: I guess the above types can be volatile because they are stored as a 4-bytes unit in memory(for reference types because of its address), which guarantees the read/write operation is atomic. A double/long/etc type can't be volatile because they are not atomic reading/writing since they are more than 4 bytes in memory. Is my understanding correct? And the second, if the first guess is correct, why a user defined struct with only one int field in it(or something similar, 4 bytes is ok) can't be volatile? Theoretically it's atomic right? Or it's not allowed simply because that all user defined structs(which is possibly more than 4 bytes) are not allowed to volatile by design?

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  • Foosball result prediction

    - by Wolf
    In our office, we regularly enjoy some rounds of foosball / table football after work. I have put together a small java program that generates random 2vs2 lineups from the available players and stores the match results in a database afterwards. The current prediction of the outcome uses a simple average of all previous match results from the 4 involved players. This gives a very rough estimation, but I'd like to replace it with something more sophisticated, taking into account things like: players may be good playing as attacker but bad as defender (or vice versa) players do well against a specific opponent / bad against others some teams work well together, others don't skills change over time What would be the best algorithm to predict the game outcome as accurately as possible? Someone suggested using a neural network for this, which sounds quite interesting... but I do not have enough knowledge on the topic to say if that could work, and I also suspect it might take too many games to be reasonably trained. EDIT: Had to take a longer break from this due to some project deadlines. To make the question more specific: Given the following mysql table containing all matches played so far: table match_result match_id int pk match_start datetime duration int (match length in seconds) blue_defense int fk to table player blue_attack int fk to table player red_defense int fk to table player red_attack int fk to table player score_blue int score_red int How would you write a function predictResult(blueDef, blueAtk, redDef, redAtk) {...} to estimate the outcome as closely as possible, executing any sql, doing calculations or using external libraries?

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  • vector::erase with pointer member

    - by matt
    I am manipulating vectors of objects defined as follow: class Hyp{ public: int x; int y; double wFactor; double hFactor; char shapeNum; double* visibleShape; int xmin, xmax, ymin, ymax; Hyp(int xx, int yy, double ww, double hh, char s): x(xx), y(yy), wFactor(ww), hFactor(hh), shapeNum(s) {visibleShape=0;shapeNum=-1;}; //Copy constructor necessary for support of vector::push_back() with visibleShape Hyp(const Hyp &other) { x = other.x; y = other.y; wFactor = other.wFactor; hFactor = other.hFactor; shapeNum = other.shapeNum; xmin = other.xmin; xmax = other.xmax; ymin = other.ymin; ymax = other.ymax; int visShapeSize = (xmax-xmin+1)*(ymax-ymin+1); visibleShape = new double[visShapeSize]; for (int ind=0; ind<visShapeSize; ind++) { visibleShape[ind] = other.visibleShape[ind]; } }; ~Hyp(){delete[] visibleShape;}; }; When I create a Hyp object, allocate/write memory to visibleShape and add the object to a vector with vector::push_back, everything works as expected: the data pointed by visibleShape is copied using the copy-constructor. But when I use vector::erase to remove a Hyp from the vector, the other elements are moved correctly EXCEPT the pointer members visibleShape that are now pointing to wrong addresses! How to avoid this problem? Am I missing something?

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  • sql query - how to apply limit within group by

    - by Raj
    hey guys assuming i have a table named t1 with following fields: ROWID, CID, PID, Score, SortKey it has the following data: 1, C1, P1, 10, 1 2, C1, P2, 20, 2 3, C1, P3, 30, 3 4, C2, P4, 20, 3 5, C2, P5, 30, 2 6, C3, P6, 10, 1 7, C3, P7, 20, 2 what query do i write so that it applies group by on CID, but instead of returning me 1 single result per group, it returns me a max of 2 results per group. also where condition is score = 20 and i want the results ordered by CID and SortKey. If I had to run my query on above data, i would expect the following result: RESULTS FOR C1 - note: ROWID 1 is not considered as its score < 20 C1, P2, 20, 2 C1, P3, 30, 3 RESULTS FOR C2 - note: ROWID 5 appears before ROWID 4 as ROWID 5 has lesser value SortKey C2, P5, 30, 2 C2, P4, 20, 3 RESULTS FOR C3 - note: ROWID 6 does not appear as its score is less than 20 so only 1 record returned here C3, P7, 20, 2 IN SHORT, I WANT A LIMIT WITHIN A GROUP BY. I want the simplest solution and want to avoid temp tables. sub queries are fine. also note i am using sqlite for this

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  • mysql subselect alternative

    - by Arnold
    Hi, Lets say I am analyzing how high school sports records affect school attendance. So I have a table in which each row corresponds to a high school basketball game. Each game has an away team id and a home team id (FK to another "team table") and a home score and an away score and a date. I am writing a query that matches attendance with this seasons basketball games. My sample output will be (#_students_missed_class, day_of_game, home_team, away_team, home_team_wins_this_season, away_team_wins_this_season) I now want to add how each team did the previous season to my analysis. Well, I have their previous season stored in the game table but i should be able to accomplish that with a subselect. So in my main select statement I add the subselect: SELECT COUNT(*) FROM game_table WHERE game_table.date BETWEEN 'start of previous season' AND 'end of previous season' AND ( (game_table.home_team = team_table.id AND game_table.home_score > game_table.away_score) OR (game_table.away_team = team_table.id AND game_table.away_score > game_table.home_score)) In this case team-table.id refers to the id of the home_team so I now have all their wins calculated from the previous year. This method of calculation is neither time nor resource intensive. The Explain SQL shows that I have ALL in the Type field and I am not using a Key and the query times out. I'm not sure how I can accomplish a more efficient query with a subselect. It seems proposterously inefficient to have to write 4 of these queries (for home wins, home losses, away wins, away losses). I am sure this could be more lucid. I'll absolutely add color tomorrow if anyone has questions

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  • How to define custom path to Interop *.dll

    - by NoviceAndNovice
    Well, I have an ActiveX (*.ocx) component, and i use it in a managed C++/CLI project: write a managed wrapper around ActiveX component[ NET has a great Interop services : provides me genarated dll so i can easily use it in my managed code] The problem is that Visual Studio (2008) automatically copy the generated Interop *.dll to the directory where my *.exe file stay.But i want put all my genarated Interop *.dll to a folder ... Suppose My directory structure is so: D:\MyProject\Output\MyProject.exe //My mamanged exe D:\MyProject\Output\Interop.XXXLib.1.0.dll // *Interop .dll I want to put Interop.XXXLib.1.0.dll into new folder D:\MyProject\Output\Interops and use it from that directory...How Can i do it? Best Wishes PS: What I found so far was using using codeBase/ probing tags in my app.config file such as <?xml version="1.0"?> <configuration> <runtime> <assemblyBinding xmlns="urn:schemas-microsoft-com.asm.v1"> <probing privatePath="Interops" /> </assemblyBinding> </runtime> </configuration> But i did not work in C++/CLI

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  • Parsing every part of an HTTP header field-value

    - by brickner
    Hi all. I'm parsing HTTP data directly from packets (either TCP reconstructed or not, you can assume it is). I'm looking for the best way to parse HTTP as accurately as possible. The main issue here is the HTTP header. Looking at the basic RFC of HTTP/1.1, it seems that HTTP header parsing would be complex. The RFC describes very complex regular expressions for different parts of the header. Should I write these regular expressions to parse the different parts of the HTTP header? The basic parsing I've written so far for HTTP header is for the generic HTTP header: message-header = field-name ":" [ field-value ] And I've included replacing inner LWS with SP and repeating headers with the same field-name with comma separated values as described in section 4.2. However, looking at section 14.9 for example would show that in order to parse the different parts of the field-value I need a much more complex parsing scheme. How do you suggest I should handle the complex parts of HTTP parsing (specifically the field-value) assuming I want to give the parser users the full capabilities of HTTP and to parse every part of HTTP? Design suggestions for this would also be appreciated. Thanks.

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  • Practical refactoring using unit tests

    - by awhite
    Having just read the first four chapters of Refactoring: Improving the Design of Existing Code, I embarked on my first refactoring and almost immediately came to a roadblock. It stems from the requirement that before you begin refactoring, you should put unit tests around the legacy code. That allows you to be sure your refactoring didn't change what the original code did (only how it did it). So my first question is this: how do I unit-test a method in legacy code? How can I put a unit test around a 500 line (if I'm lucky) method that doesn't do just one task? It seems to me that I would have to refactor my legacy code just to make it unit-testable. Does anyone have any experience refactoring using unit tests? And, if so, do you have any practical examples you can share with me? My second question is somewhat hard to explain. Here's an example: I want to refactor a legacy method that populates an object from a database record. Wouldn't I have to write a unit test that compares an object retrieved using the old method, with an object retrieved using my refactored method? Otherwise, how would I know that my refactored method produces the same results as the old method? If that is true, then how long do I leave the old deprecated method in the source code? Do I just whack it after I test a few different records? Or, do I need to keep it around for a while in case I encounter a bug in my refactored code? Lastly, since a couple people have asked...the legacy code was originally written in VB6 and then ported to VB.NET with minimal architecture changes.

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  • Can I use a specific model from within a behavior in CakePHP?

    - by Paul Willy
    I'm trying to write a behavior that will give my models access to a simple workflow engine I've devised. The workflow engine itself works as a CakePHP model, with workflow data stored in the database just as any other model data is stored. Basically what I want to do is have the behavior use the workflow model whenever an action is called on the base model. For example, if the edit() action is executed for Posts, then the Post (with the behavior attached) will trigger the workflow behavior with its own model name, action, and id as arguments (e.g. [Post, edit, 1]). Then the behavior will invoke the functionality of the Workflow model, which has a record for what to do when edit is run on Posts (e.g. send e-mail to users who are subscribed to that post) and will carry that out. My question is, what is the proper way to invoke model/controller methods from within the behavior? The model to be used from within the behavior will always be Workflow, but the behavior should be usable from basically any model (aside from Workflow itself). I know I could run SQL queries directly from the behavior, but of course this is not the Cake way :-) Or, am I going about this in the wrong way? I want to store a certain amount of logic in the database so that it is easily configurable by different users, and not have endless configuration checks within the model/controller logic itself so that workflow steps can be easily added/changed/removed in the future.

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