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  • algorithm to combine data for linear fit?

    - by BoldlyBold
    I'm not sure if this is the best place to ask this, but you guys have been helpful with plenty of my CS homework in the past so I figure I'll give it a shot. I'm looking for an algorithm to blindly combine several dependent variables into an index that produces the best linear fit with an external variable. Basically, it would combine the dependent variables using different mathematical operators, include or not include each one, etc. until an index is developed that best correlates with my external variable. Has anyone seen/heard of something like this before? Even if you could point me in the right direction or to the right place to ask, I would appreciate it. Thanks.

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  • Pass temporary object to function that takes pointer

    - by Happy Mittal
    I tried following code : #include<iostream> #include<string> using namespace std; string f1(string s) { return s="f1 called"; } void f2(string *s) { cout<<*s<<endl; } int main() { string str; f2(&f1(str)); } But this code doesn't compile. What I think is : f1 returns by value so it creates temporary, of which I am taking address and passing to f2. Now Please explain me where I am thinking wrong?

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  • Saving a 'Date' using DataMapper on AppEngine+JRuby

    - by Ryan Montgomery
    I have a a model as follows: class Total include DataMapper::Resource property :id, Serial property :amount, Float, :default => 0.00 property :day, Date belongs_to :calendar end I am trying to select a specific Total from the data-store. class Calendar include DataMapper::Resource property :id, Serial property :name, String has n, :totals def get_total_for(date) return Total.first(:day => date, :calendar => self) end end When I call get_total_for(DateTime.now) I receive the following error on the call to the data-store. java.lang.IllegalArgumentException: day: org.jruby.RubyObject is not a supported property type. Is Date not allowed for usage in AppEngine? Is this a DataMapper issue? I have tried changing the name of the :day property to something else (hoping it was just a name conflict) but it doesn't seem to matter. Thanks for any help you can provide.

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  • jquery: show data after change event

    - by klox
    i have this code: <script> $("#mod").change(function() { var matches=str.match(/(EE|[EJU]).*(D)/i); $.ajax({ type="post", url="process.php", data="matches", cache=false, async=false, success= function(res){ $('#rslt').replaceWith("<div id='value'><h6>Tuner range is" + res + " .</h6></div>"); return this; } }); return false; }); </script> i want this code can show the result normally..where is my fault?

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  • SDL+OpenGL app: blank screen

    - by Lococo
    I spent the last three days trying to create a small app using SDL + OpenGL. The app itself runs fine -- except it never outputs any graphics; just a black screen. I've condensed it down to a minimal C file, and I'm hoping someone can give me some guidance. I'm running out of ideas. I'm using Windows Vista, MinGW & MSYS. Thanks in advance for any advice! #include <SDL/SDL.h> #include <SDL_opengl.h> size_t sx=600, sy=600, bpp=32; void render(void) { glEnable(GL_DEPTH_TEST); // enable depth testing glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // clear to black glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // clear color/depth buffer glLoadIdentity(); // reset modelview matrix glColor3b(255, 0, 0); // red glLineWidth(3.0); // line width=3 glRecti(10, 10, sx-10, sy-10); // draw rectangle glFlush(); SDL_GL_SwapBuffers(); } int input(void) { SDL_Event event; while (SDL_PollEvent(&event)) if (event.type == SDL_QUIT || (event.type == SDL_KEYUP && event.key.keysym.sym == SDLK_ESCAPE)) return 0; return 1; } int main(int argc, char *argv[]) { SDL_Surface* surf; if (SDL_Init(SDL_INIT_EVERYTHING) != 0) return 0; if (!(surf = SDL_SetVideoMode(sx, sy, bpp, SDL_HWSURFACE|SDL_DOUBLEBUF))) return 0; glViewport(0, 0, sx, sy); // reset the viewport to new dimensions glMatrixMode(GL_PROJECTION); // set projection matrix to be current glLoadIdentity(); // reset projection matrix glOrtho(0, sx, sy, 0, -1.0, 1.0); // create ortho view glMatrixMode(GL_MODELVIEW); // set modelview matrix glLoadIdentity(); // reset modelview matrix for (;;) { if (!input()) break; render(); SDL_Delay(10); } SDL_FreeSurface(surf); SDL_Quit(); exit(0); } UPDATE: I have a version that works, but it changes orthographic to perspective. I'm not sure why this works and the other doesn't, but for future reference, here's a version that works: #include <SDL/SDL.h> #include <SDL_opengl.h> size_t sx=600, sy=600, bpp=32; void render(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); // set location in front of camera glTranslated(0, 0, -10); glBegin(GL_QUADS); // draw a square glColor3d(1, 0, 0); glVertex3d(-2, 2, 0); glVertex3d( 2, 2, 0); glVertex3d( 2, -2, 0); glVertex3d(-2, -2, 0); glEnd(); glFlush(); SDL_GL_SwapBuffers(); } int input(void) { SDL_Event event; while (SDL_PollEvent(&event)) if (event.type == SDL_QUIT || (event.type == SDL_KEYUP && event.key.keysym.sym == SDLK_ESCAPE)) return 0; return 1; } int main(int argc, char *argv[]) { SDL_Surface *surf; if (SDL_Init(SDL_INIT_EVERYTHING) != 0) return 0; if (!(surf = SDL_SetVideoMode(sx, sy, bpp, SDL_OPENGL))) return 0; glViewport(0, 0, sx, sy); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.0, (float)sx / (float)sy, 1.0, 100.0); glMatrixMode(GL_MODELVIEW); glClearColor(0, 0, 0, 1); glClearDepth(1.0); glEnable(GL_DEPTH_TEST); for (;;) { if (!input()) break; render(); SDL_Delay(10); } SDL_FreeSurface(surf); SDL_Quit(); return 0; }

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  • C static variables and intialization

    - by yCalleecharan
    Hi, If I have a global static variable x like in this code #include <stdio.h> #include <stdio.h> static int x; int main(void) { DO SOMETHING WITH x HERE x++; } What will be difference if I opted to initialize x to a value first say as in static int x = 0; before entering "main"? In my first case where I didn't assign a value to x, does the compiler implicitly know that x is to be set to zero as it's a static variable? I heard that we can do this with static variables. Thanks a lot...

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  • WinMain not called before main (C/C++ Program Entry Point Issue)

    - by BT
    I was under the impression that this code #include <windows.h> #include <stdio.h> int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { printf("WinMain\n"); return 0; } int main() { printf("main\n"); return 0; } would output WinMain, but of course nothing ever works how you expects. Anyways, could somebody please tell me how to get this program to run WinMain first (I do have a reason for using both). I'm running windows 7 with mingw if that helps anything.

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  • how can we generate the bit greater than 60000?

    - by thinthinyu
    we can now generate about 50000bits. my code cannot generate more than 60000 bit..please help me............m_B is member variable and type is CString. // LFSR_ECDlg.cpp : implementation file // #include "stdafx.h" #include "myecc.h" #include "LFSR_ECDlg.h" #include "MyClass.h" #ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif extern MyClass mycrv; ///////////////////////////////////////////////////////////////////////////// // LFSR_ECDlg dialog LFSR_ECDlg::LFSR_ECDlg(CWnd* pParent /*=NULL*/) : CDialog(LFSR_ECDlg::IDD, pParent) { //{{AFX_DATA_INIT(LFSR_ECDlg) m_C1 = 0; m_C2 = 0; m_B = _T(""); m_p = _T(""); m_Qty = 0; m_time = _T(""); //}}AFX_DATA_INIT } void LFSR_ECDlg::DoDataExchange(CDataExchange* pDX) { CDialog::DoDataExchange(pDX); //{{AFX_DATA_MAP(LFSR_ECDlg) DDX_Text(pDX, IDC_C1, m_C1); DDX_Text(pDX, IDC_C2, m_C2); DDX_Text(pDX, IDC_Sequence, m_B); DDX_Text(pDX, IDC_Sequence2, m_p); DDX_Text(pDX, IDC_QTY, m_Qty); DDV_MinMaxLong(pDX, m_Qty, 0, 2147483647); DDX_Text(pDX, IDC_time, m_time); //}}AFX_DATA_MAP } BEGIN_MESSAGE_MAP(LFSR_ECDlg, CDialog) //{{AFX_MSG_MAP(LFSR_ECDlg) ON_WM_SETCURSOR() ON_EN_CHANGE(IDC_Sequence, OnGeneratorLFSR) ON_MESSAGE(WM_MYPAINTMESSAGE,PaintMyCaption)//by ttyu ON_BN_CLICKED(IDC_save, Onsave) //}}AFX_MSG_MAP END_MESSAGE_MAP() ///////////////////////////////////////////////////////////////////////////// // LFSR_ECDlg message handlers bool LFSR_ECDlg::CheckDataEntry() { //if((m_Px>=mycrv.p)|(m_Py>=mycrv.p)) {AfxMessageBox("Seed [P] is invalid!");return false;}//by ttyu if((m_C1<=0) | (m_C1>mycrv.n)) {AfxMessageBox("Constant c1 is not valid!");return false;} if((m_C2<=0 )| (m_C2>mycrv.n)) {AfxMessageBox("Constant c2 is not valid!");return false;} return true; } void LFSR_ECDlg::OnOK() { UpdateData(true); static int stime,etime,dtime; CString txt; m_time=""; CTime t(CTime::GetCurrentTime()); CString txt1; txt1=""; //ms = t.GetDay(); // TODO: Add extra validation here stime=t.GetTime(); txt1.Format("%d",stime); AfxMessageBox (txt1); txt=""; if (CheckDataEntry()) OnGeneratorLFSR(); etime=t.GetTime(); CString txt2; txt2=""; txt2.Format("%d",etime); AfxMessageBox (txt2); dtime=etime-stime; txt.Format("%f",dtime); m_time+=txt; // UpdateData(false); //rtime.Format("%s, %s %d, %d.",day,month,dd,yy); //CDialog::OnOK(); } void LFSR_ECDlg::OnCancel() { // TODO: Add extra cleanup here CDialog::OnCancel(); } void LFSR_ECDlg::OnGeneratorLFSR() { // TODO: If this is a RICHEDIT control, the control will not // send this notification unless you override the CDialog::OnInitDialog() // function and call CRichEditCtrl().SetEventMask() // with the ENM_CHANGE flag ORed into the mask. // TODO: Add your control notification handler code here point P0,P1,P2; P0 = mycrv.G; P1 = mycrv.MulPoint(P0,2); int C1=m_C1, C2=m_C2, n=m_Qty, k=0; int q= (mycrv.p-1) / 2; m_p = ""; m_B = ""; CString txt; for(int i=0;i<n;i++) { txt=""; if(P0==mycrv.O) txt.Format("O"); else txt.Format("(%d, %d)",P0.x,P0.y); m_p +=txt; m_p += 13; m_p += 10; if((P0.y >= 0)&&(P0.y <= q)) m_B += "0"; else if(P0 == mycrv.O) m_B += "0"; else m_B += "1"; //m_B += 13;//by ttyu // m_B += 10;//by ttyu P2 = mycrv.AddPoints(mycrv.MulPoint(P1,C2), mycrv.MulPoint(P0,C1)); P0 = P1; P1 = P2; } } BOOL LFSR_ECDlg::OnInitDialog() { CDialog::OnInitDialog(); // TODO: Add extra initialization here //code for dlg bar CString str="LFSR_EC"; m_cap.SetCaption (str); m_cap.Install (this,WM_MYPAINTMESSAGE); ////////////////////////////// return TRUE; // return TRUE unless you set the focus to a control // EXCEPTION: OCX Property Pages should return FALSE } LRESULT LFSR_ECDlg::PaintMyCaption(WPARAM wp, LPARAM lp) { m_cap.PaintCaption(wp,lp); return 0; } BOOL LFSR_ECDlg::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message) { // TODO: Add your message handler code here and/or call default return CDialog::OnSetCursor(pWnd, nHitTest, message); } void LFSR_ECDlg::Onsave() { this->UpdateData(); CFile bitstream; char strFilter[] = { "Stream Records (*.mpl)|*.mpl| (*.pis)|*.pis|All Files (*.*)|*.*||" }; CFileDialog FileDlg(FALSE, ".mpl", NULL, 0, strFilter); //insertion//by TTT CFile cf_object; if( FileDlg.DoModal() == IDOK ){ cf_object.Open( FileDlg.GetFileName(), CFile::modeCreate|CFile::modeWrite); //char szText[100]; //strcpy(szText, "File Write Test"); CString txt; txt=""; txt.Format("%s",m_B);//by ANO AfxMessageBox (txt);//by ANO int mB_size=m_B.GetLength(); cf_object.Write (m_B,mB_size); //insertion end /* if( FileDlg.DoModal() == IDOK ) { if( bitstream.Open(FileDlg.GetFileName(), CFile::modeCreate | CFile::modeWrite) == FALSE ) return; CArchive ar(&bitstream, CArchive::store); CString txt; txt=""; txt.Format("%s",m_B);//by ANO AfxMessageBox (txt);//by ANO //txt=m_B;//by ANO ar <<txt;//by ANO ar.Close(); } else return; bitstream.Close(); */ // TODO: Add your control notification handler code here } }

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  • Why this C program outputs a negative number?

    - by JMSA
    I have assigned the complement value in an unsigned variable. Then why this C program outputs a negative number? #include<stdio.h> #include<conio.h> int main() { unsigned int Value = 4; /* 4 = 0000 0000 0000 0100 */ unsigned int result = 0; result = ~ Value; /* -5 = 1111 1111 1111 1011 */ printf("result = %d", result); /* -5 */ getch(); return 0; }

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  • Limit child rows in Entity Framework Query

    - by Jim
    Hi, If I have a parent and child modelled relationship. How to I select the parent, and some of the child rows. I cannot seem to do it, and load the parent object. var query = ( from parent in Parents.Include("Children") from child in parent.Children where child.Date == parent.Children.Max(x => x.Date) select parent); the problem is that the parent is returned multiple times, not the parent with the children loaded. Is there any way to populate each of the parents, and include the child rows, but only the ones needed. If I try and navigate again, I get all the children, not just the ones with the latest date. Thanks

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  • How to efficiently implement a blocking call with Rails, while letting the client wait for the reply

    - by Kyle Heironimus
    We have a web service written in Rails. The API is published and we cannot change it. Our app communicates with a remote web service that sometimes hangs or takes several seconds to reply. Client -> Our Web Service -> Remote Web Service Currently, if the remote web service hangs for 5 seconds, one of our rails processes on our web service also hangs with it, which is what we need to avoid. I've seen things such as mod-x-sendfile, modporter, and delayed jobs, but the best I can tell, they all assume the client is not waiting for an answer. Since the API is already established, we cannot tell the client "I'm attempting to do what you want, check back later for the answer." The best option we have come up with so far is to add a second, non-rails web server running eventmachine to process these particular calls. Is there a better way?

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  • C++ - defining static const integer members in class definition

    - by HighCommander4
    My understanding is that C++ allows static const members to be defined inside a class so long as it's an integer type. Why, then, does the following code give me a linker error? #include <algorithm> #include <iostream> class test { public: static const int N = 10; }; int main() { std::cout << test::N << "\n"; std::min(9, test::N); } The error I get is: test.cpp:(.text+0x130): undefined reference to `test::N' collect2: ld returned 1 exit status Interestingly, if I comment out the call to std::min, the code compiles and links just fine (even though test::N is also referenced on the previous line). Any idea as to what's going on? My compiler is gcc 4.4 on Linux.

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  • need to run php script when form is submitted

    - by Brad
    I have a form that needs to run a php script once the submit button is clicked, it needs to be ajax. <form method="post" action="index.php" id="entryform" name="entryform"> <input type="submit" name="submit" value="Submit" onclick="JavaScript:xmlhttpPost('/web/ee_web/include/email-notification.php', 'entryform')" /> </form> In this situation, using if(form posted) { get results and run script } is not an option, I need to run the script externally, that is why I need it to execute the email-notification.php at onclick When I point my web browser to domain.com/include/email-notification.php - it runs perfectly. Any help is appreciated.

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  • Why is this c++ string concatenation missing a space?

    - by danutenshu
    I am working with c++ strings, and am a beginner at programming. I am expecting: 99 Red Balloons But I am receiving: 99 RedBalloons Why is that? #include <string> #include <iostream> using namespace std; int main() { string text = "9"; string term( "9 "); string info = "Toys"; string color; char hue[4] = {'R','e','d','\0'}; color = hue; info = "Balloons"; text += (term + color + info); cout << endl << text << endl; return 0; }

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  • C++: Simplifying my program to convert numbers to from one base to another.

    - by Spin City
    Hello, I'm taking a beginner C++ course. I received an assignment telling me to write a program that converts an arbitrary number from any base between binary and hex to another base between binary and hex. I was asked to use separate functions to convert to and from base 10. It was to help us get used to using arrays. (We already covered passing by reference previously in class.) I already turned this in, but I'm pretty sure this wasn't how I was meant to do it: #include <iostream> #include <conio.h> #include <cstring> #include <cmath> using std::cout; using std::cin; using std::endl; int to_dec(char value[], int starting_base); char* from_dec(int value, int ending_base); int main() { char value[30]; int starting_base; int ending_base; cout << "This program converts from one base to another, so long as the bases are" << endl << "between 2 and 16." << endl << endl; input_numbers: cout << "Enter the number, then starting base, then ending base:" << endl; cin >> value >> starting_base >> ending_base; if (starting_base < 2 || starting_base > 16 || ending_base < 2 || ending_base > 16) { cout << "Invalid base(s). "; goto input_numbers; } for (int i=0; value[i]; i++) value[i] = toupper(value[i]); cout << "Base " << ending_base << ": " << from_dec(to_dec(value, starting_base), ending_base) << endl << "Press any key to exit."; getch(); return 0; } int to_dec(char value[], int starting_base) { char hex[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; long int return_value = 0; unsigned short int digit = 0; for (short int pos = strlen(value)-1; pos > -1; pos--) { for (int i=0; i<starting_base; i++) { if (hex[i] == value[pos]) { return_value+=i*pow((float)starting_base, digit++); break; } } } return return_value; } char* from_dec(int value, int ending_base) { char hex[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; char *return_value = (char *)malloc(30); unsigned short int digit = (int)ceil(log10((double)(value+1))/log10((double)ending_base)); return_value[digit] = 0; for (; value != 0; value/=ending_base) return_value[--digit] = hex[value%ending_base]; return return_value; } I'm pretty sure this is more advanced than it was meant to be. How do you think I was supposed to do it? I'm essentially looking for two kinds of answers: Examples of what a simple solution like the one my teacher probably expected would be. Suggestions on how to improve the code.

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  • How to create a GtkImage from a Cairo context?

    - by Zurbo82
    I got a paint function that works using a Cairo context and the end result should be a GtkImage (without intermediate image creation). I tried to use the gdk_cairo_create function but this code: ... GdkPixbuf *pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 22, 22); GtkWidget *image = gtk_image_new_from_pixbuf (pixbuf); GdkDrawable *drawable = image->window; cairo_t *ctx = gdk_cairo_create (drawable); my_cairo_paint_function (ctx); ... fails with: Gdk-CRITICAL **: IA__gdk_cairo_create: assertion `GDK_IS_DRAWABLE (drawable)' failed Same with a simple: #include <gtk/gtk.h> #include <cairo.h> int main (int argc, char *argv[]) { gtk_init(&argc, &argv); cairo_t *ctx = gdk_cairo_create (gtk_widget_get_window (gtk_image_new_from_file ("foobar.png"))); gtk_main(); return 0; } I don't understand why this fails. Any help is appreciated!

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  • visual studio 2010 add reference version missing

    - by Noel
    In VS2008 when I add a reference to a dll e.g log4Net I get the following in csproj <Reference Include="log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=1b44e1d426115821, processorArchitecture=MSIL"> <SpecificVersion>False</SpecificVersion> <HintPath>..\..\lib\log4net\log4net.dll</HintPath> </Reference> In VS2010 when I add a reference to a dll for the first time e.g log4Net I get the following in csproj (i.e no version number etc) <Reference Include="log4net"> <HintPath>..\..\lib\log4net\log4net.dll</HintPath> </Reference> If I remove reference and add a second time the same details as in VS2008 is there (Version etc) Anyone know why version number etc not present the first time I add a reference and why it is present on secound time reference added?

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  • How Iostream file is located in computer by c++ code during execution

    - by user3702024
    i want to know that in a c++ code during execution how iostream file is founded. we write #include in c++ program and i know about #include which is a preprocessor directive to load files and is a file name but i don't know that how that file is located. i have some questions in my mind... Is Standard library present in compiler which we are using? Is that file is present in standard library or in our computer? Can we give directory path to locate the file through c++ code if yes then how?

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  • Jquery select add values from json

    - by brabertaser1992
    I have such json: [ { "MOD_AXL": 0, "MOD_CDS_ID": 110000168, "MOD_CV": 0, "MOD_CV_CTM": null, "MOD_ID": 168, "MOD_MFA_ID": 514, "MOD_PC": 1, "MOD_PCON_END": 199007, "MOD_PCON_START": 196303, "MOD_PC_CTM": null, "Name": "2 CV"}, { "MOD_AXL": 0, "MOD_CDS_ID": 110004500, "MOD_CV": 0, "MOD_CV_CTM": null, "MOD_ID": 4500, "MOD_MFA_ID": 514, "MOD_PC": 1, "MOD_PCON_END": 198810, "MOD_PCON_START": 197808, "MOD_PC_CTM": null, "Name": "ACADIANE"}, { "MOD_AXL": 0, "MOD_CDS_ID": 110001660, "MOD_CV": 0, "MOD_CV_CTM": null, "MOD_ID": 1660, "MOD_MFA_ID": 514, "MOD_PC": 1, "MOD_PCON_END": 197712, "MOD_PCON_START": 196301, "MOD_PC_CTM": null, "Name": "AMI"} // etc..etc.. ]? But how to set as select value MOD_ID, and as text of select option: Name? I have this data in text: $(".man-select").change(function(){ var mfa_id = $(".man-select").val(); console.log(mfa_id); $.ajax({ url: "/get_models_for_mfa/mfa_id="+mfa_id+".json", type: "GET", data: {}, success: function(text) //here is object { console.log("getted"); $('.mod-select') .append($("<option></option>") .attr("value",text) .text(text)); }, error: function(){ //alert('?????? javascript'); }, dataType : "html" }); });

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  • syntax error, unexpected ',', expecting ')' RoR

    - by McDoku
    I am trying to get a collection select from an another model and I keep getting the above error. Looked everywhere, got rails casts but nothing makes sense. _form.rb <%= f.label :city %><br /> <%= f.collection_select (:share ,:city_id, City.all , :id, :name ) %> It highlights 'form' on the error report <h1>New share</h1> <%= render 'form' %> <%= link_to 'Back', shares_path %> Here are my models... class Share include Mongoid::Document field :name, type: String field :type, type: String field :summary, type: String field :description, type: String field :city, type: String embedded_in :city has_many :category end class City include Mongoid::Document embedded_in :share field :name, type: String field :country, type: String attr_accessible :name, :city_id, :id end Searched everywhere and I cannot figure it out. It must be something silly.

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  • An exception to the "only one implementation" rule ?

    - by ereOn
    While I was reading the accepted answer of this question, I had the following question: Typically, methods are defined in header files (.hpp or whatever), and implementation in source files (.cpp or whatever). One of the main reasons it is bad practice to ever include a "source file" (#include <source_file.cpp>) is that its methods implementation would then be duplicated, resulting in linking errors. When one writes: #ifndef BRITNEYSPEARS_HPP #define BRITNEYSPEARS_HPP class BritneySpears { public: BritneySpears() {}; // Here the constructor has implementation. }; #endif /* BRITNEYSPEARS_HPP */ He is giving the implementation of the constructor (here an "empty" implementation, but still). But why then including this header file multiple times (aka. on different source files) will not generate a "duplicate definition" error at link time ?

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  • API verbs for an interruptible operation

    - by 280Z28
    I have a long running task as part of my application. The task can be started, paused, resumed, and cancelled. I'm trying to find the best interface for these operations. Two seem clear: Pause and Cancel. This leaves the start and resume operations. I could include both Start and Resume. This has the downside of either requiring the API consumer to check the state before starting/resuming the operation to call the right method, or making the methods aliases of each other. I'm thinking I should include either Start or Resume, but I don't know which one is the most appropriate. Does anyone have any examples in the .NET Framework of such behavior? I prefer to follow established patterns whenever they are available.

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  • c++/cli pass (managed) delegate to unmanaged code

    - by Ron Klein
    How do I pass a function pointer from managed C++ (C++/CLI) to an unmanaged method? I read a few articles, like this one from MSDN, but it describes two different assemblies, while I want only one. Here is my code: 1) Header (MyInterop.ManagedCppLib.h): #pragma once using namespace System; namespace MyInterop { namespace ManagedCppLib { public ref class MyManagedClass { public: void DoSomething(); }; }} 2) CPP Code (MyInterop.ManagedCppLib.cpp) #include "stdafx.h" #include "MyInterop.ManagedCppLib.h" #pragma unmanaged void UnmanagedMethod(int a, int b, void (*sum)(const int)) { int result = a + b; sum(result); } #pragma managed void MyInterop::ManagedCppLib::MyManagedClass::DoSomething() { System::Console::WriteLine("hello from managed C++"); UnmanagedMethod(3, 7, /* ANY IDEA??? */); } I tried creating my managed delegate and then I tried to use Marshal::GetFunctionPointerForDelegate method, but I couldn't compile.

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