———————————–
Undefined symbols:
"_cvLoadImage", referenced from:
_main in main.o
"_cvNamedWindow", referenced from:
_main in main.o
"_cvReleaseImage", referenced from:
_main in main.o
"_cvShowImage", referenced from:
_main in main.o
"_cvDestroyWindow", referenced from:
_main in main.o
"_cvWaitKey", referenced from:
_main in main.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
———————————–

Does anyone know what these mean? 1. Max.

Thanks, that solved it!

^w^

Read the tutorial on functions at the following URL:

http://www.cplusplus.com/doc/tutorial/functions

If you read the tutorial, you'll see that putting the code for your Convert() function before main() should eliminate the compiler error.

I've been using SAMS Teach Yourself C++ Fifth Edition by Jesse Liberty and Bradley Jones to learn C++, but I'm having some problems with function declarations and definitions on Xcode. I follow the code exactly, but I get errors. I tried multiple examples from the book, and all of the programs regarding functions produce errors. Here's an example:

// Listing 5.2
// Demo of the Use of Local Variables and Parameters

#include iostream

float Convert(float)
int main() // error: expected initializer before "int"
{
using namespace std;

float TempFer;
float TempCel;

cout << "\nPlease enter the temperature in Fahrenheit: ";
cin >> TempFer;
TempCel = Convert(TempFer);
cout << "\nHere is the temperature in Celsius: ";
cout << TempCel << endl;
return 0;
}

float Convert(TempFer) // error: 'TempFer' was not declared in this scope
{ // error: expected ',' or ';' before '{' token
float TempCel;
TempCel = ((TempFer – 32) * 5) / 9;
return TempCel;
}

For the first error, when I take out "float Convert(float)", that error disappears. So does "#include iostream" have to immediately precede "int main()"?

Thank you very much!

^w^

PS> My tags are taken out because HTML cannot accept it.

If you're using Xcode 3, choose Run > Console to enter input and see the output from the program.

X11 is the windowing system Unix operating systems use. Mac OS X has an X11 application that lets you run X11 apps on your Mac. X11 should be in your Applications folder under Utilities. If it's not there, you'll have to install it from your Mac OS X DVD.

You would use OpenGL to write graphics programs on a Mac. You would use an image editing program like Photoshop or GIMP to create the graphic images.

Only problem(s)?

When I try to go to the "run" or "go" section of Xcode (or try to compile for that matter), it opens a window that says "Stop Executable". The program still works if I open it through terminal (which I believe is the standard command line interface for mac.

For curiosity sake, what is X11 and how do you create graphics for c++ programs on a mac? (My cousin created a small single player game with graphics).

Thank you for your time.

Yes, you can use C++ for the non-GUI portions of your program and use Tkinter or Cocoa for the GUI.

The decision of which GUI framework to use depends on the program and who is going to use the program. If your program is intended for the mass market of general Mac users, going with Cocoa would be a good choice. You can write Cocoa applications with Python using PyObjC. Xcode 3 has project templates for Cocoa Python programs. If the program has a more specialized audience, you would be better off sticking with Tkinter.

I’m not familiar with Tkinter so I don’t know how easy it is to integrate with Xcode. I know Mac OS X ships with the Python, Tcl, and Tk frameworks. If there’s a Tkinter framework available for Mac OS X, using Xcode will be easy. All you would have to do is add the framework. If there isn’t a framework available, more work would be required.

If you need a more detailed answer, send me an email. There’s a link to my website in the sidebar on the right side of this blog.

Thanks again,

Gabriel