Headers order below
#include <winsock2.h>
#include <ws2tcpip.h>
#include <windows.h>
All code was written and debugged in VS2019, and compiles there fine. But after migration appears classic problem of misordering winsockets headers.
As that
error C2011: 'sockaddr' : 'struct' type redefinition
Anybody any suggestions, what is the cause ?
in centos eclipse. Got a bug says "function runtime_error could not be resolved". I added -std=c++11 or -std=c++0x in the settings and rebuild the index. (see Multiple "could not be resolved" problems using Eclipse with minGW )
it still shows a bug in the CDT.
But in my makefile I added -std=c++0x it got compiled with no error.
the line has the bug is
throw runtime_error("error msg");
I included those header files
#include <cerrno>
#include <system_error>
using namespace std;
void main()
{
throw runtime_error("blabla");
}
First I wanted to compile MatConvNet library for using in windows form this tutorial
(Compiling MatConvNet on Windows)
but I couldn't. Then I think it is better to compile a very simple file and after that going to compile the library.
I have Matlab R2013a 64 bit and Visual Studio 2010 64 bit.
my program Test.cpp
#include "mex.h"
void mexFunction(int nlhs, mxArray *plhs[],int nrhs, const mxArray *prhs[])
{
printf("Hello! :)\n");
}
I can compile Test.cpp in matlab with mex Test.cpp
And when I type test output is Hello! :)
I also can set the correct configuration according to tutorials below and compile it without errors.
1) http://coachk.cs.ucf.edu/GPGPU/Compiling_a_MEX_file_with_Visual_Studio2.htm
2) http://www.orangeowlsolutions.com/archives/490
But when I run it in Matlab, nothing happen. There is no output and Matlab doesn't give me any error.
What is the problem?
Notice that:
in (1) second step is adding "mexversion.rc" from "matlab\extern\include" to the project But this file dose not exist in my computer so I couldn't do it.
In Visual Studio I needed to add tow headers in below for compiling the program.
include "stdafx.h"
include "maxrix.h"
so the Test.cpp in Visual Studio is:
#include "mex.h"
#include "stdafx.h"
#include "matrix.h"
void mexFunction(int nlhs, mxArray *plhs[],int nrhs, const mxArray *prhs[])
{
printf("Hello! :)\n");
}
Pre-compiled header shenanigans
A problem with the Visual Studio version of the code is the pre-compiled header file stdafx.h causing the compiler to ignore any code above it (the mex.h include):
#include "mex.h"
#include "stdafx.h" // ANYTHING above here is IGNORED!
#include "matrix.h"
Move the stdafx.h include to the top or turn off PCH in projects settings and remove the include.
printf vs. mexPrintf
Before getting into MEX project setup, note that printf points to mexPrintf courtesy of mex.h:
#define printf mexPrintf
So, using printf is not an issue, but probably not good practice. The problem comes if you redefine printf after including mex.h or fail to get this define on account of the PCH header.
Regarding MEX in Visual Studio
I posted a more formal guide to setting up a Visual Studio projects for building MEX files as an answer to the more commonly-reference question on this topic, and I would also suggest here to use Visual Studio property sheets to get your project set up to build a MEX file. The details are in the referenced post, but you just need to:
Set the MATLAB_ROOT environment variable.
Create a new DLL project.
Under Property Manager (from View menu), right click on each project's build configuration and "Add Existing Property Sheet...", choosing the MATLABx64.props file from this GitHub repo.
printf only works in native C. You need to use mexPrintf. Therefore, your code should be this:
#include "mex.h"
void mexFunction(int nlhs, mxArray *plhs[],int nrhs, const mxArray *prhs[])
{
mexPrintf("Hello! :)\n");
}
In general, printing to standard output in a MEX script doesn't appear in the MATLAB command prompt. If you want to display messages in MATLAB, you need to use mexPrintf instead of printf.
To be explicit, if you consult the mexPrintf documentation, a caveat can be seen towards the end:
In a C MEX-file, you must call mexPrintf instead of printf to display a string.
BTW, I recommend this awesome MEX tutorial here: http://classes.soe.ucsc.edu/ee264/Fall11/cmex.pdf. This is the tutorial that I used to get started with programming MEX wrappers in MATLAB. You'll also see that the first example is of the same "Hello World" caliber that you are trying to get running :)
Good luck!
How To Compile a C/CPP File and Create mex File for Using in Matlab
I found the solution by #rayryeng help and (How to build mex file directly in Visual Studio?) #jorre's post.
This is tested with Matlab R2013a 64 bit and Visual Studio 2010 64 bit.
Test.cpp
#include "mex.h"
void mexFunction(int nlhs, mxArray *plhs[],int nrhs, const mxArray *prhs[])
{
mexPrintf("Hello World123! :)\n");
}
1.Create a new project in VS -> Visual C++ -> General -> Empty Project.
The name of your Project will be the name of mex file.
You can change it later.
2.Change the Debug to Release.
Right click on the project -> Properties -> Configuration properties -> General
Set Target Extension to .mexw64
Set Configuration Type to Dynamic Library (.dll)
Configureation poperties -> VC++ Directories:
5.Add $(MATLAB_ROOT)\extern\include; to Include Directories
Configuration properties -> Linker -> General:
Add $(MATLAB_ROOT)\extern\lib\win64\microsoft; to Additional Library Directories
Configuration properties -> Linker -> Input:
Add these things to Additional Dependencies
libmx.lib
libmex.lib
libmat.lib
Configuration properties -> Linker -> Command Line:
Add /export:mexFunction to Additional Options
Now you must set you platform to x64 otherwise you'll get error like"Error 1 error LNK2001: unresolved external symbol _mexPrintf".
9.Configuration Properties -> Configuration Manager -> Active Solution Platform -> New -> x64 -> Copy Settings From Win32
Now you can compile your file and get mex file.
If you see these tutorials there are other things thar are not needed and may cause problems.
(http://coachk.cs.ucf.edu/GPGPU/Compiling_a_MEX_file_with_Visual_Studio2.htm)
Create an empty Project, not a MFC Dll Project.
There is no need to *.def file.
There is no need to add "mexversion.rc" into your project.
There is no need to add "MATLAB_MEX_FILE" as a preprocessor definition.
I'm using JNI in Android development. I want to know where do the compiler find the referenced .h files?
Here in jni/jni_part.cpp, it includs lots of .h files. Opencv related files are defined by the SDK, but the "cartoon.h" is sure to be a project-specified header. But I cannot find it in the project folder. Then do the eclipse compile the JNI c++ code at every run? If so , in which directories does the eclipse find these headers?
Maybe it's basic for JNI but I'm not familiar with it. So plz help me out with one or two sentences. Or you could just paste a simple tutorial for JNI in Android, eclipse.
#include <jni.h>
#include <opencv2/core/core.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <opencv2/features2d/features2d.hpp>
#include "cartoon.h"
#include "ImageUtils.h" // Handy functions for debugging OpenCV images, by Shervin Emami.
using namespace std;
using namespace cv;
extern "C" {
.....
This is my eclipse project folder structure
/project
/jni
jni_part.cpp
/src
something.java
You'll need to start using android-ndk to compile the .c, .cpp files to a .so library object, which you can then use in your android project.
Please refer to the Android NDK to get started.
http://developer.android.com/tools/sdk/ndk/index.html#GetStarted
you can find examples in the NDK download.
If Eclipse "knows" where cartoon.h file is on disk, it will help you find it - put the cursor on that #include line and press F3.
Regarding your other question: Eclipse compiles only if the relevant files (sources, headers, or mk) change.
This might be a very dumb question...
I'm trying to use Boost.Python in an Xcode project (boost 1.50, xcode 4.4, OS X 10.8). I installed both boost and python through macports. I dragged the macports Python framework (/opt/local/Library/Frameworks/Python.framework) into the project and tried the most minimal program possible:
#include <boost/python.hpp>
int main(int argc, const char * argv[]) {
Py_Initialize();
Py_Finalize();
return 0;
}
and get:
/opt/local/include/boost/python/detail/wrap_python.hpp:50:11: fatal error: 'pyconfig.h' file not found
Do I need to explicitly add the framework header folder to the project's header search paths? That seems irregular... so hopefully I'm just misunderstanding something?