How to use CMake and Visual Studio 2010 (64 bit) to build a MATLAB R2011a (64 bit) mex file? - matlab

I would like to write a CMakeLists.txt such that CMake writes a Visual Studio 2010 (64 bit) solution file to build a mex function for MATLAB R2011a (64 bit) from C++ code example.cxx.
I do not want to use MATLAB's compiler wrapper mex but set up the Visual Studio solution file such that Visual C++ links the relevant MATLAB libraries.
example.cxx has no dependencies except for the MATLAB libraries that are necessary for mex files.
CMake 2.8.7 is set up correctly such that it uses the 64 bit generator for Visual Studio 2010.
The essence of what I am doing right now is
find_package(Matlab)
add_library(example STATIC example.cxx)
target_link_libraries(example ${MATLAB_LIBRARIES})
Neither the compiler nor the linker issues any errors. I install the output example.lib under the name example.mexw64 in a directory in MATLAB's path. When I call example from MATLAB, I get the error message
??? Invalid MEX-file
'C:\...\example.mexw64':
C:\...\example.mexw64 is not a valid Win32 application.
Any suggestions are welcome!

I had the same problem and this link was very helpful (also serves as a nice example of how to use ITK in a MATLAB MEX file btw). I think for your case, you need to add the link flag "/export:mexFunction" to your CMakeLists.txt file. Example below:
PROJECT(example)
FIND_PACKAGE(Matlab REQUIRED)
INCLUDE_DIRECTORIES(${MATLAB_INCLUDE_DIR})
ADD_LIBRARY(example MODULE example.cpp)
ADD_DEFINITIONS(-DMATLAB_MEX_FILE)
# Needed for entry point.
SET_TARGET_PROPERTIES(example
PROPERTIES
LINK_FLAGS "/export:mexFunction"
)
# Change the dll extension to a mex extension.
set_target_properties(example PROPERTIES SUFFIX ".mexw64")
TARGET_LINK_LIBRARIES(example ${MATLAB_LIBRARIES})
Note that the FIND_PACKAGE(Matlab) doesn't seem to work all that well, so that may be a problem for some people. I had to get around it by hard-coding the MATLAB paths into CMakeLists.txt (not shown in this example).

Matlab mex files are dll`s not libs. Try making cmake (not an expert on that) create a dynamic librart، not static.

Related

MATLAB no longer supports user-defined MEX configuration?

I've upgraded my MATLAB to 2014b (on OS X 10.10), and tried to test some old MEX C/C++ codes.
As usual, I run mex -setup from the command window, and I would expect to be provided the chance to overwrite the option file "meshopt.sh".
But now, it seems MATLAB has made some change and I am not allowed to change the MEX configuration, it simply says:
MEX configured to use Xcode with Clang for C language compilation,
...
to choose a different language, select one from the following
mex -setup C++
mex -setup FORTRAN
So, is it true that the old ways to modify "mexopts.sh" are no longer feasible?
It seems that the following command works:
mex -setup my_mexopts.sh
however, there's some warning information,
Legacy MEX infrastructure is provided for compatibility; it will be removed in a future version of MATLAB.
Apart from that, everything looks fine, except I got some warning at compile time seems due to compiler version(gcc 4.9.1) on my current system(OS X 10.10).
gcc: warning: couldn't understand kern.osversion '14.0.0
When I run mex -setup C, I see information like the following:
Microsoft Visual C++ 2008 (C) mex -setup:H:\MATLAB\R2014b\bin\win64\mexopts\msvc2008.xml C
Microsoft Visual C++ 2010 (C) mex -setup:H:\MATLAB\R2014b\bin\win64\mexopts\msvc2010.xml C
Microsoft Visual C++ 2012 (C) mex -setup:H:\MATLAB\R2014b\bin\win64\mexopts\msvc2012.xml C
The mex part is actually a link you can click to choose that configuration. So, to make your own:
Choose an xml as a template and copy it. (e.g I'd copy H:\MATLAB\R2014b\bin\win64\mexopts\msvc2012.xml to %AppData%\MathWorks\MATLAB\R2014b\mex_C++_win64_custom.xml).
Make the edits in the XML file, probably in the <vars> tag (e.g. modify COMPFLAGS or CFLAGS whatever variable has your compiler options) or the <env> tag (e.g. PATH, INCLUDE, LIB, etc.)
Set that to the current configuration:
mex -setup:C:\[YourMATLABAppDataHere]\myCopts.xml C
Note that a good place in Windows to keep settings is under %APPDATA%. For MATLAB R2014b, this would be something like C:\Users\[yourname]\AppData\Roaming\MathWorks\MATLAB\R2014b.
Do the same for C++ or FORTRAN configurations too.

Mex cannot find a file, but "which" can

I am trying to compile a C++ function (found here). I downloaded the requisite packages, installed Microsoft Windows SDK 7.1, linked it to MATLAB using mex -setup, and then unzipped the function packages into my MATLAB path.
When I run the command:
mex -output Faddeeva_w -O Faddeeva_w_mex.cc Faddeeva.cc
I get the error message:
C:\PROGRA~1\MATLAB\R2013A\BIN\MEX.PL: Error: 'Faddeeva_w_mex.cc' not found.
But if I type which Faddeeva_w_mex.cc I get:
C:\Users\craigim\Documents\Code\Matlab\Faddeeva-MATLAB\Faddeeva_w_mex.cc
So MATLAB and the which command have no problems finding the file, but mex is lost. This is my very first attempt at compiling something with mex, so I'm really not sure where to start here. Does mex have a different path variable that I have to set?
I'm using MATLAB 2013a on a Windows 7 64bit machine with the version of SDK 7.1 that was linked from the MATLAB List of supported compilers.
Either cd into the directory containing the files (assuming they both in the same place), or specify full/relative path to the C++ files when invoking mex function
Try putting addpath('C:\Users\craigim\Documents\Code\Matlab\Faddeeva-MATLAB\'); in your m-file. The path that MATLAB uses seems to be internal and independent of whatever your OS is using.
Documentation on addpath here.
And a similar discussion here.
You may also have to set your PATH environment variable to the string returned by the command fullfile(matlabroot,'bin',computer('arch')) in MATLAB. Here are some instructions on setting environment variables for Windows and Mac or Linux
There is also a pretty good overview of building mex-files here although I get the impression that the basics are not going to answer your question.

using visual C++ compiler in matlab

i installed two compilers in Matlab : LCC and Visual C++ 2008
i want to load a C++ header file in matlab but when i want to do this matlab uses LCC instead of
Visual C++ and gives me some warnings .
i used:
mex -setup
mbuild -setup
but Matlab still uses LCC for loading my C++ header file
>> loadlibrary('DLLing.dll', 'DLLTutorial.h')
Warning: Message from C preprocessor:
lcc preprocessor error: C:\Users\MAHNAZ\Documents\MATLAB\DLLTutorial.h:3 Could not find include file
How can i say to Matlab that use visual c++ compiler instead of LCC??
What version of MatLab are you using? It might not suppose the version of the Microsoft SDK you have installed on your computer. This isn't really an answer but I can't post comments yet.
As per your description, after you type mex -setup, the first thing MATLAB should ask you:
Please choose your compiler for building external interface (MEX) files:
Would you like mex to locate installed compilers [y]/n?
After this, you should press y and then you should see a list of available compilers. Choose a right one from them.
What version of Windows are you working with, is it 32 or 64 bit (question for both Windows and the MATLAB version installed)?
Looking the archived documentation for R2008a (you must be logged in to see the page), it seems that LOADLIBRARY requires VS2005 on 64-bit platforms (perhaps it defaults to LCC if its not available). The truth is it does not explicitly say how it determines what compiler to use. (If you are up to it, you can edit loadlibrary.m and trace the execution to see why it ends up calling LCC instead of Visual C++)
Compare this with the current R2012a help page where it clearly says that you must select the compiler with mex -setup.
Note that LCC compiler will no longer be shipped with future versions.

How to start SVM training on MATLAB

I have a set of facial features that i have obtained and would like to classify using SVM. I intend to use libsvm package and use MATLAB to carry out the training.I have already read up on SVM by watching the Stanford lecture. But I am not sure how to use libsvm to start.. Need some guidance...
In matlab you can link your matlab code with some programs implemented in c. This a called a mex-file.
However you need to compile them, to make it work.
You can read the readme file to know how to compile them:
Installation
On Unix systems, we recommend using GNU g++ as your compiler and type
'make' to build 'svmtrain.mexglx' and 'svmpredict.mexglx'. Note that
we assume your MATLAB is installed in '/usr/local/matlab', if not,
please change MATLABDIR in Makefile.
Example:
linux> make
To use Octave, type 'make octave':
Example: linux> make octave
On Windows systems, pre-built binary files are already in the
directory `..\windows', so no need to conduct installation. Now we
include both 32bit binary files and 64bit binary files, but in future
releases, we will provide binary files only for 64bit MATLAB on
Windows. If you have modified the sources and would like to re-build
the package, type 'mex -setup' in MATLAB to choose a compiler for mex
first. Then type 'make' to start the installation.
Example:
matlab> mex -setup
(ps: MATLAB will show the following messages to setup default compiler.)
Please choose your compiler for building external interface (MEX) files:
Would you like mex to locate installed compilers [y]/n? y
Select a compiler:
1 Microsoft Visual C/C++ version 7.1 in C:\Program Files\Microsoft Visual Studio
[0] None
Compiler: 1
Please verify your choices:
Compiler: Microsoft Visual C/C++ 7.1
Location: C:\Program Files\Microsoft Visual Studio
Are these correct?([y]/n): y
matlab> make
For list of supported/compatible compilers for MATLAB, please check
the following page:
http://www.mathworks.com/support/compilers/current_release/

How to install a compiler on Windows? (For a Matlab program)

I have downloaded this code;
http://www.cs.sfu.ca/%7Emori/research/superpixels/superpixels64.tar.gz
In the readme file, it says;
Run mex -largeArrayDims on *.c in yu_imncut directory
-largeArrayDims is needed for 64bit architectures (thanks to Richard Lowe for providing fixes for 64bit MATLAB)
Obtain mfm-pb boundary detector code from
http://www.cs.berkeley.edu/projects/vision/grouping/segbench/
Change path names in sp_demo.m and pbWrapper.m
Get a fast processor and lots of RAM
Run sp_demo.m
I tried to do the mex -.. one but it told me that I don't have any compiler. How can I fix this? Can you please help me with this? I am using 64 bit Windows 7
As far as I know GCC for Windows is not supported by Matlab. Visual Studio Express Editions will work, but 2010 may require a patch dependent on the version of Matlab you are running (http://www.mathworks.com/support/compilers/R2011a/win32.html). This page lists all supported compilers for Matlab.
Here's a link to GCC for windows
http://gcc.gnu.org/install/specific.html#windows