i have a problem to using a dll fortran in matlab.
i couldn't use a dll ,that is built by fortran, in matlab. i use "loadlibrary" instruction in matlab but the error is related to header files.
what is header files??
please give me more information to load a dll fortran in matlab and call it.
Rather than try to use a dll file directly I suggest you re-build it using Matlab's MEX functionality. Yes, a mex file is a dll and you can build dlls outside Matlab and use them successfully, it's a lot easier, for a beginner such as I guess you to be, to use MEX. One way in which it is easier is that, if you build a mex file, the system won't ask you for a header file which is, as you know, a rather foreign concept to a Fortran programmer. Another way in which MEX will make your life easier is that you can then call the function exposed by the dll directly from Matlab's command line, without loadlibrary.
Study the Matlab documentation on MEX files, pay particular attention to how to integrate Fortran this way.
Without seeing your header file and the command line you're using in MATLAB, it's hard to help you too much here. You might reference the documentation in MATLAB which request that you pass two arguments to loadlibrary, the second being the header file with function signatures. I am guessing you are not providing this second argument.
You need to provide a header file that defines each of the named functions in the Fortran DLL that you'll be calling. For instance, if your DLL contains a function named sum that sums two double precision variables, like:
function sum(a,b) result(sum)
real(kind=2), intent(in) :: a, b
real(kind=2) :: sum
sum = a + b
end function
Then your header will need to contain something like:
double sum(double*a, double*b);
But don't forget to decorate this with the name mangling specific to your Fortran compiler. For instance, if sum was in a module named foo, and you compiled with gfortran, then you will need something like:
double __foo_MOD_sum(double*a, double*b);
There are a lot of other cases, but that's the gist of it.
Related
In MATLAB, there are roughly 3 ways to define functions: non-comment-only .m files, .p files, and compiled code (e.g. DLL, MEX).
Knowing where a function is defined could be helpful in several cases, such as when a breaking change was introduced to some function outside our control, and we'd like to try to revert to an old version in the hopes of getting our code working again; or when trying to reverse-engineering some undisclosed algorithm.
The which function is usually very good at identifying function definitions and their locations (which works for .m, .p and MEX), but isn't very useful when it comes to shared library functions, where (at best) it points to a comment-only documentation file:
>> which _mcheck
built-in (undocumented)
>> which svd
built-in (D:\Program Files\MATLAB\R2019a\toolbox\matlab\matfun\svd)
If so, assuming a function found within a shared library is called during the execution of my code, how can I locate the specific file (DLL) that contains it?
It turns out that dbstop can be used for this. For example:
>> which svd
built-in (D:\Program Files\MATLAB\R2019a\toolbox\matlab\matfun\svd)
>> dbstop svd
Warning: Entering debug mode is only supported within running MATLAB code files.
Warning: MATLAB debugger can only stop in MATLAB code files, and "libmwmathlinalg>svd" is not a MATLAB code file.
Instead, the debugger will stop at the point right before "libmwmathlinalg>svd" is called.
From there's it's just a matter of finding a file called libmwmathlinalg (with the relevant extension) - which isn't a difficult task if your drive is indexed.
I was wondering if there is a way to create a '.exe' file from ' .m' file in MATLAB, such that it can be run in machine which does not have MATLAB (like it can be done in C, C++).
I know writing a MATLAB function is one way, but I am not sure if it can run in machine without MATLAB.
Also I would like to hide my code and just create a script which can be run by a user using his own data files.
The Matlab Compiler is the standard way to do this. mcc is the command. The Matlab Runtime is required to run the programs; I'm not sure if it can be directly integrated with the executable or not.
If you have MATLAB Compiler installed, there's a GUI option for compiling. Try entering
deploytool
in the command line. Mathworks does a pretty good job documenting how to use it in this video tutorial: http://www.mathworks.com/products/demos/compiler/deploytool/index.html
Also, if you want to include user input such as choosing a file or directory, look into
uigetfile % or uigetdir if you need every file in a directory
for use in conjunction with
guide
Try:
mcc -m yourfile
Also see help mcc
If your code is more of a data analysis routine (vs. visualization / GUI), try GNU Octave. It's free and many of its functions are compatible with MATLAB. (Not 100% but maybe 99.5%.)
mcc -?
explains that the syntax to make *.exe (Standalone Application) with *.m is:
mcc -m <matlabFile.m>
For example:
mcc -m file.m
will create file.exe in the curent directory.
It used to be possible to compile Matlab to C with older versions of Matlab. Check out other tools that Matlab comes with.
Newest Matlab code can be exported as a Java's jar or a .Net Dll, etc. You can then write an executable against that library - it will be obfuscated by the way. The users will have to install a freely available Matlab Runtime.
Like others mentioned, mcc / mcc.exe is what you want to convert matlab code to C code.
The "StandAlone" method to compile .m file (or files) requires a set of Matlab published library (.dll) files on a target (non-Matlab) platform to allow execution of the compiler generated .exe.
Check MATLAB main site for their compiler products and their limitations.
I developed a non-matlab software for direct compilation of m-files (TMC Compiler). This is an open-source converter of m-files projects to C. The compiler produces the C code that may be linked with provided open-source run-time library to produce a stand-alone application. The library implements a set of build-in functions; the linear-algebra operations use LAPACK code. It is possible to expand the set of the build-in functions by custom implementation as described in the documentation.
In MATLAB, you can declare a function dependency with:
%#function myExtraFunctionName
Doing so tells MATLAB that myExtraFunctionName is required by the script or function to operate, even if it's called by an eval statement or some other method that the various dependency checkers or compilers can't figure out.
I have several files that load in .mat or other data files that are required for the script to run, and I would like to include them in a similar manner so that when I run a dependency check with, say fList = matlab.codetools.requiredFilesAndProducts, it will find these data files as well. Ultimately what I would like to be able to do is generate the list of files and pass it to zip to archive every file required to run a given script or function, including data files.
Trying to find any documentation on this feature is challenging because the MATLAB help won't let you just type in %# and searching for %#function just searches for function. Google does the same thing: "hash percent function" returns lots of information on hash tables, "%#function matlab" strips out the important characters, and "declare matlab function" "declare matlab function dependency" turns up nothing useful. I don't remember where I encountered this syntax, so I don't even know if this is a documented feature or not.
I have two questions:
Can someone point me to documentation on this syntax along with some clues as to what keywords I should be using to search?
Can this be used to declare dependencies other than m-files and, if not, how can I go about doing that?
%#function is a pragma directive that informs MATLAB Compiler that the specified function will be called indirectly using feval, eval, or the like.
This is important because the static code analyzer will not be able to detect such dependencies on its own. For instance the name of the function could be stored in a string as in:
fcn = 'myFunction';
feval(fcn)
As far as I know, this is only used by the MATLAB Compiler, nothing else.
There are other similar pragmas. For example MATLAB Coder has %#codegen compiler directive.
I don't have any answer, but maybe you can use this website:
http://www.symbolhound.com/
It let you do search using symbols.
Environment:
Matlab R2012a (I have access to others if necessary)
All Toolboxes/Compiler installed
Ubuntu 12.04 64bit and/or Windows 7 64bit
I am working with the source for a software package written in Matlab (unfortunately its proprietary so no code examples...sorry), and one function briefly uses the Control System Toolbox and the Signal Processing Toolbox.
I have no problem running the code on my personal computer because I have every toolbox installed, however I would like to compile (mex or mcc) JUST the function using those two toolboxes. The goal, of course, is to run the software on a machine without those toolboxes, while leaving the remaining code open to change.
According to matlab, they have no problem with you compiling code that uses almost any toolbox. Here is the list of toolboxes that support mcc compilation:
http://www.mathworks.com/products/compiler/supported/compiler_support.html
The problem arises in that mcc no longer allows compiling with the -x option to create a mex-ed version of the function, so I'm forced to create a C executable (maybe? hopefully not). This particular function takes large matrices as parameters (impractical to write as a command line argument) and returns a structure of cell arrays.
The only way around this (as I see it now) would be to write the arguments (large matrices) to the hard drive in a binary .mat file , have the compiled C binary read in the arguments, run the algorithm, and finally save the return values in another .mat for the parent thread to load back into memory.
This seems totally impractical. I would greatly appreciate alternative suggestions. Please let me know if anything here in unclear. Thanks in advance!
[Edit 1] The codegen package does not support tf.m. It seems like this should be possible (and used to be possible with the mex -x option), but I'm at a loss. Any suggestions would be greatly appreciated!
I think the reason -x is not supported anymore is the fact that Matlab now has a product called "coder", which converts .m files to .c files and can also create .mex files from "suitable" .m files using the option -args to specify the input arguments: http://www.mathworks.com/videos/generating-c-code-from-matlab-code-68964.html
I would like to optimize a function written in Matlab by converting the code to C\C++. The result should be callable from within matlab, as it is a small part of a larger matlab code.
For example, converting my function to C code wrapped in a .mex file would work.
I heard matlab coder package can help with that.
As I am unfamiliar with this package, what is the quickest way to achieve this?
If you have a license for MATLAB Coder, then, yes, that is the correct package to use. The function you're looking for is codegen. There are restrictions on what can be used in code generation: to see if your function meets those restrictions, add the tag %#codegen to the beginning of your function as shown below
function foo(bar) %#codegen
<your code here>
and open the function file in the MATLAB editor. The tag tells the editor to check that the code complies with the rules for code generation. Once the editor shows that your code complies with those rules, generating the mex file may be as easy as
>> codegen foo
which would generate a mex-file, foo_mex in the current folder. For your particular function you may need to use some of the optional arguments for codegen to generate the mex-file properly.