FindMatlab

Finds Matlab or Matlab Compiler Runtime (MCR) and provides Matlab tools, libraries and compilers to CMake.

This package primary purpose is to find the libraries associated with Matlab or the MCR in order to be able to build Matlab extensions (mex files). It can also be used:

• to run specific commands in Matlab in case Matlab is available
• for declaring Matlab unit test
• to retrieve various information from Matlab (mex extensions, versions and release queries, …)

The module supports the following components:

• ENG_LIBRARY and MAT_LIBRARY: respectively the ENG and MAT libraries of Matlab
• MAIN_PROGRAM the Matlab binary program. Note that this component is not available on the MCR version, and will yield an error if the MCR is found instead of the regular Matlab installation.
• MEX_COMPILER the MEX compiler.
• MCC_COMPILER the MCC compiler, included with the Matlab Compiler add-on.
• SIMULINK the Simulink environment.

The variable Matlab_ROOT_DIR may be specified in order to give the path of the desired Matlab version. Otherwise, the behaviour is platform specific:

• Windows: The installed versions of Matlab/MCR are retrieved from the Windows registry
• OS X: The installed versions of Matlab/MCR are given by the MATLAB default installation paths in /Application. If no such application is found, it falls back to the one that might be accessible from the PATH.
• Unix: The desired Matlab should be accessible from the PATH. This does not work for MCR installation and Matlab_ROOT_DIR should be specified on this platform.

Additional information is provided when MATLAB_FIND_DEBUG is set. When a Matlab/MCR installation is found automatically and the MATLAB_VERSION is not given, the version is queried from Matlab directly (on Windows this may pop up a Matlab window) or from the MCR installation.

The mapping of the release names and the version of Matlab is performed by defining pairs (name, version). The variable MATLAB_ADDITIONAL_VERSIONS may be provided before the call to the find_package() in order to handle additional versions.

A Matlab scripts can be added to the set of tests using the matlab_add_unit_test(). By default, the Matlab unit test framework will be used (>= 2013a) to run this script, but regular .m files returning an exit code can be used as well (0 indicating a success).

Module Input Variables

Users or projects may set the following variables to configure the module behaviour:

Matlab_ROOT_DIR

the root of the Matlab installation.

MATLAB_FIND_DEBUG

outputs debug information

MATLAB_ADDITIONAL_VERSIONS

additional versions of Matlab for the automatic retrieval of the installed versions.

Variables defined by the module

Result variables

Matlab_FOUND

TRUE if the Matlab installation is found, FALSE otherwise. All variable below are defined if Matlab is found.

Matlab_ROOT_DIR

the final root of the Matlab installation determined by the FindMatlab module.

Matlab_MAIN_PROGRAM

the Matlab binary program. Available only if the component MAIN_PROGRAM is given in the find_package() directive.

Matlab_INCLUDE_DIRS

the path of the Matlab libraries headers

Matlab_MEX_LIBRARY

library for mex, always available.

Matlab_MX_LIBRARY

mx library of Matlab (arrays), always available.

Matlab_ENG_LIBRARY

Matlab engine library. Available only if the component ENG_LIBRARY is requested.

Matlab_MAT_LIBRARY

Matlab matrix library. Available only if the component MAT_LIBRARY is requested.

Matlab_ENGINE_LIBRARY

Matlab C++ engine library, always available for R2018a and newer.

Matlab_DATAARRAY_LIBRARY

Matlab C++ data array library, always available for R2018a and newer.

Matlab_LIBRARIES

the whole set of libraries of Matlab

Matlab_MEX_COMPILER

the mex compiler of Matlab. Currently not used. Available only if the component MEX_COMPILER is requested.

Matlab_MCC_COMPILER

the mcc compiler of Matlab. Included with the Matlab Compiler add-on. Available only if the component MCC_COMPILER is requested.

Cached variables

Matlab_MEX_EXTENSION

the extension of the mex files for the current platform (given by Matlab).

Matlab_ROOT_DIR

the location of the root of the Matlab installation found. If this value is changed by the user, the result variables are recomputed.

Provided macros

matlab_get_version_from_release_name()

returns the version from the release name

matlab_get_release_name_from_version()

returns the release name from the Matlab version

Provided functions

matlab_add_mex()

adds a target compiling a MEX file.

matlab_add_unit_test()

adds a Matlab unit test file as a test to the project.

matlab_extract_all_installed_versions_from_registry()

parses the registry for all Matlab versions. Available on Windows only. The part of the registry parsed is dependent on the host processor

matlab_get_all_valid_matlab_roots_from_registry()

returns all the possible Matlab or MCR paths, according to a previously given list. Only the existing/accessible paths are kept. This is mainly useful for the searching all possible Matlab installation.

matlab_get_mex_suffix()

returns the suffix to be used for the mex files (platform/architecture dependent)

matlab_get_version_from_matlab_run()

returns the version of Matlab/MCR, given the full directory of the Matlab/MCR installation path.

Known issues

Symbol clash in a MEX target

By default, every symbols inside a MEX file defined with the command matlab_add_mex() have hidden visibility, except for the entry point. This is the default behaviour of the MEX compiler, which lowers the risk of symbol collision between the libraries shipped with Matlab, and the libraries to which the MEX file is linking to. This is also the default on Windows platforms.

However, this is not sufficient in certain case, where for instance your MEX file is linking against libraries that are already loaded by Matlab, even if those libraries have different SONAMES. A possible solution is to hide the symbols of the libraries to which the MEX target is linking to. This can be achieved in GNU GCC compilers with the linker option -Wl,--exclude-libs,ALL.

Tests using GPU resources

in case your MEX file is using the GPU and in order to be able to run unit tests on this MEX file, the GPU resources should be properly released by Matlab. A possible solution is to make Matlab aware of the use of the GPU resources in the session, which can be performed by a command such as D = gpuDevice() at the beginning of the test script (or via a fixture).

Reference

Matlab_ROOT_DIR

The root folder of the Matlab installation. If set before the call to find_package(), the module will look for the components in that path. If not set, then an automatic search of Matlab will be performed. If set, it should point to a valid version of Matlab.

MATLAB_FIND_DEBUG

If set, the lookup of Matlab and the intermediate configuration steps are outputted to the console.

MATLAB_ADDITIONAL_VERSIONS

If set, specifies additional versions of Matlab that may be looked for. The variable should be a list of strings, organised by pairs of release name and versions, such as follows:

set(MATLAB_ADDITIONAL_VERSIONS
    "release_name1=corresponding_version1"
    "release_name2=corresponding_version2"
    ...
    )

Example:

set(MATLAB_ADDITIONAL_VERSIONS
    "R2013b=8.2"
    "R2013a=8.1"
    "R2012b=8.0")

The order of entries in this list matters when several versions of Matlab are installed. The priority is set according to the ordering in this list.

matlab_get_version_from_release_name

Returns the version of Matlab (17.58) from a release name (R2017k)

matlab_get_release_name_from_version

Returns the release name (R2017k) from the version of Matlab (17.58)

matlab_extract_all_installed_versions_from_registry

This function parses the registry and founds the Matlab versions that are installed. The found versions are returned in matlab_versions. Set win64 to TRUE if the 64 bit version of Matlab should be looked for The returned list contains all versions under HKLM\\SOFTWARE\\Mathworks\\MATLAB and HKLM\\SOFTWARE\\Mathworks\\MATLAB Runtime or an empty list in case an error occurred (or nothing found).

Note

Only the versions are provided. No check is made over the existence of the installation referenced in the registry,

matlab_get_all_valid_matlab_roots_from_registry

Populates the Matlab root with valid versions of Matlab or Matlab Runtime (MCR). The returned matlab_roots is organized in triplets (type,version_number,matlab_root_path), where type indicates either MATLAB or MCR.

matlab_get_all_valid_matlab_roots_from_registry(
    matlab_versions
    matlab_roots)

matlab_versions

the versions of each of the Matlab or MCR installations

matlab_roots

the location of each of the Matlab or MCR installations

matlab_get_mex_suffix

Returns the extension of the mex files (the suffixes). This function should not be called before the appropriate Matlab root has been found.

matlab_get_mex_suffix(
    matlab_root
    mex_suffix)

matlab_root

the root of the Matlab/MCR installation

mex_suffix

the variable name in which the suffix will be returned.

matlab_get_version_from_matlab_run

This function runs Matlab program specified on arguments and extracts its version. If the path provided for the Matlab installation points to an MCR installation, the version is extracted from the installed files.

matlab_get_version_from_matlab_run(
    matlab_binary_path
    matlab_list_versions)

matlab_binary_path

the location of the matlab binary executable

matlab_list_versions

the version extracted from Matlab

matlab_add_unit_test

Adds a Matlab unit test to the test set of cmake/ctest. This command requires the component MAIN_PROGRAM and hence is not available for an MCR installation.

The unit test uses the Matlab unittest framework (default, available starting Matlab 2013b+) except if the option NO_UNITTEST_FRAMEWORK is given.

The function expects one Matlab test script file to be given. In the case NO_UNITTEST_FRAMEWORK is given, the unittest script file should contain the script to be run, plus an exit command with the exit value. This exit value will be passed to the ctest framework (0 success, non 0 failure). Additional arguments accepted by add_test() can be passed through TEST_ARGS (eg. CONFIGURATION <config> ...).

matlab_add_unit_test(
    NAME <name>
    UNITTEST_FILE matlab_file_containing_unittest.m
    [CUSTOM_TEST_COMMAND matlab_command_to_run_as_test]
    [UNITTEST_PRECOMMAND matlab_command_to_run]
    [TIMEOUT timeout]
    [ADDITIONAL_PATH path1 [path2 ...]]
    [MATLAB_ADDITIONAL_STARTUP_OPTIONS option1 [option2 ...]]
    [TEST_ARGS arg1 [arg2 ...]]
    [NO_UNITTEST_FRAMEWORK]
    )

The function arguments are:

NAME

name of the unittest in ctest.

UNITTEST_FILE

the matlab unittest file. Its path will be automatically added to the Matlab path.

CUSTOM_TEST_COMMAND

Matlab script command to run as the test. If this is not set, then the following is run: runtests('matlab_file_name'), exit(max([ans(1,:).Failed])) where matlab_file_name is the UNITTEST_FILE without the extension.

UNITTEST_PRECOMMAND

Matlab script command to be ran before the file containing the test (eg. GPU device initialisation based on CMake variables).

TIMEOUT

the test timeout in seconds. Defaults to 180 seconds as the Matlab unit test may hang.

ADDITIONAL_PATH

a list of paths to add to the Matlab path prior to running the unit test.

MATLAB_ADDITIONAL_STARTUP_OPTIONS

a list of additional option in order to run Matlab from the command line. -nosplash -nodesktop -nodisplay are always added.

TEST_ARGS

Additional options provided to the add_test command. These options are added to the default options (eg. “CONFIGURATIONS Release”)

NO_UNITTEST_FRAMEWORK

when set, indicates that the test should not use the unittest framework of Matlab (available for versions >= R2013a).

WORKING_DIRECTORY

This will be the working directory for the test. If specified it will also be the output directory used for the log file of the test run. If not specified the temporary directory ${CMAKE_BINARY_DIR}/Matlab will be used as the working directory and the log location.

matlab_add_mex

Adds a Matlab MEX target. This commands compiles the given sources with the current tool-chain in order to produce a MEX file. The final name of the produced output may be specified, as well as additional link libraries, and a documentation entry for the MEX file. Remaining arguments of the call are passed to the add_library() or add_executable() command.

matlab_add_mex(
    NAME <name>
    [EXECUTABLE | MODULE | SHARED]
    SRC src1 [src2 ...]
    [OUTPUT_NAME output_name]
    [DOCUMENTATION file.txt]
    [LINK_TO target1 target2 ...]
    [R2017b | R2018a]
    [EXCLUDE_FROM_ALL]
    [...]
)

NAME

name of the target.

SRC

list of source files.

LINK_TO

a list of additional link dependencies. The target links to libmex and libmx by default.

OUTPUT_NAME

if given, overrides the default name. The default name is the name of the target without any prefix and with Matlab_MEX_EXTENSION suffix.

DOCUMENTATION

if given, the file file.txt will be considered as being the documentation file for the MEX file. This file is copied into the same folder without any processing, with the same name as the final mex file, and with extension .m. In that case, typing help <name> in Matlab prints the documentation contained in this file.

R2017b or R2018a may be given to specify the version of the C API

to use: R2017b specifies the traditional (separate complex) C API, and corresponds to the -R2017b flag for the mex command. R2018a specifies the new interleaved complex C API, and corresponds to the -R2018a flag for the mex command. Ignored if MATLAB version prior to R2018a. Defaults to R2017b.

MODULE or SHARED may be given to specify the type of library to be

created. EXECUTABLE may be given to create an executable instead of a library. If no type is given explicitly, the type is SHARED.

EXCLUDE_FROM_ALL

This option has the same meaning as for EXCLUDE_FROM_ALL and is forwarded to add_library() or add_executable() commands.

The documentation file is not processed and should be in the following format:

% This is the documentation
function ret = mex_target_output_name(input1)