FMI4cpp is a cross-platform FMI 2.0 implementation written in modern C++.
Influenced by it's spiritual brother FMI4j, it aims to be an easy to install, easy to use, object oriented and fast FMI implementation for C++.
FMI4cpp supports both Co-simulation and Model Exchange.
For Model Exchange, solvers from odeint can be used.
Because this library provides a clean, easy to use API and is easy to install (through vcpkg).
Recommended way is to install vcpkg and run:
./vcpkg install fmi4cppThe alternative is to fetch the dependencies manually, put them in the path somewhere and run the regular CMake install procedures.
Install vcpkg and run:
./vcpkg install boost-property-tree boost-ublas boost-odeint boost-program-options libzipThen tell CMake about your vcpkg installation by passing
-DCMAKE_TOOLCHAIN_FILE=C:\vcpkg\scripts\buildsystems\vcpkg.cmake to it.
Note that boost-ublas and boost-odeint are optional and can be omitted by passing -DFMI4CPP_WITH_ODEINT=OFF to CMake.
Similarly, boost-program-options can be omitted by passing -DFMI4CPP_BUILD_TOOL=OFF.
On *NIX systems the dependencies can of course be installed using the native package handler.
sudo apt-get install libzip-dev libboost-dev libboost-test-dev#include <fmi4cpp/fmi2/fmi2.hpp>
#include <fmi4cpp/common/logger.hpp>
using namespace fmi4cpp::fmi2;
namespace logger = fmi4cpp::logger;
const double stop = 10.0;
const double stepSize = 1.0/100;
int main() {
Fmu fmu("path/to/fmu.fmu");
auto cs_fmu = fmu.asCoSimulationFmu();
auto me_fmu = fmu.asModelExchangeFmu();
auto cs_md = fmu->getModelDescription(); //smart pointer to a CoSimulationModelDescription instance
logger::info("modelIdentifier={}", cs_fmu->getModelDescription()->modelIdentifier());
auto me_md = fmu->getModelDescription(); //smart pointer to a ModelExchangeModelDescription instance
logger::info("modelIdentifier={}", me_fmu->getModelDescription()->modelIdentifier());
auto var = cs_md->getVariableByName("my_var").asRealVariable();
logger::info("Name={}, start={}", var.name(), var.start().value_or(0));
auto slave = cs_fmu->newInstance();
// or
// auto solver = make_solver<RK4ClassicSolver>(1E-3);
// auto slave = me_fmu->newInstance(solver);
slave->setupExperiment();
slave->enterInitializationMode();
slave->exitInitializationMode();
double t;
double value;
while ( (t = slave->getSimulationTime()) <= stop) {
if (!slave->doStep(stepSize)) {
logger::error("Error! doStep() returned with status: {}", to_string(slave->getLastStatus()));
break;
}
if (!var.read(*slave, value)) {
logger::error("Error! readReal() returned with status: {}", to_string(slave->getLastStatus()));
break;
}
logger::info("t={}, {}={}", t, var.name(), value);
}
slave->terminate();
}FMI4cpp comes with a simple CLI for testing FMUs, called fmu_driver.
Options:
-h [ --help ] Print this help message and quits.
-f [ --fmu ] arg Path to FMU.
-o [ --output ] arg Where to store the generated CSV results.
--start arg Start time.
--stop arg Stop time.
--stepsize arg StepSize.
--me Treat FMU as an Model Exchange FMU.
-v [ --variables ] arg Variables to print.In order to run the example/test code, a system variable named TEST_FMUs must be present on your system. This variable should point to the location of the content found here.
The examples are built by default. To change this pass -DFMI4CPP_BUILD_EXAMPLES=OFF to CMake.
Test are on the other hand not built by default. To change this pass -DFMI4CPP_BUILD_TESTS=ON to CMake.
To run the tests you will need an additional dependency:
./vcpkg install boost-test