FunctionParser
vtk-examples/Cxx/Utilities/FunctionParser
Description¶
This example shows how to substitute values and evaluate a string such as "a+b".
Other languages
See (Java)
Question
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Code¶
FunctionParser.cxx
#include <vtkFunctionParser.h>
#include <vtkNew.h>
int main(int, char*[])
{
vtkNew<vtkFunctionParser> functionParser;
functionParser->SetFunction("a+b");
functionParser->SetScalarVariableValue("a", 2);
functionParser->SetScalarVariableValue("b", 3);
double result = functionParser->GetScalarResult();
std::cout << "result: " << result << std::endl;
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(FunctionParser)
find_package(VTK COMPONENTS
vtkCommonCore
vtkCommonMisc
QUIET
)
if (NOT VTK_FOUND)
message("Skipping FunctionParser: ${VTK_NOT_FOUND_MESSAGE}")
return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
# old system
include(${VTK_USE_FILE})
add_executable(FunctionParser MACOSX_BUNDLE FunctionParser.cxx )
target_link_libraries(FunctionParser PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(FunctionParser MACOSX_BUNDLE FunctionParser.cxx )
target_link_libraries(FunctionParser PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS FunctionParser
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build FunctionParser¶
Click here to download FunctionParser and its CMakeLists.txt file. Once the tarball FunctionParser.tar has been downloaded and extracted,
cd FunctionParser/build
If VTK is installed:
cmake ..
If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:
cmake -DVTK_DIR:PATH=/home/me/vtk_build ..
Build the project:
make
and run it:
./FunctionParser
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.