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PyBind11: simple invoke task, standard C++ library not found

i am trying to wrap the C++ library PyrochloreAFM.hpp which itself uses the lib boost/randoom.hpp so that i can import it as a python module. The C++ part itself works fine and i can succesfully import and use all of this from my main.
#include "PyrochloreAFM.hpp"
int main (int argc, const char *argv[]) {
PyrochloreAFM pyrochloreAFM (&parameters, &statistics, &rng);
}
Now following a tutorial i set up my c++ wrapper:
// pybind11_wrapper.cpp
#include <pybind11/pybind11.h>
#include <PyrochloreAFM.hpp>
PYBIND11_MODULE(pybind11_example, m) {
m.doc() = "pybind11 example plugin"; // Optional module docstring
m.def("cpp_function", &PyrochloreAFM, "A function that multiplies two numbers");
}
and my tasks.py file
# tasks.py
import invoke
invoke.run(
"g++ -O3 -Wall -Werror -shared -std=c++11 -fPIC PyrochloreAFM.cpp "
"-o libpyro.so "
)
However now $invoke build-PyrochloreAFM or even $invoke --list seem to have lost the track of the standard C++ library.
In file included from PyrochloreAFM.cpp:1:
./Parameters.hpp:16:10: fatal error: 'boost/random.hpp' file not found
#include "boost/random.hpp" // tested with boost 1.53
^~~~~~~~~~~~~~~~~~
1 error generated.
This might be a simple PATH problem so i would be very glad for any tips!
Thank you, Andres!

"Of course" the tasks.py file which compiles the .cpp file through the python module invoke has to instruct the compiler g++ to use the libraries we desire. In my case it is the flag -I /opt/homebrew/Cellar/boost/1.80.0/include i also use in my makefile or directly in terminal.

Issue with SWIG for creating Python bindings for C library

I want to use SWIG to create Python bindings for C library, but I have some troubles with it. I used the following .c and .i files from tutorial.
example.c
/* Compute factorial of n */
int fact(int n) {
if (n <= 1)
return 1;
else
return n*fact(n-1);
}
/* Compute n mod m */
int my_mod(int n, int m) {
return(n % m);
}
double My_variable;
example.i
%module example
%{
extern double My_variable;
extern int fact(int);
extern int my_mod(int n, int m);
%}
extern double My_variable;
extern int fact(int);
extern int my_mod(int n, int m);
Commands that I used:
$ swig -python -py3 example.i
$ gcc -c -fpic example.c example_wrap.c -I/usr/include/python3.6
$ gcc -shared example.o example_wrap.o -o example.so
And when I try to import it in python3 I am getting this
>>> import example
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: dynamic module does not define module export function (PyInit_example)
Any help appreciated

SWIG generates a module with underscore prepended by default, so you'll get a module called _example which needs to be in _example.so.
This is explained in the SWIG documentation 34.2.3 Hand compiling a dynamic module:
While the preferred approach to building an extension module is to use the distutils, some people like to integrate building extensions with a larger build system, and thus may wish to compile their modules without the distutils. To do this, you need to compile your program using commands like this (shown for Linux):
$ swig -python example.i
$ gcc -O2 -fPIC -c example.c
$ gcc -O2 -fPIC -c example_wrap.c -I/usr/local/include/python2.5
$ gcc -shared example.o example_wrap.o -o _example.so
The exact commands for doing this vary from platform to platform. However, SWIG tries to guess the right options when it is installed. Therefore, you may want to start with one of the examples in the SWIG/Examples/python directory. If that doesn't work, you will need to read the man-pages for your compiler and linker to get the right set of options. You might also check the SWIG Wiki for additional information.
When linking the module, the name of the output file has to match the name of the module prefixed by an underscore. If the name of your module is example, then the name of the corresponding object file should be _example.so or _examplemodule.so. The name of the module is specified using the %module directive or the -module command line option.
Compatibility Note: In SWIG-1.3.13 and earlier releases, module names did not include the leading underscore. This is because modules were normally created as C-only extensions without the extra Python support file (instead, creating Python code was supported as an optional feature). This has been changed in SWIG-1.3.14 and is consistent with other Python extension modules. For example, the socket module actually consists of two files; socket.py and _socket.so. Many other built-in Python modules follow a similar convention.

Run compiled python script with arguments in C++ (Cython)

What I try to achieve is compiling my Python script to lib/dll and invoke it with arguments.
This is my setup.py file for the script:
from distutils.core import setup
from Cython.Build import cythonize
setup(
ext_modules = cythonize("nu3k2nu4k.py")
)
Used this command to produce compilation outputs:
python setup.py build_ext --inplace
following files produced:
nu3k2nu4k.c
nu3k2nu4k.cp36-win_amd64.pyd
nu3k2nu4k.pyx
and a subdirectory named build which contains:
nu3k2nu4k.cp36-win_amd64.exp
nu3k2nu4k.cp36-win_amd64.lib
nu3k2nu4k.obj
How can I invoke the compiled script from c++ code with arguments?
I used Cython for the task but that's not mandatory, boost or others could be used as well (I'm doing this to make the source code not accessible).
Edit:
Using the documentation provided by Mykola Shchetinin I have managed to generate an API header file for my script. I basically added a cdef api keyword to my main function. While this does help me export the method name to c++ I still need a way to pass around some arguments to my script. Since I pass string arguments I was hoping for a similar way like using PyRun to set argv and parse the arguments from the script (since I would like to avoid conversion of strings from c to python encoding if possible) Is there any easy way to pass those string arguments?
EDIT 2:
I got it working! following the sample provided by Mykola and directly compiling the c file output instead of using the .lib I got it working.

I have tried to do that by myself. So I convert char * to bytes in cython. (according to docs)
That is what I came up with. I have the following setup (gcc and centos7.2):
setup.py
from distutils.core import setup
from Cython.Build import cythonize
setup(
ext_modules = cythonize("func.pyx")
)
main.c
#include "Python.h"
#include "func.h"
int main() {
Py_Initialize();
initfunc();
func("0123hello jorghy!!");
Py_Finalize();
return 0;
}
func.pyx
cdef public func(char * arg):
cdef bytes py_bytes = arg
print(str(py_bytes));
I build all this stuff with the following commands:
python setup.py build_ext --inplace
gcc -I/usr/include/python2.7 -lpython2.7 -Wall -Wextra -O2 -g -o test main.c func.c
Then when running the executable file test I get the following results:
0123hello jorghy!!
UPDATE
There is another way to approach this problem:
I have created a cython file test.pyx:
import sys
if __name__ == "__main__":
print("hei")
print(sys.argv)
And compiled as an executable it using commands:
cython test.pyx --embed
gcc -I/usr/include/python2.7 -lpython2.7 -Wall -Wextra -O2 -g -o test test.c
Then you can call this code as an executable file:
$ ./test 1 2 3
hei
['./test', '1', '2', '3']
Then you can call it from C++ using std::system or other (better) methods.

Issue in Compling C++ method in Eclipse and calling C++ method from python

Simple C++ example class I want to talk to in a file called foo.cpp
#include <iostream>
Since ctypes can only talk to C functions, you need to provide those declaring them as extern "C"
extern "C" {
Foo* Foo_new(){ return new Foo(); }
void Foo_bar(Foo* foo){ foo->bar(); }
}
class Foo{
public:
void bar(){
std::cout << "Hello" << std::endl;
}
};
compile this to a shared library
g++ -c -fPIC foo.cpp -o foo.o
g++ -shared -Wl,-soname,libfoo.so -o libfoo.so foo.o
finally I have wrote python wrapper
from ctypes import cdll
lib = cdll.LoadLibrary('./libfoo.so')
class Foo(object):
def __init__(self):
self.obj = lib.Foo_new()
def bar(self):
lib.Foo_bar(self.obj)
f = Foo()
f.bar() #prints "Hello" on the screen
"My main intension is to compile C++ code in eclipse and call the C++ function from python in Linux". This works fine when I compiled C++ code in Linux and call the C++ method from python in Linux. But it doesn't work if I compile C++ code in eclipse and call the C++ method from python in Linux.
Error message:
symbol not found
I am new to the eclipse tool chain, But I am giving compiler option and linking option in as in this
g++ -c -fPIC foo.cpp -o foo.o
g++ -shared -Wl,-soname,libfoo.so -o libfoo.so foo.o
Snapshot of eclipse compiler option and linking option will be highly appreciated. Please help me in sorting out this issue. Thanks in advance

You need to create two projects in the Eclipse.
Makefile project with existing code. (File->New->Makefile project with existing code). In this project you must point to your foo.cpp file. Then in the project folder you must create file which name is "Makefile". Makefile must contain folowing lines:
all:
g++ -c -fPIC foo.cpp -o foo.o
g++ -shared -W1,-soname,libfoo.so -o libfoo.so foo.o
clean:
rm -f libfoo.so
Then You must create rules ("all" and "clean") for this project in the "Make Target" window. If you don't see this window You must do Window->Show view->Make Target. Thus you can create libfoo.so file using Eclipse when double-clicked on the "all" rule in the "Make target" view.
At this moment You can create PyDev project with foo.py file. If you don't know about PyDev you must go to this site. It is Eclipse plugin for python language. When you will have installed this plugin You will can to work with your python file under the Eclipse.
See some images.

Compile c++ Programm with CMake that uses Boost/python.hpp

I'm currently trying to compile a c++ file using CMake.
But since I'm using Boost::python it won't compile.
I set up a little test file to figure out what I need to do but I just can't get it to work.
Any Help would be greatly appreciated!!
The test file:
#include <Python.h>
#include <boost/python.hpp>
#include <iostream>
using std::cout;
using std::endl;
int main()
{
namespace py = boost::python;
Py_Initialize();
// Retrieve the main module's namespace
py::object global(py::import("__main__").attr("__dict__"));
py::exec("print 'Hello from Python!' \n", global, global);
return 0;
}
It will compile if I just use,
clang++ -I/usr/include/python2.7 -lpython2.7 -lboost_python -std=c++11 boosttest.cpp -o boosttest
I tried this CMakeLists.txt to get it to work.
cmake_minimum_required(VERSION 3.2)
FIND_PACKAGE(PythonLibs)
FIND_PACKAGE(Boost)
INCLUDE_DIRECTORIES(${Boost_INCLUDE_DIRS} ${PYTHON_INCLUDE_DIRS})
LINK_LIBRARIES(${Boost_LIBRARIES} ${PYTHON_LIBRARIES})
add_executable(Test1 boosttest.cpp)
target_link_libraries(Test1 ${Boost_LIBRARIES} ${PYTHON_LIBRARIES})
and what I get is
undefined reference to `boost::python::import(boost::python::str)'
and a couple more of the same category.

Thanks for your help Mark, thanks to the new errors after I included
find_package(Boost REQUIRED python)
I was able to figure out that the problem was that CMake selected the libs for python 3.4 but Boost was build against 2.7.
So the Solution was to include the version as so:
FIND_PACKAGE(PythonLibs 2.7 REQUIRED)

Did you try
find_package(Boost REQUIRED python)
also run with verbosity to see what is going on
cmake . --debug-output
make VERBOSE=1