Question

I have a C++ program that keeps generating data. I have a python class that process these data. I want to use this python class to process the data: when each time a data point is generated, I can use this python script to process the data. But this python script must be “stateful”, i.e. it should be able to remember what it did before this data point.

One super basic example is, my C++ program just generates numbers, and my python class calculates the cumulative sums of the numbers generated:

Python:

class CumSum:
    def addone(x):
        self._cumsum += x; 
        print self._cumsum;

C++

[Somehow construct a CumSum instance, say c] 

for (int i=0; i<100000; i++) {
   int x = rand() % 1000; 
   [Call c.addone(x)]
}

I heard boost::python is a good way to handle this. Can anyone sketch out how to do it? I tried to read boost documents but they were too huge for me to digest.

I appreciate your help.

Answer 1

For basic information about how to execute your python script:

http://www.boost.org/doc/libs/1_47_0/libs/python/doc/tutorial/doc/html/python/embedding.html

For details on manipulating python objects in C++

http://www.boost.org/doc/libs/1_47_0/libs/python/doc/tutorial/doc/html/python/object.html

Much of boost-python is concerned with exporting your C++ classes to python but you aren’t doing that so you can ignore it.

You may be better off using a simpler wrapper like SCXX

http://davidf.sjsoft.com/mirrors/mcmillan-inc/scxx.html