Python-сообщество

static PyObject *sum_cmd(PyObject *self, PyListObject *mass){
    Py_ssize_t  n=0;
    n=PyList_Size((PyObject*)mass);
    return Py_BuildValue("i",n);
}

>>> import mymod
>>> mymod.sum([1,2,3,4,5])
-1

double sum_cmd(PyObject *mass){
    int  i, n=0;
    double x,res = 0.0;
    PyObject *item;
    n=PyList_Size(mass);
    for(i=0;i<n;++i){
        item=PyList_GetItem(mass,i);
        PyArg_ParseTuple(item,"d",&x);
        res+=x;
    }
    return res;
}

a=numpy.zeros(5)
myfunction(a.ctypes.data,5)

def matrix(bRow, bCol, out=None):
    for i in range(len(bRow)):
        for j in range(len(bCol)):
            out[i][j]=funct(bRow[i],bCol[j])

[[[-0.240688 -0.03071  -1.119206]
  [-0.366261 -0.090405 -1.130639]
  [-0.320687  0.028917 -1.221789]]

 [[-0.366261 -0.090405 -1.130639]
  [-0.240688 -0.03071  -1.119206]
  [-0.290936 -0.141951 -1.018888]]

 [[-0.169737 -0.077079 -1.003905]
  [-0.290936 -0.141951 -1.018888]
  [-0.240688 -0.03071  -1.119206]]

 ...,

void matrix(const double & bRow[][][],const double & bCol[][][],double  & out[][]){
// обращение к элементу bCol[i][j][k]
}

void matrix(const double & bRow[],const double & bCol[], double  & out[]){
// обращение к элементу bCol[N*i+M*j+k]
}

[array([[-2.103271,  0.676978,  0.793785],
       [-1.95313 ,  0.676978,  0.681567],
       [-1.95313 ,  0.594438,  0.793785]]), array([[-1.95313 ,  0.594438,  0.793785],
       [-1.95313 ,  0.451738,  1.193785],
       [-2.35313 ,  0.662126,  1.193785],
       [-2.35313 ,  0.676978,  1.158403]]),
...

std::vector<std::vector<double> > out(n,std::vector<double>(n));

std::vector<std::vector<std::vector<double> > >bRow

$ cat test.c 
#include <vector>

extern int myfill(std::vector<double> & x){
     size_t n = x.size();
     for(int i=0; i<n; ++i){
          x[i]=i;
     }
     return 0;
}

$ cat test.py 
#!/usr/bin/python

import numpy as N
import ctypes as C
_foo = N.ctypeslib.load_library('test', '.')
from numpy.ctypeslib import ndpointer
#_foo.myfill.argtype=ndpointer(ndim=1)
#vect=N.zeros(5,ndpointer(ndim=1))
vect=N.zeros(10)
_foo.myfill(vect.ctypes.data)
#_foo.myfill(x.ctypes.data_as(ndpointer(ndim=1)))
print vect

$ c++ -fPIC -shared test.c -o test.so

$ ./test.py
Traceback (most recent call last):
  File "./test.py", line 10, in <module>
    _foo.myfill(vect.ctypes.data)
  File "/usr/lib/python2.7/ctypes/__init__.py", line 366, in __getattr__
    func = self.__getitem__(name)
  File "/usr/lib/python2.7/ctypes/__init__.py", line 371, in __getitem__
    func = self._FuncPtr((name_or_ordinal, self))
AttributeError: /media/disk/call-c/test/test.so: undefined symbol: myfill

void cCommonTensorProduct(const double* arg1,const int* shape1,int ndim1,const double* arg2,const int* shape2,int ndim2,double* result,void (*f)(double,double))
{
 int index1[10],index2[10]
 level=0
 beg:
 for(index1[level]=0;index1[level]<shape1[level];++index1[level])
 {
  if(level<ndim1) {++level;goto beg;}
  for(;;)
 {
   ....
   result[i]=f(arg1[i],arg2[k]);
   ....
 }
  end:;
 }
if(level!=0) {--level;goto end;}
 
}

def CommonTensorProduct(arg1,arg2,f):
    shape1=nd.array(arg1.shape,dtype='i')
    shape2=nd.array(arg2.shape,dtype='i')
    res=nd.zeros(arg1.shape+arg2.shape,dtype='d')
    # надо еще проверить dtype для arg1,arg2 и если не подходит - преобразовать
    cCommonTensorProduct(arg1.ctypes.data,shape1.ctypes.data,len(arg1.shape),arg2.ctypes.data,shape2.ctypes.data,len(arg2.shape),res.ctypes.data,f)