准备记录numpy和c++的混合编程
#include <boost/python.hpp>
#include <numpy/ndarrayobject.h>
namespace bp = boost::python;
void reference_contiguous_array(PyObject* in,
PyArrayObject* in_con,
double* ptr, int& count)
{
in_con = PyArray_GETCONTIGUOUS((PyArrayObject*)in);
ptr = (double*)PyArray_DATA(in_con);
int num_dim = PyArray_NDIM(in_con);
npy_intp* pdim = PyArray_DIMS(in_con);
count = 1;
for (int i = 0; i < num_dim; i++)
{
count *= pdim[i];
}
}
void dereference(PyObject* o)
{
Py_DECREF(o);
}
PyObject* entry_square_matrix(PyObject* input_matrix)
{
// get the input array
double* ptr;
int count;
PyArrayObject* input_contigous_array;
reference_contiguous_array(input_matrix, input_contigous_array, ptr, count); // create the output array
npy_intp dst_dim[1];
dst_dim[0] = count;
PyObject* out_matrix = PyArray_SimpleNew(1, dst_dim, NPY_FLOAT64);
double* ptr_out;
PyArrayObject* output_contigous_array;
reference_contiguous_array(out_matrix, output_contigous_array, ptr_out, count);
for (int i = 0; i < count; i++)
{
ptr_out[i] = ptr[i] * ptr[i];
}
dereference((PyObject*)input_contigous_array);
dereference((PyObject*)output_contigous_array);
return out_matrix;
}
BOOST_PYTHON_MODULE(_func)
{
import_array();
bp::def(square_matrix, entry_square_matrix);
}