numpy array C api

Question

I have a C++ function returning a std::vector and I want to use it in python, so I\'m using the C numpy api:

static PyObject *
py_integrate(PyObject *self, P         


        

Answer 1

You will need to make a copy of the vector, since the vector will go out of scope and the memory will no longer be usable by the time you need it in Python (as stated by kwatford).

One way to make the Numpy array you need (by copying the data) is:

PyObject *out = nullptr;

std::vector *vector = new std::vector();
vector->push_back(1.);

npy_intp size = {vector.size()};

out = PyArray_SimpleNew(1, &size, NPY_DOUBLE);

memcpy(PyArray_DATA((PyArrayObject *) out), vector.data(), vector.size());