Function PyArray_FromFile

numpy/core/src/multiarray/ctors.c:3496–3558

NUMPY_API * * Given a ``FILE *`` pointer ``fp``, and a ``PyArray_Descr``, return an * array corresponding to the data encoded in that file. * * The reference to `dtype` is stolen (it is possible that the passed in * dtype is not held on to). * * The number of elements to read is given as ``num``; if it is < 0, then * then as many as possible are read. * * If ``sep`` is NULL or empty, th

 * necessary is read by this routine.
 */
NPY_NO_EXPORT PyObject *
PyArray_FromFile(FILE *fp, PyArray_Descr *dtype, npy_intp num, char *sep)
{
    PyArrayObject *ret;
    size_t nread = 0;

    if (dtype == NULL) {
        return NULL;
    }

    if (PyDataType_REFCHK(dtype)) {
        PyErr_SetString(PyExc_ValueError,
                "Cannot read into object array");
        Py_DECREF(dtype);
        return NULL;
    }
    if (dtype->elsize == 0) {
        /* Nothing to read, just create an empty array of the requested type */
        return PyArray_NewFromDescr_int(
                &PyArray_Type, dtype,
                1, &num, NULL, NULL,
                0, NULL, NULL,
                _NPY_ARRAY_ALLOW_EMPTY_STRING);
    }
    if ((sep == NULL) || (strlen(sep) == 0)) {
        ret = array_fromfile_binary(fp, dtype, num, &nread);
    }
    else {
        if (dtype->f->scanfunc == NULL) {
            PyErr_SetString(PyExc_ValueError,
                    "Unable to read character files of that array type");
            Py_DECREF(dtype);
            return NULL;
        }
        ret = array_from_text(dtype, num, sep, &nread, fp,
                (next_element) fromfile_next_element,
                (skip_separator) fromfile_skip_separator, NULL);
    }
    if (ret == NULL) {
        Py_DECREF(dtype);
        return NULL;
    }
    if (((npy_intp) nread) < num) {
        /*
         * Realloc memory for smaller number of elements, use original dtype
         * which may have include a subarray (and is used for `nread`).
         */
        const size_t nsize = PyArray_MAX(nread,1) * dtype->elsize;
        char *tmp;

        /* The handler is always valid */
        if((tmp = PyDataMem_UserRENEW(PyArray_DATA(ret), nsize,
                                     PyArray_HANDLER(ret))) == NULL) {
            Py_DECREF(dtype);
            Py_DECREF(ret);
            return PyErr_NoMemory();
        }
        ((PyArrayObject_fields *)ret)->data = tmp;