Function array_assign_item

numpy/core/src/multiarray/mapping.c:1721–1771

* Python C-Api level item assignment (implementation for PySequence_SetItem) * * Negative indices are not accepted because PySequence_SetItem converts * them to positive indices before calling this. */

 * them to positive indices before calling this.
 */
NPY_NO_EXPORT int
array_assign_item(PyArrayObject *self, Py_ssize_t i, PyObject *op)
{
    npy_index_info indices[2];

    if (op == NULL) {
        PyErr_SetString(PyExc_ValueError,
                        "cannot delete array elements");
        return -1;
    }
    if (PyArray_FailUnlessWriteable(self, "assignment destination") < 0) {
        return -1;
    }
    if (PyArray_NDIM(self) == 0) {
        PyErr_SetString(PyExc_IndexError,
                        "too many indices for array");
        return -1;
    }

    if (i < 0) {
        /* This is an error, but undo PySequence_SetItem fix for message */
        i -= PyArray_DIM(self, 0);
    }

    indices[0].value = i;
    indices[0].type = HAS_INTEGER;
    if (PyArray_NDIM(self) == 1) {
        char *item;
        if (get_item_pointer(self, &item, indices, 1) < 0) {
            return -1;
        }
        if (PyArray_Pack(PyArray_DESCR(self), item, op) < 0) {
            return -1;
        }
    }
    else {
        PyArrayObject *view;

        indices[1].value = PyArray_NDIM(self) - 1;
        indices[1].type = HAS_ELLIPSIS;
        if (get_view_from_index(self, &view, indices, 2, 0) < 0) {
            return -1;
        }
        if (PyArray_CopyObject(view, op) < 0) {
            Py_DECREF(view);
            return -1;
        }
        Py_DECREF(view);
    }
    return 0;
}


/*