# tree_d_3d.kernels.quadtree_moments.quadtree_moments_numpy

*module*

The NumPy version of the ``quadtree_moments`` kernel, for machines without Pyccel.

Vectorized over the particles of each node; the same arguments and results as ``quadtree_moments_pyccel.py``.

[View source](https://github.com/max-models/tree-d-3d/blob/devel/src/tree_d_3d/kernels/quadtree_moments/quadtree_moments_numpy.py#L1-L1)

## tree_d_3d.kernels.quadtree_moments.quadtree_moments_numpy.quadtree_moments

*function*

```python
def quadtree_moments(pos: np.ndarray, charge: np.ndarray, perm: np.ndarray, node_count: int, node_center: np.ndarray, node_start: np.ndarray, node_end: np.ndarray, node_q: np.ndarray, node_qabs: np.ndarray, node_p: np.ndarray, node_s: np.ndarray) -> None
```

Signed moments of every node about its centre; ``node_s`` is xx, xy, yy.

[View source](https://github.com/max-models/tree-d-3d/blob/devel/src/tree_d_3d/kernels/quadtree_moments/quadtree_moments_numpy.py#L11-L36)