From 3f66d04c04be90c46cbb4bdfdaa84c367582d79c Mon Sep 17 00:00:00 2001
From: vera-rubin <322284620+vera-rubin@users.noreply.github.com>
Date: Wed, 14 Oct 2026 18:52:35 +0000
Subject: [PATCH] BUG: preserve dtypes when assigning wavelet packet nodes

---
 pywt/_wavelet_packets.py |  5 ++---
 pywt/tests/test_wp.py    | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/pywt/_wavelet_packets.py b/pywt/_wavelet_packets.py
index 787df4431..60878b8a6 100644
--- a/pywt/_wavelet_packets.py
+++ b/pywt/_wavelet_packets.py
@@ -295,9 +295,8 @@ def __setitem__(self, path, data):
                 subnode[path[self.PART_LEN:]] = data
             else:
                 if isinstance(data, BaseNode):
-                    self.data = np.asarray(data.data)
-                else:
-                    self.data = np.asarray(data)
+                    data = data.data
+                self.data = np.asarray(data)
                 # convert data to nearest supported dtype
                 dtype = _check_dtype(data)
                 if self.data.dtype != dtype:
diff --git a/pywt/tests/test_wp.py b/pywt/tests/test_wp.py
index 9bcd12302..52ea8e317 100644
--- a/pywt/tests/test_wp.py
+++ b/pywt/tests/test_wp.py
@@ -4,6 +4,7 @@
 import pickle
 
 import numpy as np
+import pytest
 from numpy.testing import assert_, assert_allclose, assert_equal, assert_raises
 
 import pywt
@@ -198,6 +199,29 @@ def test_wavelet_packet_dtypes():
         assert_allclose(r, x.astype(transform_dtype), atol=1e-5, rtol=1e-5)
 
 
+@pytest.mark.parametrize('packet_class, shape, kwargs', [
+    (pywt.WaveletPacket, (2,), {}),
+    (pywt.WaveletPacket2D, (2, 2), {}),
+    (pywt.WaveletPacketND, (2, 2, 2), {'axes': (0, 1, 2)}),
+])
+@pytest.mark.parametrize('dtype', [np.float32, np.float64,
+                                   np.complex64, np.complex128])
+@pytest.mark.parametrize('mode', ['symmetric', 'periodization'])
+def test_wavelet_packet_node_assignment(packet_class, shape, kwargs, dtype, mode):
+    x = np.arange(1, np.prod(shape) + 1, dtype=dtype).reshape(shape)
+    if np.iscomplexobj(x):
+        x += 1j * (x + 1)
+    wp = packet_class(x, 'haar', mode=mode, maxlevel=1, **kwargs)
+    new_wp = packet_class(None, 'haar', mode=mode, maxlevel=1, **kwargs)
+
+    for node in wp.get_level(1):
+        new_wp[node.path] = node
+        assert_equal(new_wp[node.path].data.dtype, node.data.dtype)
+        assert_equal(new_wp[node.path].data, node.data)
+
+    assert_allclose(new_wp.reconstruct(), x, atol=1e-6, rtol=1e-6)
+
+
 def test_db3_roundtrip():
     original = np.arange(512)
     wp = pywt.WaveletPacket(data=original, wavelet='db3', mode='smooth',