Channels have units

CHANGELOG.md

@@ -7,6 +7,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/).
 
 ### Fixed
 - fixed bug where numpy>2.4 broke `data.join`
+- fixed bug which prevented channels from having units
 
 ### Changed
 - per [PEP 765](https://peps.python.org/pep-0765/), `return` is removed from `finally` blocks

WrightTools/data/_channel.py

@@ -61,7 +61,8 @@ def __init__(
         super().__init__(id)
         self.label = label
         self.label_seed = label_seed
-        self.units = units
+        if units is not None:
+            self.units = units
         self.dimensionality = len(self.shape)
         # attrs
         if self._parent.file.mode is not None and self._parent.file.mode != "r":

tests/data/channel/units.py

@@ -0,0 +1,17 @@
+"""Tests to do with null."""
+
+# --- import --------------------------------------------------------------------------------------
+
+
+import WrightTools as wt
+import numpy as np
+
+
+def test_assignment():
+    d = wt.Data()
+    d.create_channel("x", values=np.arange(5), units="Hz")
+    assert d["x"].units == "Hz"
+
+
+if __name__ == "__main__":
+    test_assignment()