dimensioned export (gwy, HDF5)

backend/importers/gwy.py

@@ -20,19 +20,42 @@ def load(path: Path) -> list[DataField]:
 
     fields = []
     for ch in channels.values():
-        data = np.array(ch.data, dtype=np.float64).reshape(ch.yres, ch.xres)
+        # gwyfile.objects.GwyDataField exposes .data as an already-2D ndarray
+        # (no xres/yres attributes — those were removed in gwyfile 0.3+).
+        data = np.asarray(ch.data, dtype=np.float64)
+        if data.ndim != 2:
+            # Defensive: if a future gwyfile version yields a flat buffer, the
+            # dimensions live in the serialized object's xres/yres keys.
+            xres = int(ch.get("xres", data.size))
+            yres = int(ch.get("yres", 1))
+            data = data.reshape(yres, xres)
         fields.append(DataField(
             data=data,
             xreal=float(ch.xreal),
             yreal=float(ch.yreal),
             xoff=float(getattr(ch, "xoff", 0.0)),
             yoff=float(getattr(ch, "yoff", 0.0)),
-            si_unit_xy="m",
-            si_unit_z="m",
+            si_unit_xy=_unit_str(getattr(ch, "si_unit_xy", None)) or "m",
+            si_unit_z=_unit_str(getattr(ch, "si_unit_z", None)) or "m",
         ))
     return fields
 
 
+def _unit_str(si_unit: object) -> str:
+    """Extract the unit string from a GwySIUnit without importing gwyfile.
+
+    Loaded GwySIUnit objects behave like dicts with a ``unitstr`` key.
+    """
+    if si_unit is None:
+        return ""
+    if hasattr(si_unit, "unitstr"):
+        return str(getattr(si_unit, "unitstr") or "")
+    try:
+        return str(si_unit["unitstr"] or "")
+    except (KeyError, TypeError):
+        return ""
+
+
 def channel_names(path: Path) -> list[str]:
     import gwyfile
     try: