minor changes

Author: Robbie Muir

doc/release_notes.rst

@@ -3,6 +3,7 @@ Release Notes
 
 .. Upcoming Version
 
+* Fix warning when multiplying variables with pd.Series containing time-zone aware index
 * Fix compatibility for xpress versions below 9.6 (regression)
 * Performance: Up to 50x faster ``repr()`` for variables/constraints via O(log n) label lookup and direct numpy indexing
 * Performance: Up to 46x faster ``ncons`` property by replacing ``.flat.labels.unique()`` with direct counting

linopy/common.py

@@ -18,6 +18,7 @@
 import numpy as np
 import pandas as pd
 import polars as pl
+import xarray as xr
 from numpy import arange, signedinteger
 from xarray import DataArray, Dataset, apply_ufunc, broadcast
 from xarray import align as xr_align
@@ -124,6 +125,17 @@ def get_from_iterable(lst: DimsLike | None, index: int) -> Any | None:
     return lst[index] if 0 <= index < len(lst) else None
 
 
+def try_to_convert_to_pd_datetime_index(
+    coord: xr.DataArray | Sequence | pd.Index | Any,
+) -> pd.DatetimeIndex | xr.DataArray | Sequence | pd.Index | Any:
+    try:
+        if isinstance(coord, xr.DataArray):
+            return coord.to_index()
+        return pd.DatetimeIndex(coord)  # type: ignore
+    except Exception:
+        return coord
+
+
 def pandas_to_dataarray(
     arr: pd.DataFrame | pd.Series,
     coords: CoordsLike | None = None,
@@ -164,7 +176,10 @@ def pandas_to_dataarray(
         shared_dims = set(pandas_coords.keys()) & set(coords.keys())
         non_aligned = []
         for dim in shared_dims:
+            pd_coord = pandas_coords[dim]
             coord = coords[dim]
+            if isinstance(pd_coord, pd.DatetimeIndex):
+                coord = try_to_convert_to_pd_datetime_index(coord)
             if not isinstance(coord, pd.Index):
                 coord = pd.Index(coord)
             if not pandas_coords[dim].equals(coord):

test/test_constraint.py

@@ -12,7 +12,6 @@
 import polars as pl
 import pytest
 import xarray as xr
-import xarray.core
 from xarray.testing import assert_equal
 
 import linopy

test/test_variables.py

@@ -3,6 +3,9 @@
 This module aims at testing the correct behavior of the Variables class.
 """
 
+import warnings
+from datetime import UTC, datetime
+
 import numpy as np
 import pandas as pd
 import pytest
@@ -122,3 +125,23 @@ def test_scalar_variable(m: Model) -> None:
     x = ScalarVariable(label=0, model=m)
     assert isinstance(x, ScalarVariable)
     assert x.__rmul__(x) is NotImplemented  # type: ignore
+
+
+def test_timezone_alignment_with_multiplication() -> None:
+    utc_index = pd.date_range(
+        start=datetime(2025, 1, 1),
+        freq="15min",
+        periods=4,
+        tz=UTC,
+        name="time",
+    )
+    model = Model()
+    series1 = pd.Series(index=utc_index, data=1.0)
+    var1 = model.add_variables(coords=[utc_index], name="var1")
+
+    with warnings.catch_warnings():
+        warnings.simplefilter("error")
+        expr = var1 * series1
+    index: pd.DatetimeIndex = expr.coords["time"].to_index()  # type: ignore
+    assert index.equals(utc_index)
+    assert index.tzinfo is UTC