Fix #961: add datetime type detection in polars.DataFrame.

future_changes.md

@@ -23,4 +23,5 @@
 - Missing outer bar annotations when specifying `scale_x_reverse()/scale_y_reverse()` [[#1058](https://github.com/JetBrains/lets-plot/issues/1058)].
 - `geom_density2d`: the doc missing some 'computed' variables [[#1062](https://github.com/JetBrains/lets-plot/issues/1062)].
 - Any way to line-wrap facet labels? [[LPK-237](https://github.com/JetBrains/lets-plot-kotlin/issues/237)].
-- Missing marginal gridlines.
+- Missing marginal gridlines.
+- DateTime is not recognised in polars.DataFrame [[#961](https://github.com/JetBrains/lets-plot/issues/961)].

python-package/lets_plot/plot/util.py

@@ -6,7 +6,7 @@
 from datetime import datetime
 from typing import Any, Tuple, Sequence, Optional, Dict
 
-from lets_plot._type_utils import is_dict_or_dataframe
+from lets_plot._type_utils import is_dict_or_dataframe, is_polars_dataframe
 from lets_plot.geo_data_internals.utils import find_geo_names
 from lets_plot.mapping import MappingMeta
 from lets_plot.plot.core import aes
@@ -94,8 +94,14 @@ def __init__(self):
  'parameters': value.parameters
  })
 
+ data_as_dict = None
  if is_dict_or_dataframe(data):
- for column_name, values in data.items():
+ data_as_dict = data
+ elif is_polars_dataframe(data):
+ data_as_dict = data.to_dict()
+
+ if data_as_dict is not None:
+ for column_name, values in data_as_dict.items():
  if isinstance(values, Iterable):
  not_empty_series = any(True for _ in values)
  if not_empty_series and all(isinstance(val, datetime) for val in values):

python-package/test/plot/test_series_annotations.py

@@ -29,6 +29,12 @@ def test_as_annotated_data_dataframe():
  assert_series_annotations(df, expected_series_annotations)
 
 
+def test_as_annotated_data_polars_dataframe():
+ from polars import DataFrame as plDataFrame
+ df = plDataFrame(data_dict)
+ assert_series_annotations(df, expected_series_annotations)
+
+
 def test_as_annotated_data_list():
  data = [dt_value]
  assert {} == get_data_meta(data)