Fix loading and IntervalSet from NWB file with metadata

pynapple/core/interval_set.py

@@ -197,6 +197,15 @@ def __init__(
             ), """
                 DataFrame must contain columns name "start" and "end" for start and end times.                   
                 """
+            # try sorting the DataFrame by start times, preserving its end pair, as an effort to preserve metadata
+            # since metadata would be dropped if starts and ends are sorted separately
+            # note that if end times are still not sorted, metadata will be dropped
+            if np.any(start["start"].diff() < 0):
+                warnings.warn(
+                    "DataFrame is not sorted by start times. Sorting it.", stacklevel=2
+                )
+                start = start.sort_values("start").reset_index(drop=True)
+
             metadata = start.drop(columns=["start", "end"])
             end = start["end"].values.astype(np.float64)
             start = start["start"].values.astype(np.float64)

pynapple/io/interface_nwb.py

@@ -85,10 +85,9 @@ def _make_interval_set(obj, **kwargs):
         df = obj.to_dataframe()
 
         if hasattr(df, "start_time") and hasattr(df, "stop_time"):
-            data = nap.IntervalSet(start=df["start_time"], end=df["stop_time"])
-            if df.shape[1] > 2:
-                metadata = df.drop(columns=["start_time", "stop_time"])
-                data.set_info(metadata)
+            df = df.rename(columns={"start_time": "start", "stop_time": "end"})
+            # create from full dataframe to ensure that metadata is associated correctly
+            data = nap.IntervalSet(df)
             return data
 
     else:

tests/test_decoding.py

@@ -7,11 +7,12 @@
 
 """Tests of decoding for `pynapple` package."""
 
-import pynapple as nap
 import numpy as np
 import pandas as pd
 import pytest
 
+import pynapple as nap
+
 
 def get_testing_set_1d():
     feature = nap.Tsd(t=np.arange(0, 100, 1), d=np.repeat(np.arange(0, 2), 50))
@@ -36,9 +37,10 @@ def test_decode_1d():
     tmp[0:50, 1] = 0.0
     np.testing.assert_array_almost_equal(proba.values, tmp)
 
+
 def test_decode_1d_with_TsdFrame():
     feature, group, tc, ep = get_testing_set_1d()
-    count = group.count(bin_size=1, ep = ep)
+    count = group.count(bin_size=1, ep=ep)
     decoded, proba = nap.decode_1d(tc, count, ep, bin_size=1)
     assert isinstance(decoded, nap.Tsd)
     assert isinstance(proba, nap.TsdFrame)
@@ -50,6 +52,7 @@ def test_decode_1d_with_TsdFrame():
     tmp[0:50, 1] = 0.0
     np.testing.assert_array_almost_equal(proba.values, tmp)
 
+
 def test_decode_1d_with_feature():
     feature, group, tc, ep = get_testing_set_1d()
     decoded, proba = nap.decode_1d(tc, group, ep, bin_size=1, feature=feature)
@@ -63,7 +66,8 @@ def test_decode_1d_with_feature():
     tmp[50:, 0] = 0.0
     tmp[0:50, 1] = 0.0
     np.testing.assert_array_almost_equal(proba.values, tmp)
-
+
+
 def test_decode_1d_with_dict():
     feature, group, tc, ep = get_testing_set_1d()
     group = dict(group)
@@ -79,18 +83,21 @@ def test_decode_1d_with_dict():
     tmp[0:50, 1] = 0.0
     np.testing.assert_array_almost_equal(proba.values, tmp)
 
+
 def test_decode_1d_with_wrong_feature():
     feature, group, tc, ep = get_testing_set_1d()
     with pytest.raises(RuntimeError) as e_info:
-        nap.decode_1d(tc, group, ep, bin_size=1, feature=[1,2,3])
+        nap.decode_1d(tc, group, ep, bin_size=1, feature=[1, 2, 3])
     assert str(e_info.value) == "Unknown format for feature in decode_1d"
 
+
 def test_decode_1d_with_time_units():
     feature, group, tc, ep = get_testing_set_1d()
     for t, tu in zip([1, 1e3, 1e6], ["s", "ms", "us"]):
         decoded, proba = nap.decode_1d(tc, group, ep, 1.0 * t, time_units=tu)
         np.testing.assert_array_almost_equal(feature.values, decoded.values)
 
+
 def test_decoded_1d_raise_errors():
     feature, group, tc, ep = get_testing_set_1d()
     with pytest.raises(Exception) as e_info:
@@ -150,9 +157,10 @@ def test_decode_2d():
     tmp[51:100:2, 1] = 1
     np.testing.assert_array_almost_equal(proba[:, :, 1], tmp)
 
+
 def test_decode_2d_with_TsdFrame():
     features, group, tc, ep, xy = get_testing_set_2d()
-    count = group.count(bin_size=1, ep = ep)
+    count = group.count(bin_size=1, ep=ep)
     decoded, proba = nap.decode_2d(tc, count, ep, 1, xy)
 
     assert isinstance(decoded, nap.TsdFrame)
@@ -169,7 +177,8 @@ def test_decode_2d_with_TsdFrame():
     tmp[1:50:2, 0] = 1
     tmp[51:100:2, 1] = 1
     np.testing.assert_array_almost_equal(proba[:, :, 1], tmp)
-
+
+
 def test_decode_2d_with_dict():
     features, group, tc, ep, xy = get_testing_set_2d()
     group = dict(group)
@@ -190,6 +199,7 @@ def test_decode_2d_with_dict():
     tmp[51:100:2, 1] = 1
     np.testing.assert_array_almost_equal(proba[:, :, 1], tmp)
 
+
 def test_decode_2d_with_feature():
     features, group, tc, ep, xy = get_testing_set_2d()
     decoded, proba = nap.decode_2d(tc, group, ep, 1, xy)

tests/test_metadata.py

@@ -111,6 +111,44 @@ def test_create_iset_from_df_with_metadata():
     np.testing.assert_array_almost_equal(df.end.values, ep.end)
 
 
+@pytest.mark.parametrize(
+    "df, expected",
+    [
+        # dataframe is sorted and metadata is kept
+        (
+            pd.DataFrame(
+                {
+                    "start": [25.0, 0.0, 10.0, 16.0],
+                    "end": [40.0, 5.0, 15.0, 20.0],
+                    "label": np.arange(4),
+                }
+            ),
+            ["DataFrame is not sorted by start times"],
+        ),
+        (
+            # dataframe is sorted and and metadata is dropped
+            pd.DataFrame(
+                {
+                    "start": [25, 0, 10, 16],
+                    "end": [40, 20, 15, 20],
+                    "label": np.arange(4),
+                }
+            ),
+            ["DataFrame is not sorted by start times", "dropping metadata"],
+        ),
+    ],
+)
+def test_create_iset_from_df_with_metadata_sort(df, expected):
+    with warnings.catch_warnings(record=True) as w:
+        ep = nap.IntervalSet(df)
+    for e in expected:
+        assert np.any([e in str(w.message) for w in w])
+    if "dropping metadata" not in expected:
+        pd.testing.assert_frame_equal(
+            ep.as_dataframe(), df.sort_values("start").reset_index(drop=True)
+        )
+
+
 @pytest.mark.parametrize(
     "index",
     [