More skimming and test decimate with times

src/spikeinterface/preprocessing/decimate.py

@@ -99,6 +99,7 @@ def __init__(
         if parent_recording_segment.time_vector is not None:
             time_vector = parent_recording_segment.time_vector[decimation_offset::decimation_factor]
             decimated_sampling_frequency = None
+            t_start = None
         else:
             time_vector = None
             if parent_recording_segment.t_start is None:

src/spikeinterface/preprocessing/tests/test_decimate.py

@@ -11,13 +11,8 @@
 @pytest.mark.parametrize("num_segments", [1, 2])
 @pytest.mark.parametrize("decimation_offset", [0, 5, 21, 101])
 @pytest.mark.parametrize("decimation_factor", [1, 7, 50])
-@pytest.mark.parametrize("start_frame", [0, 1, 5, None, 1000])
-@pytest.mark.parametrize("end_frame", [0, 1, 5, None, 1000])
-def test_decimate(num_segments, decimation_offset, decimation_factor, start_frame, end_frame):
-    rec = generate_recording()
-
-    segment_num_samps = [101 + i for i in range(num_segments)]
-
+def test_decimate(num_segments, decimation_offset, decimation_factor):
+    segment_num_samps = [20000, 40000]
     rec = NumpyRecording([np.arange(2 * N).reshape(N, 2) for N in segment_num_samps], 1)
 
     parent_traces = [rec.get_traces(i) for i in range(num_segments)]
@@ -30,10 +25,19 @@ def test_decimate(num_segments, decimation_offset, decimation_factor, start_fram
     decimated_rec = DecimateRecording(rec, decimation_factor, decimation_offset=decimation_offset)
     decimated_parent_traces = [parent_traces[i][decimation_offset::decimation_factor] for i in range(num_segments)]
 
-    if start_frame is None:
-        start_frame = max(decimated_rec.get_num_samples(i) for i in range(num_segments))
-    if end_frame is None:
-        end_frame = max(decimated_rec.get_num_samples(i) for i in range(num_segments))
+    for start_frame in [0, 1, 5, None, 1000]:
+        for end_frame in [0, 1, 5, None, 1000]:
+            if start_frame is None:
+                start_frame = max(decimated_rec.get_num_samples(i) for i in range(num_segments))
+            if end_frame is None:
+                end_frame = max(decimated_rec.get_num_samples(i) for i in range(num_segments))
+
+            for i in range(num_segments):
+                assert decimated_rec.get_num_samples(i) == decimated_parent_traces[i].shape[0]
+                assert np.all(
+                    decimated_rec.get_traces(i, start_frame, end_frame)
+                    == decimated_parent_traces[i][start_frame:end_frame]
+                )
 
     for i in range(num_segments):
         assert decimated_rec.get_num_samples(i) == decimated_parent_traces[i].shape[0]
@@ -42,5 +46,36 @@ def test_decimate(num_segments, decimation_offset, decimation_factor, start_fram
         )
 
 
+def test_decimate_with_times():
+    rec = generate_recording(durations=[5, 10])
+
+    # test with times
+    times = [rec.get_times(0) + 10, rec.get_times(1) + 20]
+    for i, t in enumerate(times):
+        rec.set_times(t, i)
+
+    decimation_factor = 2
+    decimation_offset = 1
+    decimated_rec = DecimateRecording(rec, decimation_factor, decimation_offset=decimation_offset)
+
+    for segment_index in range(rec.get_num_segments()):
+        assert np.allclose(
+            decimated_rec.get_times(segment_index),
+            rec.get_times(segment_index)[decimation_offset::decimation_factor],
+        )
+
+    # test with t_start
+    rec = generate_recording(durations=[5, 10])
+    t_starts = [10, 20]
+    for t_start, rec_segment in zip(t_starts, rec._recording_segments):
+        rec_segment.t_start = t_start
+    decimated_rec = DecimateRecording(rec, decimation_factor, decimation_offset=decimation_offset)
+    for segment_index in range(rec.get_num_segments()):
+        assert np.allclose(
+            decimated_rec.get_times(segment_index),
+            rec.get_times(segment_index)[decimation_offset::decimation_factor],
+        )
+
+
 if __name__ == "__main__":
     test_decimate()