Fix: too many samples returned for ranged async data

pyDmdReader/_dmd_reader.py

@@ -353,8 +353,16 @@ def __get_ranged_sweeps(self, ch_config, start_time, end_time) -> Tuple[np.array
                             block_max_samples = last_sample - first_sample + 1
 
                         raw_timestamps, raw_values, next_sample = self.__get_single_sweep(ch_config, first_sample, block_max_samples)
-                        data = np.r_[data, raw_values]
-                        timestamps = np.r_[timestamps, raw_timestamps]
+
+                        if len(raw_timestamps) > 0:
+                            if raw_timestamps[-1] <= actual_end_time:
+                                timestamps = np.r_[timestamps, raw_timestamps]
+                                data = np.r_[data, raw_values]
+                            else:
+                                # Do not use sample values outside the requested range
+                                last_valid = np.argmax(raw_timestamps > actual_end_time)
+                                timestamps = np.r_[timestamps, raw_timestamps[:last_valid]]
+                                data = np.r_[data, raw_values[:(last_valid * ch_config.max_sample_dimension)]]
 
                         first_sample = next_sample
 

tests/test_loadfile_dataframe.py

@@ -9,6 +9,7 @@
 import pytest
 
 SIMPLE_DMD = os.path.join(os.path.dirname(__file__), "data/simple.dmd")
+SYNCASYNC_DMD = os.path.join(os.path.dirname(__file__), "data/syncasync.dmd")
 INTERNAL_DMD = 'DMD_DEMO_FILE'
 
 def test_check_invalid_name():
@@ -149,3 +150,27 @@ def test_timerange_simple():
     assert round(data.index[-1], 2) == 0.4
 
     dmd.close()
+
+def test_async():
+    dmd = DmdReader(SYNCASYNC_DMD)
+    # The file has one sweeps [0 - 0.633] but a recording offset to acquisition start
+    all_data_sync = dmd.read_dataframe(dmd.channel_names[0])
+    all_data_async = dmd.read_dataframe(dmd.channel_names[1])
+    assert len(all_data_sync) == 29315
+    assert len(all_data_async) == 293
+    assert all_data_sync.index[0] == 0
+    assert round(all_data_sync.index[-1], 3) == round(dmd.measurement_duration, 3)
+    assert round(all_data_async.index[0], 2) == 0.01 # Async average with 100 Hz
+    assert round(all_data_async.index[-1], 2) == 2.93
+
+    rng_data_sync = dmd.read_dataframe(dmd.channel_names[0], start_time=0.5, end_time=1.5)
+    rng_data_async = dmd.read_dataframe(dmd.channel_names[1], start_time=0.5, end_time=1.5)
+    assert len(rng_data_sync) == 10001
+    assert len(rng_data_async) == 101
+
+    assert round(rng_data_sync.index[0], 3) == 0.5
+    assert round(rng_data_sync.index[-1], 3) == 1.5
+    assert round(rng_data_async.index[0], 2) == 0.5
+    assert round(rng_data_async.index[-1], 2) == 1.5
+
+    dmd.close()