TimeseriesUtility.pad_and_trim_trace trim fix

Applied the same fix to the trim logic in method
TimeseriesUtility.pad_and_trim_trace() as previously applied
to the pad logic. Added a unit test that would have failed
using the old logic.

geomagio/TimeseriesUtility.py

@@ -507,7 +507,7 @@ def pad_and_trim_trace(trace, starttime, endtime):
     trace_delta = trace.stats.delta
     if trace_starttime < starttime:
         # trim to starttime
-        cnt = int(math.ceil((starttime - trace_starttime) / trace_delta))
+        cnt = int(math.ceil(round((starttime - trace_starttime) / trace_delta, 6)))
         if cnt > 0:
             trace.data = trace.data[cnt:]
             trace_starttime = trace_starttime + trace_delta * cnt
@@ -515,6 +515,7 @@ def pad_and_trim_trace(trace, starttime, endtime):
     elif trace_starttime > starttime:
         # pad to starttime
         cnt = int(round((trace_starttime - starttime) / trace_delta, 6))
+        # cnt = int((trace_starttime - starttime) / trace_delta)
         if cnt > 0:
             trace.data = numpy.concatenate(
                 [numpy.full(cnt, numpy.nan, dtype=numpy.float64), trace.data]
@@ -523,12 +524,13 @@ def pad_and_trim_trace(trace, starttime, endtime):
             trace.stats.starttime = trace_starttime
     if trace_endtime > endtime:
         # trim to endtime, at least 1 sample to remove
-        cnt = int(math.ceil((trace_endtime - endtime) / trace_delta))
+        cnt = int(math.ceil(round((trace_endtime - endtime) / trace_delta, 6)))
         trace.data = trace.data[:-cnt]
         trace.stats.npts = len(trace.data)
     elif trace_endtime < endtime:
         # pad to endtime
         cnt = int(round((endtime - trace_endtime) / trace.stats.delta, 6))
+        # cnt = int((endtime - trace_endtime) / trace.stats.delta)
         if cnt > 0:
             trace.data = numpy.concatenate(
                 [trace.data, numpy.full(cnt, numpy.nan, dtype=numpy.float64)]

test/TimeseriesUtility_test.py

@@ -425,6 +425,36 @@ def test_pad_and_trim_trace():
     assert_array_equal(trace.data, [numpy.nan, 1, 2, 3, numpy.nan])
 
 
+def test_pad_and_trim_trace_fixfloat():
+    """TimeseriesUtility_test.test_pad_and_trim_trace_fixfloat()
+    This tests whether pad_and_trim_trace() handles a known
+    floating point precision trouble-maker encountered with
+    UTCDateTimes correctly.
+    """
+    trace = _create_trace(
+        numpy.linspace(1, 56, 56), "X", UTCDateTime("2020-05-28T15:53:50.7"), delta=0.1
+    )
+    assert_equal(trace.stats.starttime, UTCDateTime("2020-05-28T15:53:50.7"))
+    assert_equal(trace.stats.endtime, UTCDateTime("2020-05-28T15:53:56.2"))
+    # This should create a 70 sample trace of 10 Hz data, inclusive of the
+    # known startime and endtime. Early versions of pad_and_trim_trace() did
+    # not handle this scenario correctly, returning 68 samples, and missing
+    # both the 1st and last of the expected samples.
+    TimeseriesUtility.pad_and_trim_trace(
+        trace,
+        starttime=UTCDateTime("2020-05-28T15:53:50.0"),
+        endtime=UTCDateTime("2020-05-28T15:53:56.9"),
+    )
+    assert_equal(trace.stats.starttime, UTCDateTime("2020-05-28T15:53:50.0"))
+    assert_equal(trace.stats.endtime, UTCDateTime("2020-05-28T15:53:56.9"))
+    assert_array_equal(
+        trace.data,
+        numpy.concatenate(
+            ([numpy.nan] * 7, numpy.linspace(1, 56, 56), [numpy.nan] * 7)
+        ),
+    )
+
+
 def _create_trace(data, channel, starttime, delta=60.0):
     stats = Stats()
     stats.channel = channel