epoch start and stop time accept single and double precision (#885)

* epoch start and stop time accept single and double precision

* add native float

Author: ajtritt

src/pynwb/epoch.py

@@ -8,6 +8,7 @@
 from .core import DynamicTable, ElementIdentifiers
 
 import pandas as pd
+import numpy as np
 
 
 @register_class('TimeIntervals', CORE_NAMESPACE)
@@ -36,8 +37,8 @@ class TimeIntervals(DynamicTable):
     def __init__(self, **kwargs):
         call_docval_func(super(TimeIntervals, self).__init__, kwargs)
 
-    @docval({'name': 'start_time', 'type': float, 'doc': 'Start time of epoch, in seconds'},
-            {'name': 'stop_time', 'type': float, 'doc': 'Stop time of epoch, in seconds'},
+    @docval({'name': 'start_time', 'type': (float, np.float32, np.float64), 'doc': 'Start time of epoch, in seconds'},
+            {'name': 'stop_time', 'type': (float, np.float32, np.float64), 'doc': 'Stop time of epoch, in seconds'},
             {'name': 'tags', 'type': (str, list, tuple), 'doc': 'user-defined tags used throughout time intervals',
              'default': None},
             {'name': 'timeseries', 'type': (list, tuple, TimeSeries), 'doc': 'the TimeSeries this epoch applies to',