Remove gaps in intraday charts when the market is not open

plotting/chart.py

@@ -1,4 +1,4 @@
-from pandas import date_range, Series
+from pandas import date_range, Series, to_datetime
 from plotly.basedatatypes import BaseTraceType
 from typing import List
 
@@ -15,5 +15,16 @@ class Chart:
         start_date = self.x.min()
         end_date = self.x.max()
         all_dates = date_range(start = start_date, end = end_date)
+
         missing_dates = all_dates.difference(self.x)
-        return [dict(values = missing_dates)]
+        range_breaks = [dict(values = missing_dates)]
+
+        if self.is_intraday():
+            # Assuming US Eastern time zone.
+            range_breaks.append(dict(bounds = [16, 9.5], pattern = 'hour'))
+
+        return range_breaks
+
+    def is_intraday(self) -> bool:
+        # Check if the x-axis series has a time component other than midnight.
+        return any(to_datetime(self.x).dt.time != to_datetime(self.x).dt.normalize().dt.time)