snapshot...

modules/aeolus/datasource.py

@@ -110,9 +110,17 @@ class Files:
         self._current_index = 0
 
     def get_datetime(self, pathname):
+        """
+        :param pathname: The full-path of the file.
+        :return: The file's time label as a datetime object.
+        """
         pass
 
     def get_file_containing_time(self, timestamp):
+        """
+        :param timestamp: seconds since the epoch
+        :return: the file whose time range (defined as the difference between consecutive file time labels) contains timestamp.
+        """
         k = -1
         for i in range(self.ftimes.shape[0]):
             if (timestamp >= self.ftimes[i, 0]) and (timestamp < self.ftimes[i, 1]):
@@ -124,6 +132,11 @@ class Files:
         return self.flist[k], self.ftimes[k, 0], k
 
     def get_file(self, timestamp, window=None):
+        """
+        :param timestamp: seconds since the epoch.
+        :param window: the duration of files in this object. Defaults to the constructor time span.
+        :return: the file whose duration contains the timestamp.
+        """
         if window is None:
             window = self.span_seconds
         else:
@@ -135,6 +148,22 @@ class Files:
         else:
             return None, None, None
 
+    def get_file_in_range(self, timestamp, t_lo_minutes, t_hi_minutes):
+        """
+        :param timestamp:
+        :param t_lo_minutes: can be negative or positive
+        :param t_hi_minutes: can be negative or positive, but must be greater than t_lo_minutes.
+        :return: the file whose time label is within the absolute range (timestamp + t_lo_minutes, timestamp + t_hi_minutes)
+        """
+
+        t_lo = timestamp + datetime.timedelta(minutes=t_lo_minutes).seconds
+        t_hi = timestamp + datetime.timedelta(minutes=t_hi_minutes).seconds
+
+        midx = np.where(np.logical_and(self.ftimes[:, 0] >= t_lo, self.ftimes[:, 0] < t_hi))[0]
+        midx = midx[0]  # the first occurrence
+
+        return self.flist[midx], self.ftimes[midx, 0], midx
+
     def get_parameters(self):
         pass