update

gammapy/data/data_store.py

@@ -6,6 +6,7 @@
 from astropy.table import Table
 from astropy.units import Quantity
 from astropy.io import fits
+from astropy.utils import lazyproperty
 from .observation import ObservationTable
 from ..utils.scripts import make_path
 from ..extern.pathlib import Path
@@ -216,6 +217,26 @@ def load(self, obs_id, filetype):
         else:
             raise ValueError('Invalid filetype.')
 
+    def obs(self, obs_id):
+        """Access a given `~gammapy.data.Observation`.
+
+        Accessing data via ``obs`` is an alternative to ``load_obs``
+        that allows dot-access and tab-completion on objects,
+        using lazy lookup.
+
+
+        Parameters
+        ----------
+        obs_id : int
+            Observation ID.
+
+        Returns
+        -------
+        obs : `~gammapy.data.Observation`
+            Observation container
+        """
+        raise NotImplementedError
+
     def load_all(self, filetype):
         """Load a given file type for all observations
 
@@ -385,13 +406,20 @@ class Observation(object):
     >>> obs.info()
     TODO: prints summary output...
     """
+
     def __init__(self, events=None, gti=None, aeff=None, edisp=None, psf=None):
-        self.events = events
+        self.__dict__['events'] = events
         self.gti = gti
         self.aeff = aeff
         self.edisp = edisp
         self.psf = psf
 
+    @lazyproperty
+    def events(self):
+        # access self._datastore_info
+        # load and return
+        pass
+
     def peek(self):
         """Quick-look plots in a few panels."""
 

gammapy/scripts/background_model.py

@@ -153,8 +153,8 @@ def background_group():
     obs_table = config.obs_table.copy()
 
     # Define observation groups
-    # zenith_bins = np.array([0, 20, 30, 40, 50, 90])
-    zenith_bins = np.array([0, 49, 90])
+    zenith_bins = np.array([0, 20, 30, 40, 50, 90])
+    # zenith_bins = np.array([0, 49, 90])
     # zenith_bins = np.array([0, 30, 90])  # for testing
     axes = [ObservationGroupAxis('ZEN_PNT', zenith_bins, 'bin_edges')]
     obs_groups = ObservationGroups(axes)