Refactor TOD base class to not provide implementations for internal m…

…ethods. Split that functionality out into a TODCache class. Also add position and velocity methods to the TOD API. Closes #28 and #32.

tests/test_tod.py

@@ -31,7 +31,7 @@ def setUp(self):
         self.mynsamp = 10
         self.myoff = self.mynsamp * self.comm.rank
         self.totsamp = self.mynsamp * self.comm.size
-        self.tod = TOD(mpicomm=self.comm, timedist=True, detectors=self.dets, samples=self.totsamp)
+        self.tod = TODCache(mpicomm=self.comm, timedist=True, detectors=self.dets, samples=self.totsamp)
         self.rms = 10.0
         self.pntgvec = np.ravel(np.random.random((self.mynsamp, 4))).reshape(-1,4)
         self.pflagvec = np.random.uniform(low=0, high=1, size=self.mynsamp).astype(np.uint8, copy=True)

toast/tod/sim_tod.py

@@ -335,6 +335,25 @@ def _put_pntg(self, detector, start, data):
         return
 
 
+    def _get_position(self, start, n):
+        return np.zeros((n,3), dtype=np.float64)
+
+
+    def _put_position(self, start, pos):
+        raise RuntimeError('cannot write data to simulated position')
+        return
+
+
+    def _get_velocity(self, start, n):
+        return np.zeros((n,3), dtype=np.float64)
+
+
+    def _put_velocity(self, start, vel):
+        raise RuntimeError('cannot write data to simulated velocity')
+        return
+
+
+
 class TODSatellite(TOD):
     """
     Provide a simple generator of satellite detector pointing.
@@ -459,3 +478,22 @@ def _put_pntg(self, detector, start, data):
         raise RuntimeError('cannot write data to simulated pointing')
         return
 
+
+    def _get_position(self, start, n):
+        return np.zeros((n,3), dtype=np.float64)
+
+
+    def _put_position(self, start, pos):
+        raise RuntimeError('cannot write data to simulated position')
+        return
+
+
+    def _get_velocity(self, start, n):
+        return np.zeros((n,3), dtype=np.float64)
+
+
+    def _put_velocity(self, start, vel):
+        raise RuntimeError('cannot write data to simulated velocity')
+        return
+
+