Index: sodar/branches/scintec-branch/sodar/scintec/maindata.py
===================================================================
--- sodar/branches/scintec-branch/sodar/scintec/maindata.py (revision 267)
+++ sodar/branches/scintec-branch/sodar/scintec/maindata.py (revision 268)
@@ -166,5 +166,56 @@
                      for block
                      in blocks[2:]])
-        
+    
+    def __call__(self,timestamp,start=False):
+        """
+        Get a profile by timestamp
+        
+        maindata_instance(timestamp[,start]) -> <Profile object>
+        
+        Where:
+        
+            timestamp is a datetime.datetime object representing either
+            the start or stop timestamp of the Profile object returned.
+            
+            start is a bool object. If start is False (default), then
+            timestamp is matched to the stop timestamp of the returned
+            Profile object. Otherwise, if start is True, then timestamp is
+            matched to the start timestamp of the returned Profile object.
+        
+        Access profiles by timestamp:
+        >>> main_data = MainData(good_mnd)
+        >>> main_data(datetime(2009, 11, 17, 0, 30)).stop
+        datetime.datetime(2009, 11, 17, 0, 30)
+        >>> main_data(datetime(2009, 11, 17, 0, 0),True).start
+        datetime.datetime(2009, 11, 17, 0, 0)
+        >>> main_data(datetime(2009, 11, 18, 0, 0)).stop
+        datetime.datetime(2009, 11, 18, 0, 0)
+        >>> main_data(datetime(2009, 11, 17, 23, 0),True).start
+        datetime.datetime(2009, 11, 17, 23, 0)
+        >>> main_data(datetime(2009, 11, 16, 0, 30))
+        Traceback (most recent call last):
+            ...
+        IndexError: 'MainData' object index out of range
+        >>> main_data('OK')
+        Traceback (most recent call last):
+            ...
+        TypeError: 'MainData' object indices must be datetime.datetime
+        instances
+        """
+        
+        for profile in self:
+            if start:
+                boundary = profile.start
+            else:
+                boundary = profile.stop
+            if boundary == timestamp:
+                return profile
+        if isinstance(timestamp,datetime):
+            raise IndexError, ' '.join([repr(self.__class__.__name__),
+                                        'object index out of range',])
+        else:
+            raise TypeError, ' '.join([repr(self.__class__.__name__),
+                                       'object indices must be',
+                                       'datetime.datetime instances',])
 
 class Profile(list):
@@ -188,5 +239,5 @@
     ['z', 'speed', 'dir', 'W', 'sigW', 'bck', 'error']
     
-    Access profiles by sequence number and variables by attribute name:
+    Access observations by sequence number and variables by attribute name:
     >>> profile[0] == {'z':'10', 'speed':'99.99', 'dir':'999.9',
     ...                'W':'-0.05', 'sigW':'0.40', 'bck':'5.46E+03',
@@ -202,5 +253,5 @@
     '99.99'
     
-    Access profiles by elevation and variables by attribute name:
+    Access observations by elevation and variables by attribute name:
     >>> profile['10'] == {'z':'10', 'speed':'99.99', 'dir':'999.9',
     ...                   'W':'-0.05', 'sigW':'0.40', 'bck':'5.46E+03',
@@ -241,5 +292,5 @@
         ['z', 'speed', 'dir', 'W', 'sigW', 'bck', 'error']
         
-        Access profiles by sequence number and variables by attribute name:
+        Access observations by sequence number and variables by attribute name:
         >>> profile[0] == {'z':'10', 'speed':'99.99', 'dir':'999.9',
         ...                'W':'-0.05', 'sigW':'0.40', 'bck':'5.46E+03',
@@ -292,5 +343,5 @@
     def __getitem__(self,key):
         """
-        Get a profile by elevation.
+        Get a observation by elevation.
         
         profile_instance[elevation] -> <Observation object>
@@ -301,5 +352,5 @@
             (value keyed by 'z') of the Observation object.
         
-        Access profiles by elevation and variables by attribute name:
+        Access observations by elevation and variables by attribute name:
         >>> profile = Profile(good_profile)
         >>> profile['10'] == {'z':'10', 'speed':'99.99', 'dir':'999.9',
@@ -315,4 +366,12 @@
         >>> profile['200'].W
         '-0.07'
+        >>> profile[100000]
+        Traceback (most recent call last):
+            ...
+        IndexError: list index out of range
+        >>> profile['100000']
+        Traceback (most recent call last):
+            ...
+        TypeError: list indices must be integers
         """
         
@@ -625,5 +684,4 @@
             ...
         TypeError: 'Profile' instance's items are read-only
-        
         
         Without affecting the observations: