--- a/python/moving.py	Sun Oct 18 22:32:46 2009 -0400
+++ b/python/moving.py	Mon Oct 19 13:16:21 2009 -0400
@@ -6,3 +6,88 @@
 __metaclass__ = type
 
 #class MovingObject:
+
+class TimeInterval:
+    '''Temporal interval'''
+    def __init__(self, first=0, last=-1):
+        self.first=first
+        self.last=last
+
+    def __str__(self):
+        return '%d %d'%(self.first, self.last)
+
+    def empty(self):
+        '''
+        >>> TimeInterval().empty()
+        True
+        >>> TimeInterval(0,1).empty()
+        False
+        '''
+        return self.first > self.last
+
+    def length(self):
+        '''Returns the length of the interval
+        
+        >>> TimeInterval(0,1).length()
+        2
+        >>> TimeInterval(10,8).length()
+        0
+        '''
+        return max(0,self.last-self.first+1)
+
+    def getList(self):
+        return [self.first, self.last]
+
+    def contains(self, instant):
+        return (self.first<=instant and self.last>=instant)
+
+    def inside(self, interval2):
+        'indicates if the temporal interval of self is comprised in interval2'
+        return (self.first >= interval2.first) and (self.last <= interval2.last)
+
+    def union(self, interval2):
+        '''Largest interval comprising self and interval2'''
+        return TimeInterval(min(self.first, interval2.first), max(self.last, interval2.last))
+        
+    def intersection(self, interval2):
+        '''Largest interval comprising self and interval2'''
+        return TimeInterval(max(self.first, interval2.first), min(self.last, interval2.last))
+
+class STObject:
+    '''Class for spatio-temporal object
+    i.e. with temporal and spatial existence 
+    (time interval and bounding polygon for positions (e.g. rectangle)'''
+
+    def __init__(self, timeInterval = TimeInterval(), boundingPolygon = None, num = None):
+        self.timeInterval = timeInterval
+        self.boundingPolygon = boundingPolygon
+        self.num = num
+
+    def empty(self):
+        return self.timeInterval.empty()
+
+    def getFirstInstant(self):
+        return self.timeInterval.first()
+
+    def getLastInstant(self):
+        return self.timeInterval.first()
+
+    
+        
+# return bounding box, and generic polygon, that defaults to box
+
+class Track(STObject):
+    '''Class for trajectories
+    i.e. sequence of positions'''
+    pass
+
+
+
+if __name__ == "__main__":
+    import doctest
+    import unittest
+    #suite = doctest.DocFileSuite('tests/ubc_utils.txt')
+    suite = doctest.DocTestSuite()
+    unittest.TextTestRunner().run(suite)
+    #doctest.testmod()
+    #doctest.testfile("example.txt")

--- a/python/utils.py	Sun Oct 18 22:32:46 2009 -0400
+++ b/python/utils.py	Mon Oct 19 13:16:21 2009 -0400
@@ -59,5 +59,8 @@
 
 if __name__ == "__main__":
     import doctest
-    doctest.testmod()
+    import unittest
+    suite = doctest.DocFileSuite('tests/ubc_utils.txt')
+    unittest.TextTestRunner().run(suite)
+    #doctest.testmod()
     #doctest.testfile("example.txt")