--- a/trafficintelligence/events.py	Tue Jun 21 17:06:06 2022 -0400
+++ b/trafficintelligence/events.py	Tue Jun 21 17:06:21 2022 -0400
@@ -92,7 +92,7 @@
                       's',
                       's']
 
-    timeIndicators = ['Time to Collision', 'predicted Post Encroachment Time']
+    mostSevereIsMinIndicators = ['Distance', 'Time to Collision', 'predicted Post Encroachment Time']
 
     def __init__(self, num = None, timeInterval = None, roaduserNum1 = None, roaduserNum2 = None, roadUser1 = None, roadUser2 = None):
         moving.STObject.__init__(self, num, timeInterval)

--- a/trafficintelligence/moving.py	Tue Jun 21 17:06:06 2022 -0400
+++ b/trafficintelligence/moving.py	Tue Jun 21 17:06:21 2022 -0400
@@ -860,7 +860,7 @@
         cval : Value to fill past the edges of the input if mode is constant. Default is 0.0.
 
         https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.savgol_filter.html#scipy.signal.savgol_filter'''
-        if removeBothEnds >=1:
+        if nInstantsIgnoredAtEnds >=1:
             pos = [self.positions[0][nInstantsIgnoredAtEnds:-nInstantsIgnoredAtEnds],
                    self.positions[1][nInstantsIgnoredAtEnds:-nInstantsIgnoredAtEnds]]
         else:
@@ -1326,8 +1326,8 @@
         else:
             newNum = num
         commonTimeInterval = obj1.commonTimeInterval(obj2)
-        emptyInterval = TimeInterval(min(obj1.getLastInstant(),obj2.getLastInstant()), max(obj1.getFirstInstant(),obj2.getFirstInstant()))
-        if commonTimeInterval.empty() and emptyInterval.length() >= 3:
+        if commonTimeInterval.empty(): # and emptyInterval.length() >= 2: not needed 2 to include situations successive positions, but issues with missing last velocity and reloading
+            emptyInterval = TimeInterval(min(obj1.getLastInstant(),obj2.getLastInstant()), max(obj1.getFirstInstant(),obj2.getFirstInstant()))
             if newFeatureNum is None:
                 print('Not merging objects {} and {}, missing new feature number'.format(obj1.getNum(),obj2.getNum()))
                 return None, None
@@ -1564,12 +1564,17 @@
         else:
             return speeds
 
-    def getAccelerations(self, window_length, polyorder, delta=1.0, axis=-1, mode='interp', cval=0.0, speeds = None, nInstantsIgnoredAtEnds = 0):
+    def getAccelerations(self, window_length, polyorder, delta=1.0, axis=-1, mode='interp', cval=0.0, nInstantsIgnoredAtEnds = 0):
         '''Returns the 1-D acceleration from the 1-D speeds
         Caution about previously filtered data'''
-        if speeds is None:
-            speeds = self.getSpeeds(nInstantsIgnoredAtEnds)
-        return savgol_filter(speeds, window_length, polyorder, 1, delta, axis, mode, cval)
+        speeds = self.getSpeeds(nInstantsIgnoredAtEnds)
+        if window_length > len(speeds):
+            wlength = min(window_length, len(speeds))
+            if wlength % 2 == 0:
+                wlength -=1
+        else:
+            wlength = window_length
+        return savgol_filter(speeds, wlength, min(wlength-1, polyorder), 1, delta, axis, mode, cval)
 
     def getSpeedIndicator(self):
         from indicators import SeverityIndicator

--- a/trafficintelligence/storage.py	Tue Jun 21 17:06:06 2022 -0400
+++ b/trafficintelligence/storage.py	Tue Jun 21 17:06:21 2022 -0400
@@ -326,6 +326,8 @@
 
                 except sqlite3.OperationalError as error:
                     printDBError(error)
+    else:
+        print('Impossible to load from non-existing file '+filename)
     return objects
 
 def loadObjectFeatureFrameNumbers(filename, objectNumbers = None):
@@ -540,7 +542,7 @@
                         indicatorTypeNum = row[5]
                         indicatorName = events.Interaction.indicatorNames[indicatorTypeNum]
                         indicatorValues = {row[6]:row[7]}
-                        interactions[-1].indicators[indicatorName] = indicators.SeverityIndicator(indicatorName, indicatorValues, mostSevereIsMax = not indicatorName in events.Interaction.timeIndicators)
+                        interactions[-1].indicators[indicatorName] = indicators.SeverityIndicator(indicatorName, indicatorValues, mostSevereIsMax = not indicatorName in events.Interaction.mostSevereIsMinIndicators)
                     else:
                         indicatorValues[row[6]] = row[7]
                         interactions[-1].indicators[indicatorName].timeInterval.last = row[6]

--- a/trafficintelligence/tests/moving.txt	Tue Jun 21 17:06:06 2022 -0400
+++ b/trafficintelligence/tests/moving.txt	Tue Jun 21 17:06:21 2022 -0400
@@ -335,9 +335,9 @@
 >>> f12.getVelocities().length()
 5
 
->>> o14, f14 = MovingObject.concatenate(o1, o4, 16)
+>>> o14, f14 = MovingObject.concatenate(o1, o4, 16, 16)
 >>> len(o14.getFeatures())
-2
+3
 >>> o14.getPositionAtInstant(10) == o1.getPositionAtInstant(10)
 True
 >>> o14.getPositionAtInstant(11) == o4.getPositionAtInstant(11)