--- a/trafficintelligence/utils.py	Fri Jul 20 13:50:43 2018 -0400
+++ b/trafficintelligence/utils.py	Fri Jul 20 14:03:34 2018 -0400
@@ -342,6 +342,10 @@
 def timeToFrames(t, frameRate):
     return frameRate*(t.hour*3600+t.minute*60+t.second)
 
+def timeModulo(t, duration):
+    'returns the time modulo the duration in min'
+    return time(t.hour, t.minute//duration, t.second)
+
 def sortXY(X,Y):
     'returns the sorted (x, Y(x)) sorted on X'
     D = {}
@@ -591,6 +595,19 @@
         print('Unknown aggregation method: {}'.format(funcStr))
         return None
 
+def aggregationMethods(methods, centiles = None):
+    aggFunctions = {}
+    headers = []
+    for method in methods:
+        if method == 'centile':
+            aggFunctions[method] = aggregationFunction(method, centiles)
+            for c in centiles:
+                headers.append('{}{}'.format(method,c))
+        else:
+            aggFunctions[method] = aggregationFunction(method)
+            headers.append(method)
+    return aggFunctions, headers
+    
 #########################
 # regression analysis using statsmodels (and pandas)
 #########################