# HG changeset patch
# User Nicolas Saunier <nicolas.saunier@polymtl.ca>
# Date 1356044645 18000
# Node ID 3af4c267a7bfe2f313fe342f793a7d265a9a6429
# Parent  f21ef87f98f1c1eeaecaf618cd2bf7f47425557e
generic simple LCSS

diff -r f21ef87f98f1 -r 3af4c267a7bf python/utils.py
--- a/python/utils.py	Fri Dec 14 01:01:55 2012 -0500
+++ b/python/utils.py	Thu Dec 20 18:04:05 2012 -0500
@@ -165,6 +165,21 @@
 # maths section
 #########################
 
+def LCSS(l1, l2, threshold, distance):
+    "returns the longest common subsequence similarity
+    based on the threshold on distance between two elements of lists l1, l2"
+    from numpy import zeros
+    m = len(l1)
+    n = len(l2)
+    similarity = zeros((m+1,n+1))
+    for i in xrange(1,m+1):
+        for j in xrange(1,n+1):
+            if distance(l1[i], l2[i])<threshold:
+                similarity[i][j] = similarity(i-1, j-1)+1
+            else:
+                similarity[i][j] = max(similarity[i-1][j], similarity[i][j-1])
+    return similarity[-1][-1]
+
 def framesToTime(nFrames, frameRate, initialTime = (0.,0.,0.)):
     'returns hour, minutes and seconds'
     from math import floor