def med(X, Y): # computes a matching by calculating the pairwise edit distance
filename = IO.getEditDistFilename(X, Y)
if os.path.isfile(filename):
print 'found file', filename
D = IO.readNumpyArray(filename)
else:
print 'file', filename, 'not found'
D = strings.pweditdist(X, Y)
IO.writeNumpyArray(filename, D)
(cost, pi, edge_cost) = MU.ApproxMatch(D)
# TODO:
# 3. set up an initial matching based on edit distance.
return cost, pi, edge_cost
