This is computed only on bifurcation. If n1 is the number of tips on the left and n2 on the right. Asymmetry return abs(n1-n2)/(n1+n2-2)
 

Asymmetry is: |?-d|/(?+d -2)

                       i.e. ?=3 (red points)

                       d=1(azure point)

                             A=|3-1|/(3+1-2)=1
Metric Total_Sum #Compartments
(considered)		 #Compartments
(discarded) 		Minimum Average Maximum S.D
Partition_asymmetry 61 102 (1452) 0 0.6 1 0.44377

The above example returns the total sum of the Partition_asymmetry at each bifurcation point, minimum, average and maximum values according to standard output of Lmeasure.