An implementation of the Mahalanobis distane metrics suitable for integration in Weka.
Can operate on matrices with feature values or Weka instances.
You will need the Weka 3.6 jar.
Sample output
A = [2.0, 2.0] [2.0, 5.0] [6.0, 5.0] [7.0, 3.0] [4.0, 7.0] [6.0, 4.0] [5.0, 3.0] [4.0, 6.0] [2.0, 5.0] [1.0, 3.0]
B = [6.0, 5.0] [7.0, 4.0] [8.0, 7.0] [5.0, 6.0] [5.0, 4.0]
Mahalanobis distance between matrices A and B is 1.410