X = [0.0 10.0;
     1.0 0.0];
Y = [0.0 -1.0;
    -1.0 0.0];
Z = [0.0 -1.0;
    -1.0 0.0;
    0.5, 5.0];
emd(X, Y)

[d, flow] = emd(X, Y)

[d, flow] = emd(X, Z)