The result is a scatter plot in 2 dimensions of the eigen vector associated with the largest eigen value plotted against the eigen vector associated with the second largest eigen value. This data is placed in 2D graph 1. The routine also returns the first against the third in 2D graph 2, and the second against the third in 2D graph 3, but the latter 2 are not plotted. Shows up similar objects as clusters in the graph of points. This is the most robust of the cluster methods but the most difficult to interpret.
Unclosed systems prevents a solution being calculated, and an error is produced.