code: void set(final double m, final Object pt) {
  		if (m == 0.0) {
  			if (count != 0) {
  				clusters.space.setToOrigin(m1);
  				clusters.space.setToOrigin(m2);
  			}
  		} else {
  			clusters.space.setToScaled(m1, m, pt);
  			clusters.space.setToScaledSqr(m2, m, pt);
  		}
  		count = 1;
  		m0 = m;
  		var = 0.0;
  	}
docs: Sets this cluster equal to a single point.
  
  @param m
  the mass of the point
  @param pt
  the coordinates of the point