As of Version 7.0, Ellipsoid has been moved to the Multivariate Statistics package.


represents a p-dimensional ellipsoid centered at the point {x1,,xp} with semi-axis radii ri aligned with the coordinate axes.


represents a p-dimensional ellipsoid with semi-axis radii ri aligned with the direction di.


  • To use Ellipsoid, you first need to load the Regression Common Functions Package. You can do this by using Needs["MultivariateStatistics`"], which will automatically load the Regression Common Functions Package, or you can load the package directly by using Needs["RegressionCommon`"].
  • Ellipsoid is used to represent ellipsoidal regions such as EllipsoidQuantile and EllipsoidQuartiles.
  • Two-dimensional Ellipsoid objects can be plotted using Graphics.
  • If the direction matrix {d1,,dp} is a permutation of the identity matrix, the direction matrix is automatically dropped, reordering the radii if necessary.