This data frame contains three variables which comprise a set of points uniformly distributed in a three-dimensional sphere, except that a central slice of the points has been removed. The slice of data points removed is oriented so that all the two-dimensional projections appear to be data points uniformly distributed over a disk, and the initial three-dimensional view is such that the slice is not visible. You can quickly see the slice by spinning the 3D view of the data.
Simulated data.
brush(sliced.ball)