#### 5.8 Button ’Sphere’

The sphere-button constructs a sphere if suitable objects are selectd, or shows a popup-menu
with all possibilities to construct a sphere.

To construct a sphere with a given length (e. g. 7 l.u.), one has to create a vector of
that length first (e. g. by entering ’v=(7,0,0)’ at the command-line) and use this as the
radius.