Creating a cylinder by specifying a center point and a "revolved" line.
$$
$$ Declarations
$$
ENTITY/PT1,LN1,CYL1
$$
$$ Geometry Definition
$$
PT1 =POINT/0,0
LN1 =LINE/1,0,1,0,1,-1
$$
$$ Cylinder Definition
$$
CYL1=CYLNDR/CENTER,PT1,LN1
Cylinder Generated by Revolving a Line about an Imaginary Axis