(vlax-curve-isPeriodic ename)
The vlax-curve-isPeriodic function determines whether a curve is periodic, that is, whether the parameter of its equation has an infinite range of values (both positive and negative) and the points of the curve whose parameters values differ by a value of dT (called period) coincide.
ename specifies an entity to be tested.
The function returns T if the curve is periodic, otherwise nil.
Examples
Assuming that en points to an ellipse:
: (setq en (entlast))
<EName: 057d4b67>
: (vlax-curve-isPeriodic en)
T
Assuming that en points to a spline:
: (setq en (entlast))
<EName: 078d3b65>
: (vlax-curve-isPeriodic en)
nil