how to interpolate a closed curve ?

I try like this:

first using rhinointerpcurve creat a curve,

and then using rhinomakecurveclosed make this curve closed

but the closed curve will not smoth at the start and end point.

One optional argument for the CreateInterpolatedCurve method is CurveKnotStyle, choosing a “periodic” style should close the curve smoothly.

```
0 Uniform Parameter spacing between consecutive knots is 1.0.
1 Chord Chord length spacing, requires degree=3 with CV1 and CVn1 specified.
2 ChordSquareRoot Square root of chord length, requires degree=3 with CV1 and CVn1 specified.
3 UniformPeriodic Periodic with uniform spacing.
4 ChordPeriodic Periodic with chord length spacing.
5 ChordSquareRootPeriodic Periodic with square roor of chord length spacing.
```

–Mitch