public static ICurve CreateTrimmedCurve(this ICurve curve, double t0, double t1)
{
var p0 = curve.Evaluate2(t0, 0).CastArray <double>();
var p1 = curve.Evaluate2(t1, 0).CastArray <double>();
return((ICurve)curve.CreateTrimmedCurve(p0[0], p0[1], p0[2], p1[0], p1[1], p1[2]));
}