ON_3dVector ON_Ellipse::CurvatureAt(
double t // parameter
) const
{
ON_3dVector T, K;
ON_EvCurvature(DerivativeAt( 1, t ),DerivativeAt( 2, t ),T,K);
return K;
}
ON_3dVector ON_Ellipse::TangentAt(
double t // parameter
) const
{
ON_3dVector T = DerivativeAt( 1, t );
T.Unitize();
return T;
}
void PolyFunc::Print(ostream& os, double x) const {
const char* const T = "true";
const char* const F = "false";
os << "name = " << GetName() << endl
<< "is periodic = " << (IsPeriodic()? T: F) << endl
<< "value at " << x << " = ";
if(fabs(EvaluateAt(x)-DBL_MAX)<0.000001)
os << F<<endl;
else
os << EvaluateAt(x) << endl;
os << "is differentiable at " << x << " = "
<< (IsDifferentiable(x)? T: F) << endl;
if (IsDifferentiable(x)) {
os << "derivative at " << x << " = " << DerivativeAt(x) << endl;
}
}
ON_3dVector ON_Polyline::TangentAt( double t ) const
{
ON_3dVector v = DerivativeAt(t);
v.Unitize();
return v;
}
ON_3dVector ON_Circle::TangentAt( double t ) const
{
ON_3dVector T = DerivativeAt(1,t);
T.Unitize();
return T;
}
