.ApproxSpline.Surf2d.derivative

Interface

function derivative
  extends Modelica.Icons.Function;
  input ApproxSpline.Surf2d.Type s "2-D spline object to operate on";
  input Real x "first independent variable where spline is to be evaluated";
  input Real y "second independent variable where spline is to be evaluated";
  input Real ddx "value of the 1st partial derivative";
  input Real ddy "value of the 2nd partial derivative";
  output Real dz "evaluated value ";
end derivative;