There exists an algorithm for construction interpolating quadratic splines which preserves the monotony of the data.The taper curves formed with threadheaders.shop this algorithm, QO-splines, have many good qualities when a sufficient number of measured diameters of a tree is available.In fact, they may even be superior to certain shape preserving taper curves, MR-splines.
This algorithm can be modified to preserve also the shape of the data.In the present paper, the quality of taper curves constructed by a new shape preserving from of the algorithm is examined.For this purpose, taper curves are formed for different sets of measurements and their properties are compared with the ones of QO-splines and MR-splines.
The results indicate that these new shape-preserving taper curves are in general better than QO-splines and Military Airplane MR-splines even if the differences may be small in many cases.The superiority is the clearer the less measurements are available.The PDF includes an abstract in Finnish.