Knot selection for least squares approximation using thin plate splines.
McMahon, John R.
Schelin, Charles W.
MetadataShow full item record
Given a large set of scattered data (x(i),y(i) ,f(i)), a method for selecting a significantly smaller set of knot points which will represent the larger set is described, leading to a package of FORTRAN subroutines. The selection of the knot point locations is based on the minimization of the sum of the squares of the difference between the average number of points per Dirichlet tile and the actual number of points in each tile, subject to the constraint that each knot is located at the centroid of its tile. The pertinent theoretical and computational aspects of the subroutines are introduced and described in detail. Using the least squares thin plate spline approximation method for constructing surfaces, various test surfaces are examined and compared to surfaces obtained using smoothing splines and the bicubic Hermite approximation method. The FORTRAN subroutines are made available to prospective users through a point of contact.
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Digital computer program for flexural analysis of beams Lowe, Gary B. (Monterey, California: U.S. Naval Postgraduate School, 1963);This paper describes a solution to the flexural analysis of a beam by digital computer. Subroutines were written which calculate shear, moment, slope and deflection at any specified point on a beam if the loading is ...
Simulation methods for Poisson processes in nonstationary systems Lewis, Peter A. W.; Shedler, Gerald S. (Monterey, California. Naval Postgraduate School, 1978-08); NPS55-78-019The nonhomogeneous Poisson process is a widely used model for a series of events (stochastic point process) in which the rate or intensity of occurrence of points varies, usually with time. The process has the characteristic ...
A diagonal-mass-matrix triangular-spectral-element method based on cubature points Giraldo, F.X.; Taylor, M. A. (2006);The cornerstone of nodal spectral-element methods is the co-location of the interpolation and integration points, yielding a diagonal mass matrix that is efficient for time-integration. On quadrilateral elements, ...