A New Library of Subroutines for Calculating Smoothing Splines.

Abstract

Defense Research Establishment Atlantic has, at present, two libraries containing subroutines for calculating splines: IMSL and BSPLIN. A new library has been developed to supplement the IMSL and BSPLIN routines in the realm of smoothing splines. It is not self-contained, making frequent use of subroutines from the BSPLIN library. The new subroutines offer several advantages over the smoothing spline subroutines in the IMSL and BSPLIN libraries: (1) The order of the spline may be picked by the user; (2) The second derivative of the spline is not constrainted to be zero at its end-points; (3)The user of the new subroutines has freedom to choose the number and positions of the knots of the spline; and (4) The new subroutines have, as input, an extra set of weights, delta sub i, i= 1,N, which control the stiffness of the spline between each pair of knots. The new subroutines were initially developed for use in ship hull approximation for the calculation of boundary layer growth on the hull. For this calculation one needs splines whose second derivatives are very well behaved. The additional control afforded by the new subroutines makes them far more suitable for this application than any of the subroutines makes them far more for this application than any of the subroutines currently available in either the IMSL or BSPLIN libraries. Keywords: Canada; French language.(Author)

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1985
Accession Number
ADA158049

Entities

People

  • D. Hally

Organizations

  • Defence Research and Development Canada

Tags

DTIC Thesaurus Topics

  • Algorithms
  • Boundaries
  • Boundary Layer
  • Computer Programs
  • Computers
  • Data Sets
  • Fluid Flow
  • Interpolation
  • Language
  • Layers
  • Linear Systems
  • National Security
  • Procedures (Computers)
  • Security
  • Ship Hulls
  • Standards
  • Stiffness

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  • Approximation Theory.
  • Database Systems and Applications