Numerical Aspects in Locating the Corner of the L-curve

  • Valia Guerra
  • Victoria Hernández


The L-curve method can be used to choose the regularization parameter, when discrete ill-posed problems are solved by a regularization method. In this paper, we propose a novel numerical algorithm for locating the corner of the L-curve when only a finite set of its points is known. The proposed technique is based on conic section fitting. The corner point is chosen to be the nearest one to the shoulder point of the conic. The performance of the method is assessed by comparing its results with those obtained with another approach reported previously by Hansen [6].


Singular Value Decomposition Regularization Method Corner Point Tikhonov Regularization Conic Section 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Valia Guerra
    • 1
  • Victoria Hernández
    • 1
  1. 1.Centro de Matemática y Física TeóricaMinisterio de CienciaHavanaCuba

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