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Manuscript Title: A regularization method for nonlinear ill-posed problems.
Authors: J. Weese
Program title: NLREG
Catalogue identifier: ACGH_v2_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 77(1993)429
Programming language: Fortran.
Computer: SUN SPARCSTATION.
Operating system: UNIX.
RAM: 2000K words
Word size: 32
Supplementary material: A user manual is available.
Keywords: General purpose, Fit, Ill-posed problem, Tikhonov regularization, Nonlinear integral Equation, Nonlinear regularization.
Classification: 4.9.

Nature of problem:
Physically interesting functions are often not directly accessible by an experiment, and must be calculated from data of an experimental accessible quantity. In many cases this calculation requires the inversion of a nonlinear integral equation, and a nonlinear regularization method should be applied.

Solution method:
The nonlinear regularization method is a generalization of the linear regularization method the program FTIKREG (for Fast TIKhonov REGularization) [1] is based on.

Running time:
The running time is proportional to (n+ns)*ns**2, where n denotes the number of data points and ns is the number of points at which the result is calculated.

References:
[1] J. Weese, Comput. Phys. Commun. 69(1992)99.