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U.S. Department of Energy
Office of Scientific and Technical Information

FC,LSEI,WNNLS. Constrained Least Squares Fit

Technical Report ·
OSTI ID:138720
;  [1]
  1. Sandia National Labs., Albuquerque, NM (United States)

FC allows a user to fit discrete data, in a weighted least-squares sense, using piece-wise polynomial functions represented by B-splines on a given set of knots. In addition to the least-squares fitting of the data, equality, inequality, and periodic constraints at a discrete, user-specified set of points can be imposed on the fitted curve or its derivatives. The subprograms LSEI and WNNLS solve the linearly-constrained least-squares problem. LSEI solves the class of problem with general inequality constraints, and, if requested, obtains a covariance matrix of the solution parameters. WNNLS solves the class of problem with nonnegativity constraints. It is anticipated that most users will find LSEI suitable for their needs; however, users with inequalities that are single bounds on variables may wish to use WNNLS.

Research Organization:
Sandia National Labs., Albuquerque, NM (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
AC04-76DP00789
OSTI ID:
138720
Report Number(s):
ESTSC--000580C660000; NESC--909
Country of Publication:
United States
Language:
English