Re: spline.m

[Daniel Heiserer]

Hi,
I've found a fitpackage in leuven belgium.
I don't know anything about it's licensing and if it contains splines (I
didn't test up to now). 
Perhaps if somebody is interested to implement he/she could
mailto:address@hidden

Here is the README:
(There is also a link to another fitpackage at the end of this README)

                                 FITPACK

FITPACK is a collection of FORTRAN programs for CURVE and SURFACE
FITTING with
SPLINES and TENSOR PRODUCT SPLINES. 

Features included are automatic knot selection, error smoothing and data 
reduction. Besides the set of data points, the user merely has to
provide a
single parameter, called the smoothing factor, to control the tradeoff
between
closeness of fit and smoothness of fit. Confidence limits for this
parameter
are available if the statistical errors on the data can be estimated.

In addition to a standard routine for curve fitting over an interval and
a  
routine for fitting a bivariate spline function to a set of scattered
data on a
rectangular domain, there are special programs for smoothing periodic
functions,
parametric curves and surfaces, functions with convexity constraints.
data over
the sphere and other non-rectangular approximation domains. Very
efficient
surface fitting routines are provided for applications with data given
either
on a rectangular, polar or spherical grid. Routines are included for
evaluation,
differentiation and integration of the spline approximations. FITPACK
also
contains an insertion algorithm and routines for calculating zeros and
Fourier 
coefficients of cubic splines.

The subdirectory ex contains a test program for each of the 29
main routines, e.g. the file mncurf.f contains a sample program for
curfit,
mnperc.f a test program for percur.f, etc. Some of the test programs
need some
input data. These can be found in the files with initials da, e.g. the
program
in mnpasu.f needs the data which are stored in dapasu, etc.

The user-level routines should be fairly well documented. Besides a
parameter
description, there is a pointer to the lower level FITPACK routines,
needed by
this particular routine. This may be useful in case only a restricted
number
of fitting routines would be needed. A user guide of approximately 300
pages
can be ordered by sending a check of 25 US dollars to
                Prof. P. Dierckx
                Department of Computer Science
                K.U.Leuven
                Celestijnenlaan 200 A
                B 3001, Heverlee, Belgium

The mathematical fundamentals of FITPACK are described in the book:
   Curve and Surface Fitting with Splines, by P. Dierckx,
   Monographs on Numerical Analysis, Oxford University Press, 1993,
   (ISBN 0-19-853441-8, 286 pages, 56 line figures)
In addition, potential FITPACK users will find there a lot of practical
advice,
illustrated with many examples, both purely academic as well as taken
from
real live. Comments on the software or the book may be addressed to the
author
via email at the following address: address@hidden
                               
Finally, it should be noted that this software has no connection with
the FITPACK software package of Alan Cline.

-- 
Mit freundlichen Gruessen
                                 Daniel Heiserer
-----
--------------------------------------------------------------
Daniel Heiserer, BMW AG, Knorrstrasse 147, 80788 Muenchen
Abteilung EK-20
Tel.: 089-382-21187, Fax.: 089-382-42820
mailto:address@hidden