Spline Toolbox    

Function Reference


This chapter contains detailed descriptions of the main commands in the Spline Toolbox. It begins with a listing of entries grouped by subject area and continues with the reference entries in alphabetical order. Not all the entries in the initial listing actually have a reference page. Those that do not appear in parentheses in the initial listing.

Information is also available through the online help facility, help splines.

For ease of use, most functions have default arguments. In the reference entry under Syntax, we first list the function with all necessary input arguments and then with all possible input arguments. The functions can be used with any number of arguments between these extremes, the rule being that if you want to specify an optional argument, you must also specify all other optional arguments (if any) to the left of it in the argument list. The rest are given default values, as specified in the manual.

As always in MATLAB, only the output arguments explicitly specified are returned to the user

Functions Listed by Category

GUIs
bspligui
Experiment with a B-spline as function of its knots
splinetool
Experiment with some spline approximation methods
Construction of Splines  
csape
Cubic spline interpolation with end conditions
csapi
Cubic spline interpolation
csaps
Cubic smoothing spline
cscvn
`Natural' or periodic interpolating cubic spline curve
getcurve
Interactive creation of a cubic spline curve
ppmak
Put together a spline in ppform
spapi
Spline interpolation
spaps
Smoothing spline
spap2
Least-squares spline approximation
spcrv
Spline curve by uniform subdivision
spmak
Put together a spline in B-form
rpmak
Put together a rational spline in rpform
rsmak
Put together a rational spline in rBform
Operators
fnbrk
Name and part(s) of a form
fncmb
Arithmetic with function(s)
fnder
Differentiate a function
fndir
Directional derivative of a function
fnint
Integrate a function
fnjmp
Jumps, i.e., f(x+) - f(x-)
fnplt
Plot a function
fnrfn
Insert additional points into the partition of a form
fntlr
Taylor coefficients or polynomial
fnval
Evaluate a function
fn2fm
Convert to specified form
Work with Breaks, Knots, and Sites  
augknt
Augment a knot sequence
aveknt
Provide knot averages
brk2knt
Breaks with multiplicities into knots
knt2brk
From knots to breaks and their multiplicities
knt2mlt
Knot multiplicities
sorted
Locate sites with respect to meshsites
aptknt
Acceptable knot sequence
newknt
New break distribution
optknt
Knot distribution `optimal' for interpolation
chbpnt
Good data sites, the Chebyshev-Demko points
Customized Linear Equation Solver
slvblk
Solve almost block diagonal linear system
bkbrk
Part(s) of an almost block-diagonal matrix

Information About Splines and the Toolbox
(spterms)
Explanation of spline toolbox terms
Demonstrations  
(spdemos)
List of demonstrations
(splexmpl)
Some simple examples
(ppalldem)
Introduction to ppform
(spalldem)
Introduction to B-form
bspline
Display a B-spline and its polynomial pieces
(bsplidem)
Some B-splines
(csapidem)
Cubic spline interpolation
(spapidem)
Spline interpolation
(histodem)
Smoothing a histogram
(csapsdem)
Cubic smoothing spline
(pckkntdm)
Knot choices
(spcrvdem)
Spline curve construction
(difeqdem)
A singularly perturbed ODE
(chebdem)
An equi-oscillating spline
(tspdem)
Tensor products
Utilities  
(franke)
Franke's bivariate test function.
(subplus)
Positive part
(titanium)
Titanium heat data
splpp
Convert left of 0 from B-form to ppform
sprpp
Convert right of 0 from B-form to ppform
spcol
B-spline collocation matrix


 Reference Functions Listed Alphabetically