COMSOL Multiphysics™

BSplineCurve
BSplineCurve
Supported Versions 0
Subtype of
Fields
BSplineMfd
The class is defined by the following fields
ENTITY/
OBJECT
integer
BSplineMfd
DESCRIPTION
Version
Parent class containing common data
Description
The BSplineCurve, describes a general spline curve, using B-spline basis functions,
as defined in BSplineMfd. Splines on this form are often referred to as B-splines.
A pth-degree spline curve is defined by
C( u)
=
n
∑
i = 0
p
∑
i = 0
p
N i ( u)wi
P i
--------------------------------------- , a ≤ u ≤ b
p
N i ( u)wi
where P i are the control points., the wi are the weights and the N i p are the pth
degree B-spline basis functions defined in the nonperiodic and nonuniform knot
vector
U = { a , … , au , , p + 1
… , u , m – p – 1
b , … , b}
For non-rational B-splines, all weights are equal to 1 and the curve can be expressed
as
n
∑
C( u) = p
N i ( u)wi
P ,
i
i = 0
a≤
u≤
b
See also
BezierCurve
436 | CHAPTER 3: THE COMSOL MULTIPHYSICS FILES