real function pda_splint(t,n,c,k,a,b,wrk)
function pda_splint calculates the integral of a spline function s(x)
of degree k, which is given in its normalized b-spline representation
calling sequence:
aint = pda_splint(t,n,c,k,a,b,wrk)
input parameters:
t : array,length n,which contains the position of the knots
of s(x).
n : integer, giving the total number of knots of s(x).
c : array,length n, containing the b-spline coefficients.
k : integer, giving the degree of s(x).
a,b : real values, containing the end points of the integration
interval. s(x) is considered to be identically zero outside
the interval (t(k+1),t(n-k)).
output parameter:
aint : real, containing the integral of s(x) between a and b.
wrk : real array, length n. used as working space
on output, wrk will contain the integrals of the normalized
b-splines defined on the set of knots.
other subroutines required: pda_fpintb.
references :
gaffney p.w. : the calculation of indefinite integrals of b-splines
j. inst. maths applics 17 (1976) 37-41.
dierckx p. : curve and surface fitting with splines, monographs on
numerical analysis, oxford university press, 1993.
author :
p.dierckx
dept. computer science, k.u.leuven
celestijnenlaan 200a, b-3001 heverlee, belgium.
e-mail : Paul.Dierckx@cs.kuleuven.ac.be
latest update : march 1987