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subroutine fpdisc(t,n,k2,b,nest)
c subroutine fpdisc calculates the discontinuity jumps of the kth
c derivative of the b-splines of degree k at the knots t(k+2)..t(n-k-1)
c ..scalar arguments..
integer n,k2,nest
c ..array arguments..
real*8 t(n),b(nest,k2)
c ..local scalars..
real*8 an,fac,prod
integer i,ik,j,jk,k,k1,l,lj,lk,lmk,lp,nk1,nrint
c ..local array..
real*8 h(12)
c ..
k1 = k2-1
k = k1-1
nk1 = n-k1
nrint = nk1-k
an = nrint
fac = an/(t(nk1+1)-t(k1))
do 40 l=k2,nk1
lmk = l-k1
do 10 j=1,k1
ik = j+k1
lj = l+j
lk = lj-k2
h(j) = t(l)-t(lk)
h(ik) = t(l)-t(lj)
10 continue
lp = lmk
do 30 j=1,k2
jk = j
prod = h(j)
do 20 i=1,k
jk = jk+1
prod = prod*h(jk)*fac
20 continue
lk = lp+k1
b(lmk,j) = (t(lk)-t(lp))/prod
lp = lp+1
30 continue
40 continue
return
end
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