fpdisc.f

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      subroutine fpdisc(t,n,k2,b,nest)
      implicit none
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