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subroutine fpbspl(t,n,k,x,l,h)
c subroutine fpbspl evaluates the (k+1) non-zero b-splines of
c degree k at t(l) <= x < t(l+1) using the stable recurrence
c relation of de boor and cox.
c Travis Oliphant 2007
c changed so that weighting of 0 is used when knots with
c multiplicity are present.
c Also, notice that l+k <= n and 1 <= l+1-k
c or else the routine will be accessing memory outside t
c Thus it is imperative that that k <= l <= n-k but this
c is not checked.
c ..
c ..scalar arguments..
real*8 x
integer n,k,l
c ..array arguments..
real*8 t(n),h(20)
c ..local scalars..
real*8 f,one
integer i,j,li,lj
c ..local arrays..
real*8 hh(19)
c ..
one = 0.1d+01
h(1) = one
do 20 j=1,k
do 10 i=1,j
hh(i) = h(i)
10 continue
h(1) = 0.0d0
do 20 i=1,j
li = l+i
lj = li-j
if (t(li).ne.t(lj)) goto 15
h(i+1) = 0.0d0
goto 20
15 f = hh(i)/(t(li)-t(lj))
h(i) = h(i)+f*(t(li)-x)
h(i+1) = f*(x-t(lj))
20 continue
return
end
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