basis splines for interpolation (not fitting)

[Simon Wiesheier]

Dear all,

can I use basis splines for interpolation and not fitting?

Or, say I already computed the control points ai (f = sum_i B_i a_i) and
all what I want to do is
to evaluate the basis spline B_i, for which we need (i) a knot vector
(t_i,...,t_i+k) that describes the support of B_i and (ii) the order of the
spline k.

Are there classes / types that allow me to do that?

Best,
Simon