whether the PD anything like csound 'ftgen' opcode?
i'm interested for making function table from the list of x,y pairs
with lineral, exponential or cubic interpolation

i've made it in abstraction but only with lineral interpolation
and i think what must be some optimised external to do that

http://www.pdpatchrepo.info/hurleur/fn.rar

Not as exhaustive as Csound's GENs, but there are some curve generators in the mapping library that might help out.