These two documents DO NOT reconciliate the Ridder derivative operator.
They reconciliate wrt the Smath derivative operator that does not parse
a constrained function. The proposal considers only the 1rst derivative.

Jean

Finite Differences DERIV Parametric.sm (9 KiB) downloaded 54 time(s). => read first

Finite Differences [Fnct, Deriv, Cumul].sm (65 KiB) downloaded 48 time(s). => read next