-- nderiv.adb compute formulas for numerical derivitives
--            order is order of derivitive, 1 := first derivitive, 2 := second
--            points is number of points where value of function is known
--            f(x1), f(x2), f(x3) ... f(x points)
--            term is the point where derivitive is computer
--            f'(x1) := (1/bbh)*( a(1)*f(x1) + a(2)*f(x2)
--                     + ... + a(points)*f(x points)

-- algorithm: use divided differences to get polynomial p(x) that
--            approximates  f(x).  f(x):=p(x)+error term
--            f'(x) := p'(x) + error term'
--            substitute xj := x1 + (j-1)*h
--            substitute x := x1 to get  p'(x1) etc

with Integer_Arrays; use Integer_Arrays;

procedure  nderiv(order   : Integer; -- first derivitive is 1, second is 2, etc
                  npoints : Integer; -- number of points used to compute
                  point   : Integer; -- compute derivitive at this point 1, 2,
                  a       : out Integer_Vector; -- integer coefficients
                  bb      : out Integer);    -- denominator