On Tue, Aug 18, 2009 at 11:27 PM, Kip Murray<[email protected]> wrote:
> Have you seen a polynomial-fitting verb for data such as iii0 10 and iii1 10 ?

Sure, and it's quite simple:

   se0=: 1 4  7 10  13  16  19  22  25  28
   se1=: 0 4 20 54 112 200 324 490 704 972
   ]p0 =: (%.[:^/~...@#) se0
1 3 7.97184e_8 _7.964e_8 4.15017e_8 _1.25439e_8 2.27913e_9
_2.45331e_10 1.44069e_11 _3.55401e_13
   p0 p. i. 10
1 4 7 10 13 16 19 22 25 28
   ]p1 =: (%.[:^/~...@#) se1
_7.96167e_11 2.1526e_7 3 1 _2.66006e_7 7.83796e_8 _1.39068e_8
1.46474e_9 _8.43371e_11 2.04392e_12
   p1 p. i. 10
_7.96167e_11 4 20 54 112 200 324 490 704 972
   NB. or, if you want lower degree polynomyals
   ]p0d2 =: (%.2^/&i.~#) se0
1 3
   p0d2 p. i. 10
1 4 7 10 13 16 19 22 25 28
   ]p1d4 =: (%.4^/&i.~#) se1
1.3074e_12 _2.50111e_12 3 1
   p1d4 p. i. 10
1.3074e_12 4 20 54 112 200 324 490 704 972

Ambrus
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