[Jprogramming] Takes from a mystery sequence

[Kip Murray]

Thank you, Ambrus, I will study your verbs.  Of course I would like the lowest 
degree that fits the data.  I'm assuming data that has an exact polynomial fit.

Kip

Zsbán Ambrus wrote:
> On Tue, Aug 18, 2009 at 11:27 PM, Kip Murray<km at math.uh.edu> 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 =: (%.[:^/~i.@#) 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 =: (%.[:^/~i.@#) 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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