Re: polinterpolate on reciprocals

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Thu, Oct 19, 2017 at 07:13:36PM +1100, Kevin Acres wrote:
> I noticed this effect today:
> 
> ? polinterpolate([6,15,28,45,66,91])
> 2*x^2 + 3*x + 1
> ? polinterpolate([1/6,1/15,1/28,1/45,1/66,1/91])
> -17/61776*x^5 + 6289/1081080*x^4 - 21139/432432*x^3 + 15997/77220*x^2 -
> 27509/60060*x + 1384/3003
> 
> In the second example I would have expected 1/(2*x^2 + 3*x + 1) rather
> than the value given.

polinterpolate interpolates as a polynomial function, not as a rational
function.

There are algorithms to interpolate as a rational functions but they are
not implemented.

Cheers,
Bill.