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Topic: Help with formula (revised question)
Replies: 7   Last Post: Nov 20, 2013 8:15 PM

 Messages: [ Previous | Next ]
 Peter Percival Posts: 2,623 Registered: 10/25/10
Re: Help with formula (revised question)
Posted: Nov 20, 2013 7:38 AM

Robert Crandal wrote:
> I asked a similar question earlier. Thank you
> everyone who tried helping. However, I'd now
> like to revise the data and requirements.
> Here is the new data set:
>
> X Y
> -- --
> 0.0 1
> 0.1 1
> 0.5 1
> 0.9 1
> 1.0 1
> 1.03 2
> 1.5 2
> 1.8 2
> 2.0 2
> 2.3 3
> 3.0 3
> 3.2 4
>
> X is a positive real number greater than or equal
> to zero (or 0.0). Y is an integer as seen in the
> second column above.
>
> Can this data be represented with a formula
> that only uses either addition, subtraction,
> multiplication, division, modulus, or the power (^)
> function, or any combination of these?

Yes! Use Lagrange's interpolation formula as referred to in my post of
18/11/2013 18:56 (GMT, presumably) in your thread 'Help with creating a
function'. The resulting function is a polynomial and can be found
whenever there are a finite number of X's each with just one
corresponding Y.

--
Madam Life's a piece in bloom,
Death goes dogging everywhere:
She's the tenant of the room,
He's the ruffian on the stair.

Date Subject Author
11/20/13 Robert Crandal
11/20/13 William Elliot
11/20/13 Jussi Piitulainen
11/20/13 Peter Percival
11/20/13 James Waldby
11/20/13 Marnie Northington
11/20/13 Barry Schwarz
11/20/13 Rock Brentwood