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

 Messages: [ Previous | Next ]
 Marnie Northington Posts: 1,251 Registered: 12/13/04
Re: Help with formula (revised question)
Posted: Nov 20, 2013 1:17 PM

"Robert Crandal" <noreply2me@yahoo.com> wrote in message
>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 but you may have to unwrap the link:

http://www.wolframalpha.com/input/?i=interpolate+%280%2C1%29%2C%280.1%2C1%29%2C%280.5%2C1%29%2C%280.9%2C1%29%2C%281%2C1%29%2C%281.03%2C2%29%2C%281.5%2C2%29%2C%281.8%2C2%29%2C%282%2C2%29%2C%282.3%2C3%29%2C%283%2C3%29%2C%283.2%2C4%29

Whether this polynomial gives sensible results between your points or
outside the range of your data is anybody's guess.

Old Guy

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