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04/08/10 1:38pm

To quote a previous (successfully answered) query:

I have multiple datasets, and one function that depend on multiple
parameters, of which I would like to find a global best fit to three of the
parameters. However, within each dataset, I need to specify slightly
different parameters within the function. For example (not actual function
and will not make sense),
f(a_,b_,c_,d_,e_) = a*x^5 + b*x^4 + c*x^3 + d*x^2 + e*x
In datasets 1-5, I would like to specify different "a" and "b" values (for
each dataset), while finding the best single fit (global) for "c," "d," and
"e" in the function using all datasets.

I know quote the proposed solution:

You could e.g. add an additional first coordinate x0 to your data
points, that indicates the data set, and define f (I call the known
parameters a and b and the unknown p1,p2,p3):
x0==1, f[x,a1,b1,p1,p2,p3],
x0==2, f[x,a2,b2,p1,p2,p3],
x0==3, f[x,a3,b3,p1,p2,p3],
x0==4, f[x,a4,b4,p1,p2,p3],
x0==5, f[x,a5,b5,p1,p2,p3]
Then you would call FindFit:


My problem is that I don't know how to define individual datasets, i.e. how to say that the dataset where x0==1 is the same as data0={{1,2},{2,4},{4,8}}
Any help greatly appreciated

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Subject (listing for 'How to identify different datasets')
Author Date Posted
How to identify different datasets Conor 04/08/10 1:38pm
Re: How to identify different datasets Conor 04/09/10 07:38am
Re: How to identify different datasets anika 02/15/11 7:51pm
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