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 Author Comment/Response Conor 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): f[x0_,x_,p1_,p2_,p3_]:=Which[ 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: FindFit[data,f[x0,x,x2,x3,x4,x5],{p1,p2,p3},{x0,x}] 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 URL: ,

 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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