Re: [Help-gsl] How to Fit an intracable formula

[Brian Gough]

Alex Brussee writes:
 > The speed functions attached to the differential steering:
 > x(t)=Amp1*((1/(tau1-tau2))*exp(t/tau1)-(1/(tau1-tau2))*exp(t/tau2))
 > y(t)=Amp2*((1/(tau3-tau4))*exp(t/tau3)-(1/(tau3-tau4))*exp(t/tau4))
 > (just to make clear that the resulting formula is indeed intracable, see 
 > also http://rossum.sourceforge.net/papers/DiffSteer/DiffSteer.html )
 > 
 > My question:
 > 1. Is there another (better) way in gsl to fit the generated path using 
 > Amp1,tau1,tau2,Amp2,tau3,tau4 to the data set ?
 > 2. Is there a way to obtain the partial derivatives by anther procedure, or 
 > did i overlook something ?

You could compute the derivatives numerically, but the analytical
formula doesn't look too complicated.

-- 
Brian Gough

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