Bug in SplineFit ?
- To: mathgroup at yoda.physics.unc.edu
- Subject: Bug in SplineFit ?
- From: Jean.Peccoud at imag.fr (Jean Peccoud)
- Date: Tue, 8 Mar 1994 15:35:46 +0100
> >Dear Mathgroup : > >can anybody explain me this amazing behaviour of SplineFit ? (*w2 is CompositeBezier interpolation of a data set produced by SplineFit in NumericalMath`SplineFit`*) >(zenon) In[12]:= >w2 > >(zenon) Out[12]= >SplineFunction[CompositeBezier,{0., 8.},<>] > >(zenon) In[13]:= >w2[5] > >(zenon) Out[13]= >{0.75, 1.80523} > >(zenon) In[15]:= >FindRoot[w2[x][[1]]==0.76, {x, 5}, MaxIterations->1000] > >(zenon) Out[15]= >{x -> 5.26073} > >(zenon) In[16]:= >FindRoot[w2[x][[2]]==-1.96, {x, 5}, MaxIterations->1000] > >Part::partw: Part 2 of SplineFunction[CompositeBezier,{0., 8.},<>][x] does not >exist. > (*Why Part2 does not exit*) > >Part::pspec: Part specification #2 is neither an integer nor a list of >non-zero integers. > >FindRoot::frjc: Could not symbolically find the Jacobian of {w2[x][[2]] - >-1.96} > . Try giving two starting values for each variable. > >(zenon) Out[16]= >FindRoot[w2[x][[2]] == -1.96, {x, 5}, MaxIterations -> 1000] Thank you for helping me. ----------------------------------- Jean Peccoud TIMC-IMAG Faculte de medecine de Grenoble F-38700 La Tronche France tel : (33) 76 63 71 85 fax : (33) 76 51 86 67 E-mail : Jean.Peccoud at imag.fr