Re: [ferret_users] Polynomial Fits

[Brockmann Patrick <Patrick.Brockmann@xxxxxx>]

Stephen R. Guimond a écrit :
> Ferreters,
>  I can only find linear fit functions in the manual and wondered if 
> there are any polynomial or exponential fit functions hiding 
> somewhere.  Maybe there is an external function available for this 
> purpose?
Hi all,
I have developped an external fucntion to interpolate a variable along 
an axis
with linear, cosine, cubic and hermite methods based on algorithms 
described in
http://local.wasp.uwa.edu.au/~pbourke/other/interpolation/

The external function provided interpolates a variable on Z-AXIS but
it should be easy for each to adapt it for X,Y and T AXIS.

Sources, jnl for tests and result images are available from:
http://dods.ipsl.jussieu.fr/brocksce/ferret_ef/zinterpolate/

Comparing interpolation gives:
http://dods.ipsl.jussieu.fr/brocksce/ferret_ef/zinterpolate/test2.gif

Comparing cubic and hermite interpolation methods gives:
http://dods.ipsl.jussieu.fr/brocksce/ferret_ef/zinterpolate/spline_hermite_tension.swf

Hope that it will help
Patrick

--
LSCE/IPSL, Laboratoire CEA-CNRS-UVSQ
Data Analysis and Visualization Engineer
IPSL Global Climate Modelling Group
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