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Vector Fitting

VFIT cointains version 1.0 of vectfit (routine: vectfit.m). This is an easy-to-use package, showing how to fit scalar responses and vectors of responses. It is recommended to instead use the more powerful

This package shows how to apply Vector Fitting (vectfit.m) to the rational approximation of frequency responses (scalar or vector functions). The examples explain how to specify initial poles and the significance of frequency dependent weighting. The resulting model is given in the form of pole-residue terms.


File Purpose
vectfit.m The original vector fitting routine.
manual.pdf A tutorial on how to use vectfit.m
manual.m Example case descrined in manual.m
ex1.m Scalar frequency response: fit it using vectfit.m
ex2.m Vector of 2 fequency responses: fit it using a common pole set.
ex3.m Meastured transformer admittance: fit it using a common pole set, investigate effect of weighting.
ex4.m Transmission line propagation function: Fit 5 elements with a commpon pole set.
****.txt  Frequency responses used in examples.
vector_fitting.pdf IEEE paper describing the mathematicsof Vector Fitting

Note that vectfit.m has been coded without taking advantage of the sparsity of the equations. When fitting long vectors (matrix problems) it is therefore recommended to use the routine vfit2.m which is contained in the package.