LTPDA Toolbox™

Converting models between different representations

The different constructors from each transfer function representations accept as an input a model from a another representation so that they can all be converted between the different representations. In the current LTPDA version, this applies for pole/zero model and rational representation. Following versions will cover the partial fraction representation. This is shown in the following transformation table:

From pzmodel to rational

You can transform a pzmodel into a rational by typing:

    >> rat   = rational(pzmodel)

From rational to pzmodel

You can transform a rational into a pzmodel by typing:

    >> rat   = pzmodel(rational)

Algorithm

To translate from rational to pzmodel representation we need to compute the roots of a polynomial and the inverse operation is performed going from pzmodel to rational. More information about the algorithm used can be found in MATLAB's functions poly and roots.

Rational representation

Converting models to digital filters