Main Content

Left normalized coprime factorization

computes
the left normalized coprime factorization of the dynamic system model
`fact`

= lncf(`sys`

)`sys`

. The factorization is given by:

$$sys={M}_{l}^{-1}{N}_{l},\text{\hspace{1em}}{M}_{l}{M}_{l}^{*}+{N}_{l}{N}_{l}^{*}=I.$$

Here, $${M}_{l}^{*}$$ denotes the conjugate of *M _{l}* (see

`ctranspose`

). .
The returned model `fact`

is a minimal state-space realization of the
stable system
[`ncfmr`

) and controller synthesis (`ncfsyn`

).`fact`

is a minimal realization of`[Ml,Nl]`

. If you need to use`[Ml,Nl]`

or`[Ml,Nl]'`

in a computation, it is better to use`fact`

than to concatenate the factors yourself. Such manual concatenation results in extra (nonminimal) states, which can lead to decreased numerical accuracy.