Function File: [scaledsys, info] = prescale (sys)

Scale state-space model. The scaled model scaledsys is equivalent to sys, but the state vector is scaled by diagonal transformation matrices in order to increase the accuracy of subsequent numerical computations. Frequency response commands perform automatic scaling unless model property scaled is set to true.

Inputs

sys

LTI model.

Outputs

scaledsys

Scaled state-space model.

info

Structure containing additional information.

info.SL

Left scaling factors. Tl = diag (info.SL).

info.SR

Right scaling factors. Tr = diag (info.SR).

Equations

Es = Tl * E * Tr
As = Tl * A * Tr
Bs = Tl * B
Cs =      C * Tr
Ds =      D

For proper state-space models, Tl and Tr are inverse of each other.

Algorithm
Uses SLICOT TB01ID and TG01AD by courtesy of NICONET e.V..

Package: control