392 APPENDICES
The functionally equivalent commands will be listed, in each sub-section, for
convenience. A more detailed discussion is given to illustrate the more subtle differences
in the mu and D-Kiteration aspects. More importantly, the Himat demo is available in
both µ-Toolsand Xµ. Fora fast start on moving between platforms, study these demos
side by side.
A.1 Data Objects
The underlying data structure in Matlab is the complex valued matrix, whereas in
Xmath there variousother ob jects available: polynomials,transfer functions, parameter
dependent matrices, and dynamic systems.
system/Dynamic System Functions
The µ-Tools functions for creating and manipulating the systemmatrix have no Xµ
equivalentas the underlying Xmath operators can directly handle the dynamic system
and transfer function data objects.
Also residing within the Xmath state-space object is the initial state. This is used
primarily for time response calculations. It is debatable whether or not the initial state
is an intrinsic attribute of the system as one frequently changes it for simulation. It does
have the advantageof reducing the time response calculation to a simple multiplication
and it can easily be changed without accessing all of the other system variables.
The following table illustrates the equivalentfunctions, or indicates the data ob jects
which provide the same functionality.