Querying the LMI System Description

Recall that the full description of an LMI system is stored as a single vector called the internal representation. The user should not attempt to read or retrieve information directly from this vector. Robust Control Toolbox™ software provides three functions called lmiinfo, lminbr, and matnbr to extract and display all relevant information in a user-readable format.

lmiinfo

lminbr is an interactive facility to retrieve qualitative information about LMI systems. This includes the number of LMIs, the number of matrix variables and their structure, the term content of each LMI block, etc. To invoke lmiinfo, enter

lmiinfo(LMISYS)

where LMISYS is the internal representation of the LMI system produced by getlmis.

lminbr and matnbr

These two functions return the number of LMIs and the number of matrix variables in the system. To get the number of matrix variables, for instance, enter

matnbr(LMISYS)