WSAHR.rar_离散系统

Notes on using MATLAB .M files accompanying the text Discrete-Time Control Problems using MATLAB and the Control Systems Toolbox by J. H. Chow, D. K. Frederick, and N. W. Chbat The MATLAB .M files accompanying the text are organized in folders from 'ch2' to 'ch10', with the RPI functions in the folder 'tools' and the models for the comprehensive problems in the folder 'models'. Users may find the following suggestions helpful. 1. Including 'tools' and 'models' in MATLAB path Use the 'addpath' command to modify the path to make the RPI functions and the model files available from any directory, the user can add a path in MATLAB pointing to these folders. The file 'set_my_path.m' can be adapted and executed at the start of each MATLAB session to set up the paths. The 'set_my_path.m' file could also be run by the startup file '/matlab/startup.m'. Comments are provided in the 'set_my_path.m' file on how to adapt the file to the user's need. Alternatively, the user can always copy the required files to the working directory. 2. Making axes equal and the 'ucircle' function Making the x- and y- axes equal is useful in certain plots such as root locus and pzmap. In MATLAB, to enforce axes to be equal, the 'axis equal' command needs to be issued before any LTI response plot command (such as 'rlocus' and 'pzmap') is used. The 'ucircle' function, which plots a unit circle, is coded to execute the 'axis equal' command. Thus the user does not have to enter this command again. Hence, the 'axis equal' command in several MATLAB scripts in the text, such as Script 2.1 on page 11, is no longer needed. To report problems with any of the m files, please email Joe Chow at chowj@rpi.edu. November 25, 2002