www.gusucode.com > rctobsolete 工具箱 matlab源码程序 > rctobsolete/mutools/commands/xnum.m
%function numstates = xnum(sys) % % Returns number of states of SYSTEM matrix. % Returns 0 for a CONSTANT or EMPTY matrix, % and -1 for a VARYING matrix. % % See also: MINFO, YNUM, UNUM. % Copyright 1991-2004 MUSYN Inc. and The MathWorks, Inc. function numstates = xnum(sys) if nargin == 0 disp('usage: numstates = xnum(sys)'); else [mtype,mrows,mcols,mnum] = minfo(sys); if strcmp(mtype,'empt') numstates = 0; elseif strcmp(mtype,'vary') numstates = -1; elseif strcmp(mtype,'cons') numstates = 0; elseif strcmp(mtype,'syst') numstates = mnum; else error('SYSTEM is invalid') end end