% function out = spoles(sys)
%
%   Eigenvalues of the A matrix of a SYSTEM matrix.
%
%   See also: EIG, RIFD and SZEROS.

function out = spoles(sys)
 if nargin ~= 1
   disp('usage: out = spoles(sys)')
   return
 end
 [mtype,mrows,mcols,mnum] = minfo(sys);
 if mtype == 'syst'
   if mnum == 0
     disp('input matrix has no states')
   else
     out = eig(sys(1:mnum,1:mnum));
   end
 else
   error('input matrix is not a SYSTEM matrix')
   return
 end
%
% Copyright MUSYN INC 1991,  All Rights Reserved
