gram.m

来自「similer program for matlab」· M 代码 · 共 41 行

## Copyright (C) 1996, 2000, 2003, 2004, 2005, 2007
##               Auburn University. All rights reserved.
##
## This file is part of Octave.
##
## Octave is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or (at
## your option) any later version.
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## General Public License for more details.
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## along with Octave; see the file COPYING.  If not, see
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## -*- texinfo -*-
## @deftypefn {Function File} {} gram (@var{a}, @var{b})
## Return controllability gramian @var{m} of the continuous time system
## @math{dx/dt = a x + b u}.
##
## @var{m} satisfies @math{a m + m a' + b b' = 0}.
## @end deftypefn

## Author: A. S. Hodel <[e-mail]>

function m = gram (a, b)

  if (nargin != 2)
    print_usage ();
  endif

  ## Let lyap do the error checking...

  m = lyap (a, b*b');

endfunction