## Copyright (C) 1996 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 2, or (at your option) any 
## later version. 
## 
## Octave is distributed in the hope that it will be useful, but WITHOUT 
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
## FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License 
## for more details.
## 
## You should have received a copy of the GNU General Public License 
## along with Octave; see the file COPYING.  If not, write to the Free 
## Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. 
 
## -*- texinfo -*-
## @deftypefn {Function File } { @var{vec} = } tf2sysl (@var{vec})
##  used internally in @ref{tf2sys}.
##  strip leading zero coefficients to get the true polynomial length
## @end deftypefn

function vec = tf2sysl(vec)
## vec = tf2sysl(vec)
##
## used internally in tf2sys
## strip leading zero coefficients to get the true polynomial length


while( (length(vec) > 1) & (vec(1) == 0) )
  vec = vec(2:length(vec));
endwhile
if(vec(1) == 0)
  warning("tf2sys: polynomial has no nonzero coefficients!")
endif

endfunction