__tfl__.m

similer program for matlab

## Copyright (C) 1996, 2004, 2005, 2007
##               Auburn University.  All rights reserved.
##
## This file is part of Octave.
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## Undocumented internal function.

## -*- texinfo -*-
## @deftypefn {Function File} {} __tfl__ (@var{vec})
## used internally in tf.
## strip leading zero coefficients to get the true polynomial length
## @end deftypefn

function vec = __tfl__ (vec)

  while (length (vec) > 1 && vec(1) == 0)
    vec = vec (2:end);
  endwhile

  if (vec(1) == 0)
    warning ("tf: polynomial has no nonzero coefficients!")
  endif

endfunction