function c=tnnusarv(l1,s1,ea1)
# computed a characteristic parameter of beam-column member
# l1 - length of member
# s1 - axial force
# ea1 - bending stiffness of the element
# 
##=========================================================================
## This Program is written by Andres Lahe,   1998-05-21
##                    e-mail: andres.lahe@ttu.ee
## LAST MODIFIED: Andres Lahe,   2009-02-17
## Copyright (c)  1998 by Tallinn University of Technology 
##                Department of Mechanics
##                http://www.ttu.ee/
##
## This program 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
## of the License, or (at your option) any later version.

## This program 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 this program; if not, write to the Free Software
## Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
## http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
##==========
##
  s2=abs(s1);
 if s2 ==0
  c=0;
 else
  c=l1*sqrt(s2/ea1);
 end
%
endfunction


 
