function DeltaR = xb_calc_DeltaR(dims,zb)
%UNTITLED  Calculate dune crest retreat for the Delta Basin experiments
%
%   Calculate dune crest retreat for the Delta Basin experiments H5019.50.
%   The retreat point R* is defined as the x-coordinate of the grid point
%   situated fartest seaward and in which zb >= 0.165 m.
%
%   Syntax:
%   varargout = Untitled(varargin)
%
%   Input:
%   varargin  = simdir (Location of xboutput.nc file
%
%   Output:
%   varargout = DeltaR (Matrix with DeltaR*(t,y))

%% Copyright notice
%   --------------------------------------------------------------------
%   Copyright (C) 2011 <COMPANY>
%       Bram de Vries
%
%       <EMAIL>	
%
%       <ADDRESS>
%
%   This library is free software: you can redistribute it and/or
%   modify it under the terms of the GNU Lesser General Public
%   License as published by the Free Software Foundation, either
%   version 2.1 of the License, or (at your option) any later version.
%
%   This library 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
%   Lesser General Public License for more details.
%
%   You should have received a copy of the GNU Lesser General Public
%   License along with this library. If not, see <http://www.gnu.org/licenses/>.
%   --------------------------------------------------------------------

% This tool is part of <a href="http://OpenEarth.nl">OpenEarthTools</a>.
% OpenEarthTools is an online collaboration to share and manage data and 
% programming tools in an open source, version controlled environment.
% Sign up to recieve regular updates of this function, and to contribute 
% your own tools.

%% Version <http://svnbook.red-bean.com/en/1.5/svn.advanced.props.special.keywords.html>
% Created: 13 May 2011
% Created with Matlab version: 7.9.1.705 (R2009b) Service Pack 1

% $Id$
% $Date$
% $Author$
% $Revision$
% $HeadURL$
% $Keywords: $


%% Calculate R*
RetreatPoint(size(zb,1),size(zb,2))=0;
for i=1:size(zb,1)
    for j=1:size(zb,2)
        RetreatPoint(i,j) = ( find(zb(i,j,:) >= 0.165, 1) );
    end
end


%% Calculate DeltaR*
DeltaR(size(RetreatPoint,1),size(RetreatPoint,2))=0;
for i=1:size(RetreatPoint,1)
    for j=1:size(RetreatPoint,2)
        DeltaR(i,j) = dims.x(1,RetreatPoint(i,j)) - dims.x(1,RetreatPoint(1,j));
    end
end