ModifyJawFront.m

function plan = ModifyJawFront(plan, distance)
% ModifyJawFront is a delivery plan modification plugin for the
% TomoTherapy FMEA simulation tool.  This plugin adjusts the front jaw 
% positions by a given absolute distance, in mm. In this frame of
% reference, positive means a larger field width and vice versa.
%
% The following variables are required for proper execution: 
%   plan: a structure containing the TomoTherapy delivery plan. See
%       LoadPlan for more information on the structure format.
%   distance: a number (or string) indicating the deviation in front jaw 
%       positions, in mm.
%
% The following variable is returned upon succesful completion:
%   plan: a structure, of the same format as the input delivery plan, with
%       the modified jaws.
%
% Author: Mark Geurts, mark.w.geurts@gmail.com
% Copyright (C) 2014 University of Wisconsin Board of Regents
%
% 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 3 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, see http://www.gnu.org/licenses/.

% If the second variable is not already numeric
if ~isnumeric(distance)
    
    % Parse it as a double
    distance = str2double(distance);
    
end

% Log event
Event(sprintf('Adjusting front jaws by %0.2f mm', distance));

% Loop through delivery plan events
for i = 1:size(plan.events, 1)
    
    % If the event specifies front jaw
    if strcmp(plan.events{i,2}, 'jawFront') 
    
        % Modify the event value
        plan.events{i,3} = plan.events{i,3} + distance / 850;
        
    end
end