ModifyIso.m

function plan = ModifyIso(plan, varargin)
% ModifyIso is a delivery plan modification plugin for the TomoTherapy FMEA 
% simulation tool.  This plugin adjusts the isocenter position by a given 
% absolute distance, in mm, along the direction (X, Y, or Z), where X,Y,Z 
% refer to the dose calculation coordinate system. Movement in multiple
% directions is possible by supplying more than three input arguments.
%
% 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.
%   varargin{odd}: a number (or string) indicating the deviation in 
%       isocenter position, in mm.
%   varargin{even}: 'X', 'Y', or 'Z' indicating the direction to apply the
%       adjustment.
%
% The following variable is returned upon succesful completion:
%   plan: a structure, of the same format as the input delivery plan, with
%       the modified isocenter position.
%
% Author: Mark Geurts, mark.w.geurts@gmail.com
% Copyright (C) 2015 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/.

% Loop through the distance arguments
for i = 1:2:nargin-1

    % If the second variable is not already numeric
    if ~isnumeric(varargin{i})

        % Parse it as a double
        varargin{i} = str2double(varargin{i});

    end
    
    % Log event
    Event(sprintf('Adjusting iso%s %0.2f mm', varargin{i+1}, varargin{i}));

    % Loop through delivery plan events
    for j = 1:size(plan.events, 1)

        % If the event specifies front jaw
        if strcmp(plan.events{j,2}, ['iso', varargin{i+1}]) 

            % Modify the event value
            plan.events{j,3} = plan.events{j,3} + varargin{i} / 10;

        end
    end
end