tutorial.m

function tutorial
%TUTORIAL An interactive tutorial to teach people how to use basic MATLAB
%functionality
%   The user just needs to execute the function and answer the questions by
%   filling in MATLAB commands. First a brief background on each topic is
%   provided, followed by a question. The function waits for input from the
%   user and checks if the answer is correct. This is done in form of
%   string comparison.
%   
%   The background, questions and possible answers are all stored in a cell
%   inside the 'tasks.mat' file. The progress for the questions is saved in
%   the 'progress.mat' file and multiple users are supported. The
%   progress.mat file is not part of the git repository so that the
%   progress is not erased when pull updates from the server.

    % Loading the matlab structure that contains the tasks for the tutorial
    load tasks.mat
    load messages.mat
    gong = load('gong');
    handel = load('handel');
    
    % Checking to see if a progress file exists. If not, then it will be
    % created later on
    if exist('progress.mat','file')
        load progress.mat
    else
        progress = struct;
    end
    
    % Getting the username, for storing progress of a student
    user = input('Please provide your username (no numbers please): ','s');
    
    courses = {'Robotics','Optimisation','System identification'};
    figure('Position',[300 300 200 100],'Name','Selection','MenuBar','none');
    parentpanel = uipanel('Units','pixels','Title','Choose your course','Position',[5 5 190 90]);
    lbs = uicontrol ('Parent',parentpanel,'Style','popupmenu','String',courses,'Units','Pixels','Position',[4 5 180 60]);
    uicontrol('Style','pushbutton','String','Done','Position',[50 10 100 30],'Callback',@hDoneCallback);
    uiwait
    course = courses(get(lbs,'Value'));
    close
    
    users = fieldnames(progress);
    sound(gong.y,gong.Fs)
    
    % Getting a list of questions
    questions = fieldnames(tasks);
    
    % Checking if the user exists. If not, then create her
    if ~ismember(user,users)
        progress.(user) = 1;
    end
    level = progress.(user);
    repeat = 0;
    
    % Loop over all the questions
    while level<=length(questions)
        task = tasks.(questions{level});
        if ismember(lower(course),task.courses) || ismember('all',task.courses)
            if ~repeat
                fprintf('Background:\n=====================================================\n\n')
                % Print the background information
                fprintf([task.background,'\n'])
                fprintf('=====================================================\n\n')
            end

            % Providing the option to go back one question and practise
            % again
            fprintf('Type ''previous'' for going one question back, ''background'' for reading the background again, or exit to leave the tutorial\n\n')

            % Print the question and wait for input from the user
            answer = input(['Question ',num2str(level),':\n\n',task.question,': '],'s');

            % Going back a level, if the user wants to
            switch answer
                case 'previous'
                    level = max(level-1,1);
                    continue
                case 'exit'
                    return
                case 'background'
                    repeat = 0;
                    continue
                case 'ronco'
                    level = level+1;
                    continue
            end

            % Pre-evaluation events, in case some workspace preparation is
            % needed
            for command=task.preeval
                try
                    eval([command{:},';'])
                catch e
                    fprintf(2,'MATLAB error message:\n%s \n',e.message);
                    fname=e.stack.name; 
                    if ~(strcmp(fname,'tutorial')==1)
                        l=e.stack.line;
                        fprintf(2,'Error in %s.m file, at line %d\n',fname, l);
                    end
                end
            end

            switch task.type
                case 'string'
                    % Check if the input matches the possible answers registered. If
                    % yes, then print a congratulatory message and update the progress.
                    % If not then ask the question again
                    correct = find(ismember(task.evaluation, answer));
                case 'commands'
                    % Do several evaluations to check if the code is behaving
                    % the way it should. The evaluations should all give a 1 if
                    % they are successful or 0 if they are not. If a 0 is
                    % generated the evaluation sequence is stopping.
                    correct = 1;
                    command = 1;
                    try
                        eval(answer)
                    catch e
                        fprintf(2,'MATLAB error message:\n%s \n',e.message);
                        fname=e.stack.name;
                        if ~(strcmp(fname,'tutorial')==1)
                            l=e.stack.line;
                            fprintf(2,'Error in %s.m file, at line %d\n',fname, l);
                        end
                        correct = 0;
                    end
                    while (command<=length(task.evaluation) && correct>0)
                        try
                            correct = eval(task.evaluation{command})*correct;
                            command = command+1;
                        catch e
                            fprintf(2,'MATLAB error message:\n%s \n',e.message);
                            fname=e.stack.name; 
                            if ~(strcmp(fname,'tutorial')==1)
                                l=e.stack.line;
                                fprintf(2,'Error in %s.m file, at line %d\n',fname, l);
                            end
                            correct = 0;
                            break
                        end
                    end
            end

            % Post-evaluation events, in case some cleaning-up is required
            for command=task.posteval
                try
                    eval([command{:},';'])
                catch e
                    fprintf(2,'MATLAB error message:\n%s \n',e.message);
                    fname=e.stack.name; 
                    if ~(strcmp(fname,'tutorial')==1)
                        l=e.stack.line;
                        fprintf(2,'Error in %s.m file, at line %d\n',fname, l);
                    end  
                end
            end

            if all(correct)
                cmessage = randperm(numel(congrats)); %#ok<USENS> Loaded at the beginning of the function
                fprintf([congrats{cmessage(1)},'\n\nPress enter to continue\n\n'])
                level = level+1;
                progress.(user) = level;
                save('progress.mat','progress')
                repeat = 0;
                pause
            else
                rmessage = randperm(numel(retry)); %#ok<USENS> Loaded at the beginning of the function
                fprintf([retry{rmessage(1)},'\n\n'])
                repeat = 1;
            end
        else
            level = level+1;
            repeat = 0;
        end
    end
    
    % When all questions are completed, then congratulate the user and
    % direct her to the github repository.
    sound(handel.y,handel.Fs)
    fprintf(['\n\nWell done! You have completed all the questions!\nYou are now ready to dive deeper into MATLAB and become a guru one day!\n',...
            'We hope you enjoyed. You can find updates of this tutorial on our github repository https://www.github.com/tassos/matlab_tutorial\n\n'])
end

%% Resume
% Callback to resume operation after user has made her choices
function hDoneCallback(~, ~)
    uiresume
end