DanDoherty
Published © GPL3+

Function Graphing with MATLAB & Sparkfun Digital Sandbox

This project uses the Arduino-based Sparkfun Digital Sandbox as the controller for an interactive function graphing game.

BeginnerProtip3 hours587
Function Graphing with MATLAB & Sparkfun Digital Sandbox

Things used in this project

Hardware components

SparkFun Digital Sandbox
SparkFun Digital Sandbox
×1

Software apps and online services

MATLAB
MATLAB

Story

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Code

Helper Functions

MATLAB
Here are the main helper functions that represent the logic of the game. To view all of the code, please go to the File Exchange link provided above.
% This function displays the key points for the graph selected by the user. 
function Grapher(app, index)
    if strcmp(app.graphChoices(index),'Linear 1')
        hold(app.UIAxes, 'off');
        plot([0 .2 .4 .6 .8 1],[0 .2 .4 .6 .8 1],'ro','Parent',app.UIAxes);
        app.XPoints = [0 0.2 0.4 0.6 0.8 1];
        app.YPoints = [0 0.2 0.4 0.6 0.8 1];
        hold(app.UIAxes,'on');
        app.UIAxes.Title.String = 'Unknown Function';
        app.sliderIndicator = line(0,0,'Marker','o','MarkerFaceColor',[1 0 0],'Parent', app.UIAxes);
        drawnow limitrate;
    elseif strcmp(app.graphChoices(index),'Linear 2')
        hold(app.UIAxes, 'off');
        plot([0 .2 .4 .6 .8 1], [1 .8 .6 .4 .2 0], 'ro', 'Parent', app.UIAxes);
        app.XPoints = [0 0.2 0.4 0.6 0.8 1];
        app.YPoints = [1 0.8 0.6 0.4 0.2 0];
        hold(app.UIAxes,'on');
        app.UIAxes.Title.String = 'Unknown Function';
        app.sliderIndicator = line(0,0,'Marker','o','MarkerFaceColor',[1 0 0],'Parent', app.UIAxes);
        drawnow limitrate;
    elseif strcmp(app.graphChoices(index),'Sinusoid 1')
        hold(app.UIAxes,'off')
        plot(round(0:pi/2:2*pi,1), round(sin(0:pi/2:2*pi),1), 'ro','Parent', app.UIAxes)
        app.XPoints = 0:pi/2:2*pi;
        app.YPoints = round(sin(0:pi/2:2*pi));
        hold(app.UIAxes,'on');
        app.UIAxes.Title.String = 'Unknown Function';
        app.sliderIndicator = line(0,0,'Marker','o','MarkerFaceColor',[1 0 0],'Parent', app.UIAxes);
        drawnow limitrate;
    elseif strcmp(app.graphChoices(index),'Sinusoid 2')
        hold(app.UIAxes,'off')
        plot(round(0:pi/2:2*pi,1), round(cos(0:pi/2:2*pi),1), 'ro','Parent', app.UIAxes)
        app.XPoints = 0:pi/2:2*pi;
        app.YPoints = round(cos(0:pi/2:2*pi),1);
        hold(app.UIAxes,'on');
        app.UIAxes.Title.String = 'Unknown Function';
        app.sliderIndicator = line(0,0,'Marker','o','MarkerFaceColor',[1 0 0],'Parent', app.UIAxes);
        drawnow limitrate;
    end
end

% This function determines whether the user selects a correct point or not and contains function calls to a majority of the game's main operations.
function CheckPts(app, index)
    app.ButtonIsPressed = readDigitalPin(app.a, app.buttonPin);
    if app.ButtonIsPressed && strcmp(app.graphChoices(index), 'Linear 1')
        if find(app.XPoints == app.sliderIndicator.XData) == (find(app.YPoints == app.sliderIndicator.YData))
            correctAnswer(app);
            progressGraph(app, index);
        else
            wrongAnswer(app);
        end
    elseif app.ButtonIsPressed && strcmp(app.graphChoices(index), 'Linear 2')
        if find(app.XPoints == app.sliderIndicator.XData) == (find(app.YPoints == app.sliderIndicator.YData))
            correctAnswer(app);
            progressGraph(app, index);
        else
            wrongAnswer(app);
        end
    elseif app.ButtonIsPressed && strcmp(app.graphChoices(index), 'Sinusoid 1')
        if any(find(app.XPoints == app.sliderIndicator.XData) == (find(app.YPoints == app.sliderIndicator.YData)))
            correctAnswer(app);
            progressGraph(app, index);
        else
            wrongAnswer(app);
        end
    elseif app.ButtonIsPressed && strcmp(app.graphChoices(index), 'Sinusoid 2')
        if any(find(app.XPoints == app.sliderIndicator.XData) == (find(app.YPoints == app.sliderIndicator.YData)))
            correctAnswer(app);
            progressGraph(app, index);
        else
            wrongAnswer(app);
        end
    end
end

% This function handles the case where the user selects a correct point. It keeps a log of all of the correct points that they selected on the current graph. Additionally, it handles the case where they already pressed a point.
function correctAnswer(app)
    if ~isempty(app.pointsPressed) && ismember([app.sliderIndicator.XData, app.sliderIndicator.YData], app.pointsPressed,'rows')
        app.Lamp.Color = 'yellow';
        app.TextArea.Value = 'You already pressed that! Try something else.';
    else
        writeDigitalPin(app.a, app.correctPin, 1);
        pause(.5)
        writeDigitalPin(app.a, app.correctPin, 0);
        app.Lamp.Color = 'green';
        app.numCorrect = app.numCorrect + 1;
        app.pointsPressed(app.numCorrect,1) = app.sliderIndicator.XData;
        app.pointsPressed(app.numCorrect,2) = app.sliderIndicator.YData;
        plot(round(app.sliderIndicator.XData,1), app.sliderIndicator.YData, 'go', 'Parent', app.UIAxes);
        hold(app.UIAxes,'on')
        app.TextArea.Value = 'Good job! Keep it up!';
    end
end

% This function handles the case where the user selects an incorrect point. 
function wrongAnswer(app)
    writeDigitalPin(app.a, app.wrongPin, 1);
    pause(.5)
    writeDigitalPin(app.a, app.wrongPin, 0);
    app.Lamp.Color = 'red';
    app.TextArea.Value = 'Oh no! That is not correct.  You should try one of the highlighted points';
end

% This function creates a graph of the function that the user is learning up to the maximum X point that they correctly selected. 
function progressGraph(app,index)
    if strcmp(app.graphChoices(index), 'Linear 1')
        plot(0:0.2:app.sliderIndicator.XData, 0:0.2:app.sliderIndicator.YData, 'Color', [0 1 0], 'Parent', app.UIAxes)
        hold(app.UIAxes,'on')
    elseif strcmp(app.graphChoices(index), 'Linear 2')
        plot(0:0.2:app.sliderIndicator.XData, 1:-0.2:app.sliderIndicator.YData, 'Color', [0 1 0], 'Parent', app.UIAxes)
        hold(app.UIAxes,'on')
    elseif strcmp(app.graphChoices(index), 'Sinusoid 1')
        plot(0:pi/20:app.sliderIndicator.XData, sin(0:pi/20:app.sliderIndicator.XData), 'Color', [0 1 0], 'Parent', app.UIAxes)
        hold(app.UIAxes,'on')
    elseif strcmp(app.graphChoices(index), 'Sinusoid 2')
        plot(0:pi/20:app.sliderIndicator.XData, cos(0:pi/20:app.sliderIndicator.XData), 'Color', [0 1 0], 'Parent', app.UIAxes)
        hold(app.UIAxes,'on')
    end
    if length(app.pointsPressed) == length(app.XPoints)
        GraphComplete(app,index);
        app.pointsPressed = [];
    end
end

function ButtonButtonPushed(app)
% Determine what graphs the user wants to learn
  determineMode(app);
  
% Don't start the game until the on/off switch (slide switch) is in the 'ON' position
  while 1
      app.SwitchIsOn = readDigitalPin(app.a, app.switchPin);
      if app.SwitchIsOn
          break
      end
  end
  
% For each option that they selected, graph the key points of the function  
  for k = 1:length(app.graphChoices)
      Grapher(app, k);
      while true
% If they ever change the position of the on/off switch, end the game
          app.SwitchIsOn = readDigitalPin(app.a, app.switchPin);
          if ~app.SwitchIsOn
              break;
          else
% Determine the x and y coordinates for the user's cursor and make sure the 
% y-coordinate is within the range of the Y-Axis
              app.x = round(readVoltage(app.a, app.slidePin) / app.slideMax,1);
              app.y = round(readVoltage(app.a, app.photoPin) / app.photoMax, 1);
              if app.y >= 1
                  app.y = 1;
              end
              
% If they are currently learning a Sinusoid, digitize their raw inputs
              if strcmp(app.graphChoices(k), 'Sinusoid 1') || strcmp(app.graphChoices(k), 'Sinusoid 2')
                  SinusoidScaler(app);
              end
              
% Update the position of the user's cursor in the game and check if they have pressed a correct point
              app.sliderIndicator.XData = app.x;
              app.sliderIndicator.YData = app.y;
              drawnow limitrate;
              CheckPts(app, k);
              
% If they pressed all of the necessary points, reset the graphing axes and move on the next function that they want to learn
              if isempty(app.pointsPressed) && app.numCorrect ~= 0
                  app.numCorrect = 0;
                  app.TextArea.Value = '';
                  app.UIAxes.Title.String = ''; 
                  app.Lamp.Color = [1 1 1];
                  break;
              end
          end                
      end
  end
% If they learned all of the functions, show them the dancing function man
  if length(app.graphChoices) == 4
      app.UIAxes.Title.String = 'The Function Dance!';
      app.TextArea.Value = 'Check out this dance of the functions that you learned!';
      pause(1);
    
% Create the dancing man's body 
      app.faceX = app.radiusOfFace*cosd(0:360);
      app.faceY = app.radiusOfFace*sind(0:360) +3;
      app.bodyX = 0*ones(1,5);
      app.bodyY = app.radiusOfFace+1:-1:app.radiusOfFace-3;
      app.leftLegX = app.radiusOfFace-1:-1:app.radiusOfFace-4;
      app.leftLegY = app.radiusOfFace-3:-1:app.radiusOfFace-6; 
      app.rightLegX = app.radiusOfFace-1:1:app.radiusOfFace+2;
      app.rightLegY = app.radiusOfFace-3:-1:app.radiusOfFace-6;   
      app.handX = -pi:pi/30:pi;
      hold(app.UIAxes,'off')
% Show them the dance for Y = X and Y = -X
      for i = 1:2
          app.UIAxes.Title.String = 'Y = -X and Y = X';
          app.TextArea.Value = 'Check out what Y = X and Y = -X look like!';
          plot(app.faceX, app.faceY,'b', 'Parent', app.UIAxes)
          hold(app.UIAxes, 'on');
          plot(app.bodyX,app.bodyY,'b', 'Parent', app.UIAxes)
          plot(app.leftLegX,app.leftLegY,'b', 'Parent', app.UIAxes)
          plot(app.rightLegX,app.rightLegY,'b', 'Parent', app.UIAxes)
          
          hold(app.UIAxes, 'on');
          app.handY = abs(app.handX);
          plot(app.handX, app.handY,'b', 'Parent', app.UIAxes)
          hold(app.UIAxes,'off')
          pause(1)
          
          plot(app.faceX, app.faceY,'b','Parent', app.UIAxes )
          hold(app.UIAxes, 'on');
          plot(app.bodyX,app.bodyY,'b', 'Parent', app.UIAxes)
          plot(app.leftLegX,app.leftLegY,'b', 'Parent', app.UIAxes)
          plot(app.rightLegX,app.rightLegY,'b', 'Parent', app.UIAxes)
          
          app.handY = -abs(app.handX);
          plot(app.handX, app.handY,'b', 'Parent', app.UIAxes)
          
          pause(1)
          hold(app.UIAxes,'off')  
      end
% Show them the dance for Y = sin(x) and Y = cos(x)
      for i = 1:2
          app.UIAxes.Title.String = 'Y = sin(x) and Y= cos(x)';
          app.TextArea.Value = 'Check out what Y = sin(x) and Y = cos(x) look like!';
          plot(app.faceX, app.faceY,'b', 'Parent', app.UIAxes)
          hold(app.UIAxes, 'on');
          plot(app.bodyX,app.bodyY,'b', 'Parent', app.UIAxes)
          plot(app.leftLegX,app.leftLegY,'b', 'Parent', app.UIAxes)
          plot(app.rightLegX,app.rightLegY,'b', 'Parent', app.UIAxes)
          
          app.handY = sin(app.handX);
          plot(app.handX, app.handY,'b', 'Parent', app.UIAxes)
          hold(app.UIAxes,'off')
          pause(1)

          plot(app.faceX, app.faceY,'b', 'Parent', app.UIAxes)
          hold(app.UIAxes, 'on');
          plot(app.bodyX,app.bodyY,'b', 'Parent', app.UIAxes)
          plot(app.leftLegX,app.leftLegY,'b', 'Parent', app.UIAxes)
          plot(app.rightLegX,app.rightLegY,'b', 'Parent', app.UIAxes)
          
          app.handY = -sin(app.handX);
          plot(app.handX, app.handY,'b', 'Parent', app.UIAxes)
          
          pause(1);
          hold(app.UIAxes,'off');
      end
% Once the man finishes dancing, the game is over until they select another mode
      app.TextArea.Value = 'Thanks for playing!';
  end

Credits

DanDoherty

DanDoherty

5 projects • 4 followers

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