Sim() error in MATLAB app designer

I'm having an error while creating an app on app designer. The net.mat file was loaded into var and was accessed in y=sim(app.var,p). as shown:

classdef FAM < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure                     matlab.ui.Figure
        DiabeticRetinopathyDetectionLabel  matlab.ui.control.Label
        DevelopedbyFarhanHamzaLabel  matlab.ui.control.Label
        LoadimageButton              matlab.ui.control.Button
        UIAxes                       matlab.ui.control.UIAxes
        UIAxes2                      matlab.ui.control.UIAxes
        UIAxes3                      matlab.ui.control.UIAxes
        VesselsButton                matlab.ui.control.Button
        ExudatesButton               matlab.ui.control.Button
    end


    properties (Access = public)
        var = load('F:\Study\BME BOOKS\Semester 7\imaging\project2\Diabetic-Retinopathy-Detection-master\net.mat'); % specify the path to mat file
    end


    methods (Access = private)

        % Button pushed function: LoadimageButton
        function loadimage(app, event)
            
            global data;
            [FileName,PathName] = uigetfile('*.png;','select the image');  %reading the specifies types of the image
            dat=imread([PathName,FileName]);
            data=imresize(dat,[500 700]);  %reesizing the image into 500 700
            imshow(data,'Parent',app.UIAxes);   
  
                
        end

        % Button pushed function: VesselsButton
        function VesselsButtonPushed(app, event)
            global data;
            global bw2;
            global c;
            global mea2;
            global sd1;
            global numberOfCircles;
            greenchannel = data(:,:,2);    % green channel of the image

ginverse = imcomplement (greenchannel); % complementing green channel           
adahisteq = adapthisteq(ginverse);   %increasing the intensity of the inverse green channel for highlitening the blood vessel
threshold = 0.2;
BW = edge(adahisteq,'Canny',threshold);  %canny detection
h=imfill(BW,'holes'); % filling the holes
k=h-BW;

BW2 = bwpropfilt(logical(k),'Area',[7 12]); %taking out the clustered pixels of the specified range area
[l,numberOfCircles]= bwlabel(BW2);  % counting the number of clustered pixels

 
%extraction of blood vessel and haemorrhages
greenc = data(:,:,2);                          % Extract Green Channel
ginv = imcomplement (greenc);               % Complement the Green Channel
adahist = adapthisteq(ginv);
se = strel('ball',8,8);                     % Structuring Element
gopen = imopen(adahist,se);                 % Morphological Open
godisk = adahist - gopen;                   % Remove Optic Disk
 
medfilt = medfilt2(godisk);                 %2D Median Filter
background = imopen(medfilt,strel('disk',15));% imopen function
I2 = medfilt - background;                  % Remove Background
I3 = imadjust(I2);                          % Image Adjustment
 
level = graythresh(I3);                     % Gray Threshold
bw = im2bw(I3,level);                       % Binarization
bw1 = bwareaopen(bw, 30);
  
 [i,j]= size(bw1);
 c=0;
 for i=1:500
     for j=1:700
         if bw1(i,j)==1
             c=c+1;
         end
     end
 end
 imshow(bw1,'Parent',app.UIAxes2);   
  bw2=im2bw(bw1); %#ok<*IM2BW>
  
 mea2=mean2(bw2);
sd1=std2(bw2);
        end

        % Button pushed function: ExudatesButton
        function ExudatesButtonPushed(app, event)
            global data;
            global mea2;
            global sd1;
            global c;
            global numberOfCircles;
            %global net;
            
            g=data(:,:,2);
a=adapthisteq(g);
 
im= imadjust(a);
im2=im2bw(im,.9);
med=medfilt2(im2);
 
im3=imerode(med,strel('disk',10));
im4=imdilate(im3,strel('octagon',63));
 
 
im5=imimposemin(g,im4);
 
 
im6=g-im5;
im8=adapthisteq(im6);
im9=im2bw(im8);
med1=medfilt2(im9);
 
 
im10=imdilate(med1,strel('disk',40));
im12=med-im10;
im13=im2bw(im12);
BW2 = bwpropfilt(logical(im13),'Area',[0 1000]);

[k,l]= size(BW2);
c1=0;
 for k=1:500
     for l=1:700
         if im12(k,l)==1
             c1=c1+1;
         end
     end
 end
 imshow(BW2,'Parent',app.UIAxes3);   
 
  mea1=mean2(BW2);
sd2=std2(BW2);
 p=[c;c1;numberOfCircles;mea2;sd1;mea1;sd2];  % seven iput features
 y=sim('app.var',p);  %estimted 
o=round(y);
a1=[0 0 0 1];   % target values of the class 1
a2=[0 0 1 0];   % target values of the class 2
a3=[0 1 0 0];   % target values of the class 3
a4=[1 0 0 0];   % target values of the class 4
a11=a1.';  
a22=a2.';        %Transpose
a33=a3.';
a44=a4.';
if o == a11
    %disp('Normal eye');
    fig1 = uifigure;
message1 = {'Normal eye'};
uialert(fig1,message1,'Sucess',...
'Icon','Success');
else if o== a22
   %disp('Mild nonproliferative retinopathy');
   fig2 = uifigure;
message2 = {'Mild nonproliferative retinopathy'};
uialert(fig2,message2,'Sucess',...
'Icon','Success');
    else if o==a33
       % disp('moderate nonproliferative retinopathy');
         fig3 = uifigure;
message3 = {'moderate nonproliferative retinopathy'};
uialert(fig3,message3,'Sucess',...
'Icon','Success');
        else
           % disp('severe npdr');
            fig4 = uifigure;
message4 = {'severe npdr'};
uialert(fig4,message4,'Sucess',...
    'Icon','Success');
        end
 
        end
    end
        end
    end

    % App initialization and construction
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)

            % Create UIFigure
            app.UIFigure = uifigure;
            app.UIFigure.Position = [100 100 640 480];
            app.UIFigure.Name = 'UI Figure';

            % Create DiabeticRetinopathyDetectionLabel
            app.DiabeticRetinopathyDetectionLabel = uilabel(app.UIFigure);
            app.DiabeticRetinopathyDetectionLabel.HorizontalAlignment = 'center';
            app.DiabeticRetinopathyDetectionLabel.FontSize = 20;
            app.DiabeticRetinopathyDetectionLabel.FontWeight = 'bold';
            app.DiabeticRetinopathyDetectionLabel.Position = [168 425 305 34];
            app.DiabeticRetinopathyDetectionLabel.Text = 'Diabetic Retinopathy Detection';

            % Create DevelopedbyFarhanHamzaLabel
            app.DevelopedbyFarhanHamzaLabel = uilabel(app.UIFigure);
            app.DevelopedbyFarhanHamzaLabel.HorizontalAlignment = 'center';
            app.DevelopedbyFarhanHamzaLabel.FontWeight = 'bold';
            app.DevelopedbyFarhanHamzaLabel.Position = [230 404 181 22];
            app.DevelopedbyFarhanHamzaLabel.Text = 'Developed by Farhan & Hamza';

            % Create LoadimageButton
            app.LoadimageButton = uibutton(app.UIFigure, 'push');
            app.LoadimageButton.ButtonPushedFcn = createCallbackFcn(app, @loadimage, true);
            app.LoadimageButton.BackgroundColor = [0.302 0.749 0.9294];
            app.LoadimageButton.FontWeight = 'bold';
            app.LoadimageButton.Position = [55 372 100 22];
            app.LoadimageButton.Text = 'Load image';

            % Create UIAxes
            app.UIAxes = uiaxes(app.UIFigure);
            title(app.UIAxes, 'Orignal image')
            app.UIAxes.Position = [198 203 301 191];

            % Create UIAxes2
            app.UIAxes2 = uiaxes(app.UIFigure);
            title(app.UIAxes2, 'Vessels and Microaneuryms')
            app.UIAxes2.Position = [15 13 286 191];

            % Create UIAxes3
            app.UIAxes3 = uiaxes(app.UIFigure);
            title(app.UIAxes3, 'Exudates')
            app.UIAxes3.Position = [326 19 300 185];

            % Create VesselsButton
            app.VesselsButton = uibutton(app.UIFigure, 'push');
            app.VesselsButton.ButtonPushedFcn = createCallbackFcn(app, @VesselsButtonPushed, true);
            app.VesselsButton.Position = [55 319 100 22];
            app.VesselsButton.Text = 'Vessels';

            % Create ExudatesButton
            app.ExudatesButton = uibutton(app.UIFigure, 'push');
            app.ExudatesButton.ButtonPushedFcn = createCallbackFcn(app, @ExudatesButtonPushed, true);
            app.ExudatesButton.Position = [55 264 100 22];
            app.ExudatesButton.Text = 'Exudates';
        end
    end

    methods (Access = public)

        % Construct app
        function app = FAM

            % Create and configure components
            createComponents(app)

            % Register the app with App Designer
            registerApp(app, app.UIFigure)

            if nargout == 0
                clear app
            end
        end

        % Code that executes before app deletion
        function delete(app)

            % Delete UIFigure when app is deleted
            delete(app.UIFigure)
        end
    end
end

But I'm having this error:

Answer 1

[Kojiro Saito]

You need to input app.var without single quotations.

If you have saved your trained model (variable net),

save('net.mat', "net")

a

y=sim('app.var',p);  %estimted 

should be

y = sim(app.var.net, p);  %estimted 

Answer 2

[Steven Lord]

 y=sim('app.var',p);  %estimted 

This tries to call a version of the sim function that accepts a char vector as the first input. That's not what I believe you want. Determine the variable in the MAT-file that contains the object you want to simulate (I'll assume it's called theNet) and index into that variable stored in the property of your app.

y = sim(app.var.theNet, p);