How can I plot a user function in AppDesigner?

Well, I am developing an application that will allow to graph a signal either discrete or continuous, however, I do not know how I can read the function entered by the user in the text field to be able to graph it, I appreciate any help or advice.

Here I leave my code:

classdef app1 < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure                matlab.ui.Figure
        calculate               matlab.ui.control.Button
        FunctionEditFieldLabel  matlab.ui.control.Label
        functionf               matlab.ui.control.EditField
        SamplingSliderLabel     matlab.ui.control.Label
        slider                  matlab.ui.control.Slider
        Graph                   matlab.ui.control.UIAxes
        APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel  matlab.ui.control.Label
        tgswitch                matlab.ui.control.Switch
    end

    % Callbacks that handle component events
    methods (Access = private)

        % Button pushed function: calculate
        function calculateButtonPushed(app, event)
        %1. ASIGNAR VARIABLES A LOS CAMPOS DE ENTRADA
            t = -5 : 0.001 : 5;
            Fun = app.functionf.Value;
            Tipo = app.tgswitch.Value;
            Muestreo = app.slider;
            
        %2. DEFINIR VALORES DE SALIDA
            if strcmp(Tipo,'Continue')
                cla(app.Graph, 'reset');
                plot(app.Graph, Fun);
            else
                if strcmp(Tipo, 'Discret')
                    cla(app.Graph, 'reset');
                    stem(app.Graph, Fun);
                end
            end
                       
        end
    end

    % Component initialization
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)

            % Create UIFigure and hide until all components are created
            app.UIFigure = uifigure('Visible', 'off');
            app.UIFigure.Color = [0.9412 0.9412 0.9412];
            app.UIFigure.Position = [100 100 727 386];
            app.UIFigure.Name = 'UI Figure';

            % Create calculate
            app.calculate = uibutton(app.UIFigure, 'push');
            app.calculate.ButtonPushedFcn = createCallbackFcn(app, @calculateButtonPushed, true);
            app.calculate.Position = [289 25 152 22];
            app.calculate.Text = 'Calculate';

            % Create FunctionEditFieldLabel
            app.FunctionEditFieldLabel = uilabel(app.UIFigure);
            app.FunctionEditFieldLabel.HorizontalAlignment = 'right';
            app.FunctionEditFieldLabel.Position = [14 231 52 22];
            app.FunctionEditFieldLabel.Text = 'Function';

            % Create functionf
            app.functionf = uieditfield(app.UIFigure, 'text');
            app.functionf.Position = [81 231 205 22];

            % Create tgswitch
            app.tgswitch = uiswitch(app.UIFigure, 'slider');
            app.tgswitch.Items = {'Continue', 'Discret'};
            app.tgswitch.Position = [127 170 45 20];
            app.tgswitch.Value = 'Continue';

            % Create SamplingSliderLabel
            app.SamplingSliderLabel = uilabel(app.UIFigure);
            app.SamplingSliderLabel.HorizontalAlignment = 'right';
            app.SamplingSliderLabel.Position = [14 115 56 22];
            app.SamplingSliderLabel.Text = 'Sampling';

            % Create slider
            app.slider = uislider(app.UIFigure);
            app.slider.Position = [91 124 203 3];

            % Create Graph
            app.Graph = uiaxes(app.UIFigure);
            title(app.Graph, 'Signal')
            xlabel(app.Graph, 'X')
            ylabel(app.Graph, 'Y')
            app.Graph.Position = [304 70 410 227];

            % Create APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel
            app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel = uilabel(app.UIFigure);
            app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.HorizontalAlignment = 'center';
            app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.FontSize = 15;
            app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.FontWeight = 'bold';
            app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.Position = [139.5 330 451 22];
            app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.Text = 'APPLICATION PROYECT (DISCRET AND CONTINUE SIGNAL)';

            % Show the figure after all components are created
            app.UIFigure.Visible = 'on';
        end
    end

    % App creation and deletion
    methods (Access = public)

        % Construct app
        function app = app1

            % Create UIFigure and 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

[Mario Malic]

What is the function user types in?

Are you plotting functions like ax+b = c, where you are varying paramers (a, b and c) and domain with slider? Or functions can be anything what user wants.

You can write a function similar to what you did.

 functionf matlab.ui.control.EditField

If this is text field then you can check str2func function, if not, then you can update only parameters using values from slider in your plot function.

You can add this function below to every component callback that affects the plot so it can update itself as you change the value. You should create plotfun, sliderval1, sliderval2 as public properties.

Disclaimer: Not sure if this is a good practice

% if you declare public properties, you don't have to send them as input arguments
function calculatestuff(app) 
    % Calculation code
    % Plot code
end

[Andres David Mestizo Valencia]

Okay, first I appreciate your prompt response, second, the type of function to work with are continuous functions (trigonometric, exponential, algebraic, etc).

The slider is needed to vary the sampling of a graph in case the user wants to observe it as a discrete function.

Finally, I would like to ask you how I can rate your answer to give you points, because it is the first time that I ask here :P

[Mario Malic]

I haven't used this function before, so I am just giving you a hint. If I was able to provide a functional code, I would have post my comment as an answer, for which you could vote/accept.

Once you're finished you can put parts of relevant code (and accept your own answer) so the other users can learn from it in case someone ends up with a similar issue.

[Andres David Mestizo Valencia]

In spite of everything, I really appreciate your collaboration, and I will continue trying to solve this problem.

Have a nice day

[Andres David Mestizo Valencia]

I found the answer, and i leave the answer here:

classdef app1 < matlab.apps.AppBase

% Properties that correspond to app components

properties (Access = public)

UIFigure matlab.ui.Figure

calculate matlab.ui.control.Button

FunctionEditFieldLabel matlab.ui.control.Label

functionf matlab.ui.control.EditField

tgswitch matlab.ui.control.Switch

Graph matlab.ui.control.UIAxes

APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel matlab.ui.control.Label

SamplingSpinnerLabel matlab.ui.control.Label

SamplingSpinner matlab.ui.control.Spinner

end

% Callbacks that handle component events

methods (Access = private)

% Button pushed function: calculate

function calculateButtonPushed(app, event)

%1. ASIGNAR VARIABLES A LOS CAMPOS DE ENTRADA

syms x;

Fun = app.functionf.Value;

Fun = strcat('@', '(x)', string(Fun));

y = str2func(Fun);

Tipo = app.tgswitch.Value;

Muestreo = app.SamplingSpinner.Value;

%2. DEFINIR VALORES DE SALIDA

t1 = -100:0.001:100;

if strcmp(Tipo,'Continue')

cla(app.Graph, 'reset');

plot(app.Graph, t1,y(t1), "black");

grid on;

close Figure 1;

else

if strcmp(Tipo, 'Discret')

t2 = -100: Muestreo: 100;

cla(app.Graph, 'reset');

stem(app.Graph,t2,y(t2), "filled", "black" ,'LineWidth',1.5);

grid on;

close Figure 1;

end

end

end

end

% Component initialization

methods (Access = private)

% Create UIFigure and components

function createComponents(app)

% Create UIFigure and hide until all components are created

app.UIFigure = uifigure('Visible', 'off');

app.UIFigure.Color = [0.9412 0.9412 0.9412];

app.UIFigure.Position = [100 100 937 665];

app.UIFigure.Name = 'UI Figure';

% Create calculate

app.calculate = uibutton(app.UIFigure, 'push');

app.calculate.ButtonPushedFcn = createCallbackFcn(app, @calculateButtonPushed, true);

app.calculate.Position = [394 18 152 22];

app.calculate.Text = 'Calculate';

% Create FunctionEditFieldLabel

app.FunctionEditFieldLabel = uilabel(app.UIFigure);

app.FunctionEditFieldLabel.HorizontalAlignment = 'right';

app.FunctionEditFieldLabel.Position = [74 551 52 22];

app.FunctionEditFieldLabel.Text = 'Function';

% Create functionf

app.functionf = uieditfield(app.UIFigure, 'text');

app.functionf.Position = [141 551 205 22];

% Create tgswitch

app.tgswitch = uiswitch(app.UIFigure, 'slider');

app.tgswitch.Items = {'Continue', 'Discret'};

app.tgswitch.Position = [480 552 45 20];

app.tgswitch.Value = 'Continue';

% Create Graph

app.Graph = uiaxes(app.UIFigure);

title(app.Graph, 'Signal')

xlabel(app.Graph, 'X')

ylabel(app.Graph, 'Y')

app.Graph.XGrid = 'on';

app.Graph.YGrid = 'on';

app.Graph.Position = [47 60 851 463];

% Create APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel

app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel = uilabel(app.UIFigure);

app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.HorizontalAlignment = 'center';

app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.FontSize = 15;

app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.FontWeight = 'bold';

app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.Position = [244 614 451 22];

app.APPLICATIONPROYECTDISCRETANDCONTINUESIGNALLabel.Text = 'APPLICATION PROYECT (DISCRET AND CONTINUE SIGNAL)';

% Create SamplingSpinnerLabel

app.SamplingSpinnerLabel = uilabel(app.UIFigure);

app.SamplingSpinnerLabel.HorizontalAlignment = 'right';

app.SamplingSpinnerLabel.Position = [671 551 56 22];

app.SamplingSpinnerLabel.Text = 'Sampling';

% Create SamplingSpinner

app.SamplingSpinner = uispinner(app.UIFigure);

app.SamplingSpinner.Step = 0.5;

app.SamplingSpinner.Limits = [0 30];

app.SamplingSpinner.Position = [742 551 100 22];

app.SamplingSpinner.Value = 0.5;

% Show the figure after all components are created

app.UIFigure.Visible = 'on';

end

end

% App creation and deletion

methods (Access = public)

% Construct app

function app = app1

% Create UIFigure and 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

[Mario Malic]

You can put your answer in the answers section and accept it yourself, It's better to attach it as a file, since the code is long.

[Sourabh Kondapaka]

Hi @Andres David Mestizo Valencia,

As @Mario Malic suggested, it would be better if you post your comment as an answer and accept it, as it would be easy for others who find this question.