Who can help me with this please?

I have this code

function radiobutton4_Callback(hObject, eventdata, handles)

a=handles.edit5;

%a=3; 

f=handles.edit2;

r1=handles.edit7;

r2=handles.edit8;

c=handles.edit9;

w=2*pi*f;

x=0:0.01:2*f;

syms x

y=a*sin((w*x));

Y=int(y,x);

z=(-1/(r1*c)).*Y

%z=(-r2/r1)*a*sin(w*x).*(1-exp(-x/(r2*c)));

%z=2*sin(2*pi/f*x+0); 

axes(handles.axes2)

plot(x,y,x,double(z),'g') 

grid on

And i need to graphic x,y and x,z in the same plot, but i got this error

Error using mupadmex
Error in MuPAD command: DOUBLE cannot convert the input expression into a double array.

If the input expression contains a symbolic variable, use the VPA function instead.

Error in sym/double (line 514)
        Xstr = mupadmex('symobj::double', S.s, 0);

Error in proyectoanaloga2>radiobutton4_Callback (line 219)
plot(x,y,x,double(z),'g')

Error in gui_mainfcn (line 96)
        feval(varargin{:});

Error in proyectoanaloga2 (line 42)
    gui_mainfcn(gui_State, varargin{:});

Error in
@(hObject,eventdata)proyectoanaloga2('radiobutton4_Callback',hObject,eventdata,guidata(hObject))

Error using figure
Error while evaluating uicontrol Callback

Answer 1

[Walter Roberson]

Your y is symbolic because it uses syms x. Your Y is symbolic because indefinite integration of y with respect to x gives a symbolic formula. Your z is a formula in that symbolic Y.

Your plot has plot(x,y,x,double(z)) which tries to construct two lines, one x vs y and the other x vs double(z). But all of those, x, y, and z, are symbolic with a free variable. They cannot be converted to numeric form to plot.

In order to do any plotting, you need to have definite values to evaluate at, and evaluate the symbolic expressions at those values.

You did have

x=0:0.01:2*f;

which looks at first like it provides definite values to x, but on the very next line you have

syms x

and that is equivalent to

x = sym('x');

complete with the implication of overwriting any existing value of x.

So... what you need is when you want to plot,

xn = 0:0.01:2*f;
yn = subs(y, x, xn);
zn = subs(z, x, xn);
plot(xn, yn, xn, zn, 'g');

[Andrés Felipe]

Thank you so much Walter, it works but i have the same plot with every variable inputs.

[Andrés Felipe]

I think is working now, I have a problem with the sawtooth function instead sin, it gives me this error

Error using proyectoanaloga2>radiobutton5_Callback (line 254) Input arguments must be 'double'.

Error in gui_mainfcn (line 96) feval(varargin{:});

Error in proyectoanaloga2 (line 42) gui_mainfcn(gui_State, varargin{:});

Error in @(hObject,eventdata)proyectoanaloga2('radiobutton5_Callback',hObject,eventdata,guidata(hObject))

Error while evaluating uicontrol Callback

[Walter Roberson]

I need to see the code inside the callback function.