How to do correctly DFT of the x,y data?

Dear all,

I have coordinates x_okoli,y_okoli and I would like to show output, but this error appears:

Undefined function 'fftgui' for input arguments of type 'double'.

Error in mesh_okoli (line 96) fftgui(m)

This is my code: x = x_okoli(1,1); y = y_okoli(1,1); z = x + i*y; A = abs(z); fi = angle(z); %fi2 = atan2(imag(z),real(z)) f = 50; omega = 2*pi*f; m = A*cos(omega*x+fi)+A*i*sin(omega*y+fi); figure(7) fftgui(m)

Thank you for your answers.

[John D'Errico]

The error you are getting is that fftgui is not found. You would apparently need to have downloaded it from here:

https://www.mathworks.com/matlabcentral/fileexchange/4822-using-numerical-computing-with-matlab-in-the-classroom/content/fftgui.m

[Veronika]

Thank you.

[Veronika]

For one coordinate value it works, but for all the coordinates it says this error:

Error using  * 
Inner matrix dimensions must agree.

Error in mesh_okoli (line 94)
m = A*cos(omega*x+fi)+A*i*sin(omega*y+fi);

This is my code:

for x = x_okoli(:,1);
    y = y_okoli(:,1);
z = x + i*y;
A = abs(z);
fi = angle(z);
%fi2 = atan2(imag(z),real(z))
f = 50;
omega = 2*pi*f;
m = A*cos(omega*x+fi)+A*i*sin(omega*y+fi);
figure(7)
fftgui(m)
end

x_okoli and y_okoli is my coordinates. I attach my code too. Can you help me and tell where is the mistake?

Thank you for your answer.

Answer 1

[Image Analyst]

Regarding

m = A*cos(omega*x+fi)+A*i*sin(omega*y+fi);

either look in the debugger (like most people) or add these lines before that line

whos A
whos i
whos omega
whos y
whos fi

First read this link and then, in the editor in MATLAB, type control a (to select all) and control i (to properly indent) then copy, then paste your answer back here.

Chances are, one of those is an array and you were expecting a scalar, so it's doing a matrix multiply instead of a scalar or element-by-element multiply.

[Veronika]

%%Mesh okolí
for x = x_okoli(:,1);
    y = y_okoli(:,1);
z = x + i*y;
A = abs(z);
fi = angle(z);
%fi2 = atan2(imag(z),real(z))
f = 50;
omega = 2*pi*f;
m = A*cos(omega*x+fi)+A*i*sin(omega*y+fi);
figure(7)
fftgui(m)
end

I attach whole code.