Check for missing argument or incorrect argument data type in call to function 'sinc'.

I am trying to plot this problem:

However, I am encountering the error in the title whenever i try to plot it. Here is my code so far (I am still at a)):

function labactivity52()
[x,y]=meshgrid(-8:0.5:8);
z=sinc(sqrt((x.^2)+(y.^2)));
mesh(x,y,z), xlabel('x'), ylabel('y'), zlabel('z'), title('Surface Mesh Plot')
end

Whenever I try to run the function to see its 3D plot, I encounter this line:

Check for missing argument or incorrect argument data type in call to function 'sinc'.

Error in labactivity52 (line 3)

z=sinc(sqrt((x.^2)+(y.^2)));

What am I doing wrong? Is the given equation wrong?

Answer 1

[Walter Roberson]

The code works for me. You might have a sinc.m of your own that is interfering. Check

which -all sinc

You might see

/Applications/MATLAB_R2021a.app/toolbox/signal/signal/sinc.m
/Applications/MATLAB_R2021a.app/toolbox/signal/signal/@tall/sinc.m     % tall method
/Applications/MATLAB_R2021a.app/toolbox/symbolic/symbolic/@sym/sinc.m  % sym method

If you see your own function or a third-party toolbox function, then you might need to rename or delete something.

[Muhammad Baqir Sinarimbo]

I ran

which -all sinc

And this is the only one that showed up:

\MATLAB\R2020b\toolbox\symbolic\symbolic\@sym\sinc.m  % sym method

Is that what's supposed to come out? I notice that only one showed up in mine compared to your three.

[Muhammad Baqir Sinarimbo]

I apologize for commenting again but I opted to use the form (sin x)/x instead of sinc (x) and managed to get my code to work now. Thank you for taking the time out of your day to help me fix my problem!

[Walter Roberson]

Be careful: sinc() is not sin(x)/x, it is sin(pi*x)/(pi*x) in MATLAB.