Getting Error while using Transparency to object (alpha)

I get the following error ("Unable to use a value of type matlab.graphics.chart.primitive. Surface as an index. alpha(s,.2)") message sometimes and I don't know why?

r = 50;        % The radius of the circular plan given in Km
r = km2deg(r);      % Convert to Degree
[X,Y,Z] = cylinder(r);
p0=[48,278,0];    % base location in Degrees

X=X+p0(1); Y=Y+p0(2); Z=Z+p0(3);  %translate cylinder to new location

h = 80;
Z = Z*h;

subplot(2, 2, [1 3])
 s = surf(Y,X,Z,'FaceColor','#80B3FF', 'EdgeColor','none');
%     view(43,180);
%     camdolly(0,0,0)
    alpha(s,.2)

I am using MATLAB R2022a on a macOS ventura 13.1 machine.

Answer 1

[Voss]

You have a variable called "alpha" in your workspace, which is preventing you from running the "alpha" function.

You should remove the variable by running the command

clear alpha

on the command line, and then run your script again.

[Telema Harry]

I did not think of that. Thank you @Voss.