how to plot z=9-sqrt(x^2+y^2) inside the cylinder r=2?

clear all;
syms x y;
xlabel('x');
ylabel('y');
zlabel('z');
 
[x,y] = meshgrid(-10:1:10,-10:1:10);
y=9-sqrt(x.^2+y.^2);
surf(x,y,x);
view([10 10 10]);

[madhan ravi]

Use one approach either symbolic or numerical don't mix them together.

Answer 1

[madhan ravi]

syms x y
ezsurf(9-sqrt(x.^2+y.^2));
axis([-10 10 -10 10 -10 10])   % you can limit the range here
hold on
fimplicit3(x^2+y^2==2^2)
view([10 10 10]);

[Carter Pennington]

wait it needs to be in spherical form

Answer 2

[KSSV]

% Mesh a cylinder
R = 2 ;   % radius 
h = 2. ;  % height 

m = 50 ;
n = 50 ;

% Discretizing the Height and Angle of the cylinder
nH = linspace(0,h,m) ;
nT = linspace(0,360.,n)*pi/180 ;
[H, T] = meshgrid(nH,nT) ;
% Convert grid to cylindrical coordintes
X = R*cos(T); 
Y = R*sin(T);
Z = H ;
%
[x,y] = meshgrid(-R:0.1:R,-R:0.1:R);
z=h-sqrt(x.^2+y.^2);
surf(x,y,z);
hold on
surf(X,Y,Z)
xlabel('x');
ylabel('y');
zlabel('z');

view([10 10 10]);

YOu have to play with the second equation, so that it lies inside cylinder.