how can i represent 3d surface(conical surface) by using surface vector function

xw=10;
qg=2*pi;
qw=1;
lw=0:pi/12:pi/2;

x=(xw+qw*sin(lw))*cos(qg);
y=(xw+qw*sin(lw))*sin(qg);
z= qw*(1-cos(lw));

hi everyone ,

i want to represent 3d surface by using those vector equations(equation should be represent conical surface) but i couldnt achieve yet. i use "meshgrid" and "surf" command but i couldnt do it.

Can anybody help me with these problem ?

Answer 1

[Roger Stafford]

You should be using the results of meshgrid to calculate Z so that it will be a matrix, not a vector. As near as I can make out, your conical vertex is located at a point (3*cot(pi/5),0,0). Try this:

fic = pi/5;
u = linspace(0,8);
q = linspace(0,2*pi);
[U,Q] = meshgrid(u,q);
X = 3*cot(fic)-(U.*cos(Q))*cos(fic);
Y = (U.*sin(Q))*cos(fic);
Z = U*sin(fic);
surf(X,Y,Z)

I may not have guessed correctly as to your intended cone location, orientation, or angle, but this code should give some pointers about how to obtain the result you desire.

[can özbaran]

it worked thank you so much :)

Answer 2

[can özbaran]

ro=3;
fic=pi/5;
u=linspace(0,8);
Q=linspace(0,pi/2);
x=ro*cot(fic)-u*cos(fic);
y=u*sin(fic).*sin(Q);

[X,Y]=meshgrid(x,y);

Z=u.*sin(fic).*cos(Q);

figure
surf(X,Y,Z)
xlabel('x axis');
ylabel('y axis');
zlabel('z axis');

i changed the formulation and applied into code when i running the code,i am taking an error message like

Z must be a matrix, not a scalar or vector.