Question

I'm stuck again in MATLAB. Can anyone help me out? I'll post the problem below.

Answer 1

What I did so far.....
P.S. I'm new to Matlab so please take it easy on me :P

Answer 2

That's a good start, the error you got is due to a wrong multiplication of arrays.
In Matlab we use .* instead of * in element-by-element multiplication.
I would use something along these lines:

s=linspace(0,pi,100)
t=linspace(0,2*pi,200)
[s,t]=meshgrid(s,t);
r=5+sin(10*s+5*t);

y=r.*sin(s).*sin(t);
x=r.*cos(s).*sin(t);
z=r.*cos(t);

surf(x,y,z)

Answer 3

oh okay thank you so much!
here's my output:

Answer 4

I hope they're not expecting a sphere, cause that looks nothing like it :P
Also they should have given you the range of s and t. Above, I put randomly 0<t<2*pi and 0<s<pi

Answer 5

Don't worry, they are not asking for sphere because I already made a sphere on the previous question :P This one we have to rotate on the xy plane so it will look like a flower (see image below)

this is the code that I used, just posting it here for future reference:
syms s t
r= 5 + sin(10.*s+5.*t);
y= r.*sin(s).*sin(t);
x= r.*cos(s).*sin(t);
z=r.*cos(t);

figure
ezsurf(x,y,z, [0, 2*pi, 0, pi])

I based it from what you did ;) Thanks again!

Answer 6

You're much welcome =)