Plot with 2 parameters

syms r teta x y

teta= -90: 0.1: 90;

r= 0.5:0.1:1.5;

x=sind(teta).*r;

y=cosd(teta).*r;

plot(x,y)

that my code, I want to see a plot like half disc with a hole but it doesnt work :(

Answer 1

[Alan Stevens]

Do you mean something like this:

theta = -90:90;
ri = 0.5; ro = 1.5;
x = [ri*cosd(theta) ro*cosd(-theta) 0];
y = [ri*sind(theta) ro*sind(-theta) ri*sind(theta(1))];
plot(x,y), axis equal

[Hakan Güngör]

It works for my hw thanks. But I mean I want my plot with not only 2 r value (ri,ro). I want to see my plot with r:0.5:0.1:1.5; (means 10 value or more). What should I do? Do I need a for loop?

[Alan Stevens]

Yes, use a for loop. You haven't said if the values from 0.5 to 1.5 refer to ri or ro. Presumably you need to specify values for both.

[Hakan Güngör]

thanks mate