how to plot this ?

i have a circle and i want to plot his half radius in the same figure can anyone help me :

angle=linspace(0,2*pi,360);
x=cos(angle);
y=sin(angle);
plot(x,y)
axis('equal')

[Walter Roberson]

I am not sure what you mean about "his half radius" ? Do you mean a second circle with half the radius? If so then plot(x/2, y/2)

[diadalina]

thank mr walter for your response, i mean by his half radius, the line that cuts its half radius

[Walter Roberson]

Which angle should it be drawn at?

Answer 1

[KSSV]

angle=linspace(0,2*pi,360)';
C = [0 0] ; 
R = 1 ; 
x=C(1)+R*cos(angle);
y=C(2)+R*sin(angle);

% 
x1 = R/2*cos(angle) ; 
y1 = R/2*sin(angle) ; 

plot(x,y)
hold on
C1 = repmat(C,length(angle),1) ; 
plot([C1(:,1) x1]',[C1(:,2) y1]')
axis('equal')

[diadalina]

thank you mr KSSV for your answer but i want somthing like this :

[Walter Roberson]

hold on
plot([0 1], [0 0])
hold off

This relies on the fact that the center of the circle is at 0, 0 and the radius of the circle is 1.

[diadalina]

thank you mr walter for your help ;

[KSSV]

angle=linspace(0,2*pi,360)';
C = [0 0] ; 
R = 1 ; 
x=C(1)+R*cos(angle);
y=C(2)+R*sin(angle);
% 
x1 = R*cos(0) ;
y1 = R*sin(0) ; 
plot(x,y)
hold on
plot([C(:,1) x1]',[C(:,2) y1]')
axis('equal')