# how to plot this ?

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Commented: KSSV on 23 Apr 2019
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 on 21 Apr 2019
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)
thank mr walter for your response, i mean by his half radius, the line that cuts its half radius
Walter Roberson on 21 Apr 2019
Which angle should it be drawn at?

KSSV on 22 Apr 2019
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')

Show 1 older comment
Walter Roberson on 22 Apr 2019
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.
thank you mr walter for your help ;
KSSV on 23 Apr 2019
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')