Delete parts of plotted figures?

I have made this image

with this code:

axis equal
hold on

caca=2*pi();
ang=linspace(0,caca);
xp=5*cos(ang);
yp=5*sin(ang);

circ=[xp;yp];
plot(xp,yp,'r');


L1=[-8 8; 3 3];                      
plot(L1(1,:),L1(2,:),'b')

And I want to delete the part of the line within the circle and the part of the circle under the line so the image results like this:

Is there any way of achieving that? How can I do it?

Answer 1

[Star Strider]

Try this:

axis equal
hold on
caca=2*pi();
ang=linspace(0,caca);
xp=5*cos(ang);
yp=5*sin(ang);
circ=[xp;yp];

L1x = linspace(-8, 8);
L1y = 3*ones(size(L1x));
L1=[L1x; L1y];                                      % Re-define Line
incirc = inpolygon(L1x,L1y,circ(1,:),circ(2,:));
L1(1,incirc) = NaN;
L1(2,incirc) = NaN;

plot(xp(yp>=3),yp(yp>=3),'r');
plot(L1(1,:),L1(2,:),'b')

.

[ErikJon Pérez Mardaras]

I have tried that and appears some gaps in the figure

[Star Strider]

Increase the resolution of ‘ang’ and ‘L1x’ and the gaps essentially disappear:

ang=linspace(0,caca, 5000);
    . . .
L1x = linspace(-8, 8, 5000);

producing:

There will always be small gaps because there are not an infinite number of points in ‘ang’ and ‘L1x’.

[ErikJon Pérez Mardaras]

thanks!

[Star Strider]

As always, my pleasure!

Answer 2

[Fangjun Jiang]

use patch() or fill()? This one does part of it.

patch(xp,yp,'white')

[ErikJon Pérez Mardaras]

I have tried that and appears and strange figure with black borders