x0=2;
y0=3;
r=10; % radius
angl=3*pi/4;
angl=rem(angl,2*pi);
if angl<=pi
x=r*cos(angl):0.01:r+x0;
y1=sqrt((r^2-(x-x0).^2))+y0;
plot(x,y1)
else
x=-r:0.01:r+x0;
y1=sqrt((r^2-(x-x0).^2))+y0;
plot(x,y1);
hold on
x2=-r:0.01:-r*cos(angl-pi)+x0;
y2=-sqrt((r^2-(x2-x0).^2))+y0;
plot(x2,y2);
end
xlim([x0-r x0+r])
ylim([y0-r,y0+r])
axis square
