Fill area between circles

Lets say I have 2 circles. They are concentric about the origin. What is the best way to fill the area between the 2? I am using this circle function that I found on Mathworks. The larger circle has a diameter of 10 and the smaller circle has a diameter of 5.

function circle(d,x,y,ang_start,ang_end,step)
ang=ang_start:step:ang_end; 
xp=(d/2)*cos(ang);
yp=(d/2)*sin(ang);
plot(x+xp,y+yp);
end

Thanks,

Answer 1

[the cyclist]

Here is one way:

% Get data for the two circles
[xp5, yp5] = circle(5,0,0,0,2*pi,0.01);
[xp10,yp10] = circle(10,0,0,0,2*pi,0.01);

% Draw the two circles
figure
hold on
plot(xp5,yp5)
plot(xp10,yp10)

% Fill in the area by defining the polygon that is defined by tracing the inner circle and then back along the outer circle
fill([xp5 flip(xp10)],[yp5 flip(yp10)],'g')

% Cover up the connecting line in the same color
h = line([xp5(1) xp10(end)],[yp5(1) yp10(end)]);
set(h,'Color','g')

% Set the axes to have equal length, so that they *look* like circles
axis equal

[Benjamin Salak]

Thanks!