Please any idea of how I can flip an arc?

I have an arc of a circle which is facing the centre of the circle but I want to flip this arc by 180 degrees to make it face the opposite direction as illustrated in the attachment.

Answer 1

[Star Strider]

Try this:

a = linspace(0, pi/2);
r = 1;
x = r*cos(a);
y = r*sin(a);

figure
subplot(2,1,1)
plot(x, y)
axis equal
title('Before')

subplot(2,1,2)
plot(r-x, r-y)
axis equal
title('After')

Subtract the x and y vectors from the radius to flip the circle.

[Steve Arum]

Thanks a lot @Star Strider for your swift answer.

[Star Strider]

As always, my pleasure.