How do I flip a function across its center line?

Question

Say a defined function begins with point (a,b) and ends with point (c,d). How do I flip this function about its vertical center line (described by x = (c-a)/2)?

Thanks in advance!

c = 5.2;
alpha = 0; 

R = [cosd(alpha) sind(alpha) 0; -sind(alpha) cosd(alpha) 0; 0 0 1]; 
l1_vector = [-sqrt(3)*c; 0; 0];
l1_prime = R*l1_vector;

iter = 1;

for i=1:1201
        R = [cosd(alpha) sind(alpha) 0; -sind(alpha) cosd(alpha) 0; 0 0 1]; 
        l1_prime = R*l1_vector; 
        a = l1_prime(1)
        b = l1_prime(2);
        alpha = alpha+.1;
        data1(iter,1:2)=[a,b];
        iter=iter+1;
    end      

a = data1(:,1);
b = data1(:,2);

plot(wrev(a)+a(end)-a(1),b)
axis equal

Answer 1

Depends how your function is defined really, but if you have a vector of x values and another with corresponding function values y, then

plot(x,y)

plots the function normally, and

plot(a,b,2*a(end)-a(1)-cumsum([0;diff(a)]),b)

plots the flipped and translated function.