MATLAB: Fourier Series Expansion Graph Help

domainfourier series expansiongraphsMATLAB

So I am building the code to perform a Fourier Series Expansion, specifically for the function e^(-x) for the domain of 0=<x<2.
My graph looks like this, I don't know how well you will be able to see it, but in essence my function e^(-x) starts at the beginning of the domain and not at 0.
If anybody knows how I can get the function to start at zero, any help would be appreciated.
syms x n s
f = exp(-x);
L = input('Please enter a value for the domain ');
max = input('Please enter a value for n ');
X= 0:.01:L;
Ao = (1/L) * int(f,x,-L,L);
An = (2/L) * int((f*cos(2*pi*n*x/L)),x,-L, L);
Bn = (2/L) * int((f*sin(2*pi*n*x/L)),x,-L, L);
A = An * cos(2*pi*n*x/L);
B = Bn * sin(2*pi*n*x/L);
s = Ao;
for N = 1:max
s = s + subs(A,n,N) + subs(B,n,N);
end
figure
fplot(s,[-L L])
hold on
fplot(f,[-L L])

Best Answer

If you want to plot them beginning at 0, remember to tell fplot:
figure
fplot(s,[0 L])
hold on
fplot(f,[0 L])
That will start them both at 0.