"Index exceeds matrix dimensions" error in For Loop

I continue to get an "Index exceeds matrix dimensions" error when running the following for loop. It says there is an error in sym/subsref (line805), although my code only goes down ~200 lines, any help is much appreciated! Here is my code

 %Code
T=8;
t = -T/7:0.001:T/7;
syms t
y = 7*t.^2/(2*T);
N = 50;
k = -N:N; % vector of "k" coefficients.
ak = zeros(size(k));
omega = 2*pi/T; % frequency
dt = t(2) - t(1); % time delta
for n = 1:length(k)
    if k(n) == 0 
        ak(n) = a0;
    else
        ak(n) = (1/T)*sum(y.*exp(-1i*k(n)*omega*t)*dt); % Simulates the integral of the analysis equation
    end
end

end

Answer 1

[James Tursa]

You've got these two lines that define t differently:

t = -T/7:0.001:T/7;
syms t

What is your actual intent for t? The first line? Maybe comment out the 2nd line?

Answer 2

[Star Strider]

With two changes to your code, this runs:

syms t a0                                               % The ‘syms’ Statement Is First
T=8;
t = -T/7:0.001:T/7;
y = 7*t.^2/(2*T);
N = 50;
k = -N:N; % vector of "k" coefficients.
ak = sym(zeros(size(k)));                               % <— Create ‘sym’ Object
omega = 2*pi/T; % frequency
dt = t(2) - t(1); % time delta
for n = 1:length(k)
    if k(n) == 0 
        ak(n) = a0;
    else
        ak(n) = (1/T)*sum(y.*exp(-1i*k(n)*omega*t)*dt); % Simulates the integral of the analysis equation
    end
end