How do I graph the Laplace transform of a function?

So I've been working on this problem for a little while and I cannot seem to get past this one issue. The goal of the problem is to find the Laplace transform of a function and graph that Laplace transform on the same plot as the original function. I have a book for this class and I followed all of the instructions to a tee and I'm still getting an error when I try and run the code. If anyone could help me figure out my issue, that would be appreciated.

From Part A:

syms s t Y

% Defining the function h(t) with all of the necessary steps.
h = 1 + heaviside(t - pi)*(-1 - 1) + heaviside(t - 2*pi)*( 1 - (-1)) + ...
    heaviside(t - 3*pi)*(-1 - 1) + heaviside(t - 4*pi)*(1 - (-1)) + ...
    heaviside(t - 5*pi)*(-1 - 1) + heaviside(t - 6*pi)*(1 - (-1)) + ...
    heaviside(t - 7*pi)*(-1 - 1) + heaviside(t - 8*pi)*(1 - (-1)) + ...
    heaviside(t - 9*pi)*(-1 - 1) + heaviside(t - 10*pi)*(1 - (-1));

% Plotting the function h(t).
figure(1)
ezplot(h, [0 30])
title('Part A: h(t) on the interval [0, 30]')
xlim([0 30])
ylim([-2 2])
hold off

Part B:

syms s t Y

eqn = sym(['D(D(y))(t) + y(t) = ' h]);
lteqn = laplace(eqn, t, s);
neweqn = subs(lteqn, {'laplace(y(t), t, s)', 'y(0)', 'D(y)(0)'}, {Y, 0, 1});
ytrans = simplify(solve(neweqn, Y));
y = ilaplace(ytrans, s, t);

figure(2); hold on
%ezplot(y, [0 30])
ezplot(h, [0 30])
title('Part B: Laplace of h(t) on the interval [0, 30] w/ the graph of h(t)')
xlim([0 30])
ylim([-2 2])
hold off

The error that I am getting is "Error in sym/horzcat (line 14) args = privResolveArgs(varargin{:});". It goes away whenever I comment out all of the Laplace transform things, so the error is inside of those statements. The initial value problem that I am trying to solve is D^2(y) + y = h(t), y(0) = 0, y'(0) = 1. h(t) is supposed to be a square wave that goes from 1 to -1 for every value of pi and stays at that value until the next value of n*pi for 0 <= n <= 10.