How to define this function?

How can I define the second periodic function(x2(t))?

here is the definition of the first function that I defined.

close all;clear;clc;

Fs = 50;
T = 1/Fs;
t = -2*pi:T:2*pi;
L = length(t);

%peroid 2*pi first function
X1 = 1/2*(1+square(2/3*(t+pi),200/3));
Y1 = fft(X1);

f = Fs*(0:(L-1))/L;

subplot(1,2,1);
plot(t,X1);

subplot(1,2,2);
plot(f,abs(Y1));

[John D'Errico]

x2 is NOT a function of t. Period. As an integral, t goes away.