How to add another scenario to my code?

I am struggling to include a scenario to my code.

This is the original code

clear; clc;
y0=[5, 120, 120]; %input problems specification
t=linspace(0,100,101);   %Generate the value of t sing linspace
%Call ode45 and store solution in soln
[t, y]=ode45(@f,t,y0,odeset('RelTol', 1.E-6, 'AbsTol', 1.E-6, 'PelTol));

% y1=deval(t,soln));     %Retieve value of y(1) from soln Scenario 2
% y2=deval(t,soln));     %Scenario 1

plot(t,y(:,2),'r',t,y(:,3),'b','Linewidth',2);
xlabel ('t (min)'); ylabel('Outlet Temp (deg C)');
legend('Scenario 2', 'Scenario 1');
grid on;                %Add grid to plot
title('ode45 S2'); %Add title to plot 
%
%User specified function for dydt for each dependent variable
%
function dydt=f(t,y)
V=30; p=62.4; Tin=60; F=5; Q=1000; tauTs=1.25; tauTv=.17;
dydt(1)=(5-y(1))/tauTv;
dydt(2)=((p*F*(1))*(Tin-y(2))+Q)/(p*V*(1));
dydt(3)=(y(2)-y(3))/tauTs;
dydt=dydt'

it gives me two lines in one graph. I'd like to add another scenario to it. This is the code I wish to incorporate somehow

s3=[]; theta=1; 
for j=1:length(s2)
    if (t-theta)<=0
        s3(j)=s2(0)
    else
        s3(j)=s2(t-theta)
    end
end

[Walter Roberson]

for j=1:length(s2)

Is s2 a variable, or is it a non-anonymous function that can be invoked with no parameters, after which you would be taking length() of the result returned by function s2 ?

    s3(j)=s2(0)

if s2 is a variable then you cannot index it at 0.

Have you considered

s3 = zeros(size(t));
s3(1:theta) = s2(1);
s3(theta+1:end) = s2(1:end-theta);

[Rebecca Reyes]

https://www.mathworks.com/matlabcentral/answers/1563996-how-to-add-another-scenario-to-my-code#comment_1784866

I believe s2 is a non-anonymous function.

Actually here is what i was trying to recreate in MatLab. See attached image. Really appreciate the help!

[Rebecca Reyes]

https://www.mathworks.com/matlabcentral/answers/1563996-how-to-add-another-scenario-to-my-code#comment_1785176

adding more to the comment: theta is equal to 1

[Walter Roberson]

The code I showed should work for nonnegative integer theta. It would need some adjustments for negative delay or non-integer delay