Can anyone help me understand following code consisting of multiple inputs in Simulink to get a response with impulse & without impulse , & comparing it with analytical

%%

clear all

close all

clc

m=1200;k=400000;zta=0.4;

c=2*zta*sqrt(m*k);wn=sqrt(k/m);

wd=sqrt(1-zta^2)*wn;

td=0.072;

As = [0 1;-k/m -c/m];

Bs = [0 1]';

Cs1 = [k/m c/m];

Cs2 = [1 0];

Ds = 0;

Asj = [0 1;-k/m -c/m];

Bsj = [0 0;k/m c/m];

Csj = [1 0];

Dsj = [-1 0];

fs=10000;%sampling frequency

sim('speedbump1.mdl');

plot(time,output(:,[1 2]));

%% Analytic data

% plugg in

syms tau t

dt=0.001;

%w1 0<t<td

time1=0:0.001:0.072;

w11=1/(wd)*int(190.36*sin(pi/td*tau)*(exp(-zta*wn*(t-tau)).*sin(wd*(ttau))),tau,0,t);

w11=double(subs(w11,t,time1));%without impulse

t=time1;h1=0.26*(exp(-zta*wn*t).*sin(wd*t));%first impulse

w12=w11-h1;%without impulse

%w2

syms t

time2=0.072:0.01:10;

w21=1/(wd)*int(190.36*sin(pi/td*tau)*(exp(-zta*wn*(t-tau)).*sin(wd*(ttau))),tau,0,td);

w21=double(subs(w21,t,time2));%without impulse

t=time2;

h1=0.26*(exp(-zta*wn*t).*sin(wd*t));%first impulse

h2=0.26*(exp(-zta*wn*(t-0.072)).*sin(wd*(t-0.072)));

w22=w21-h1-h2;%with impuse%%

save analyticdata

%%

load analyticdata;%load analytic data

figure

plot(time,output(:,2),'linewidth',2);hold on

plot(time1,real(w12),'r.','linewidth',2);

plot(time2,real(w22),'r.','linewidth',2);

title('Response with Delta Function')

xlabel('Time (sec)','fontname','times','fontsize',14);

ylabel('Displacement (m)','fontname','times','fontsize',14)

title('Numerical response overlayed with analytic solution with impulse impulses','fontname','times','fontsize',14)

legend('Simulink','Analytic');

xlim([0 1]);

figure

plot(time,output(:,1),'linewidth',2);hold on

plot(time1,real(w11),'r-.','linewidth',2);

plot(time2,real(w21),'r-.','linewidth',2);

xlabel('Time (sec)','fontname','times','fontsize',14);

ylabel('Displacement (m)','fontname','times','fontsize',14)

title('Numerical response overlayed with analytic solution without impulses','fontname','times','fontsize',14)

legend('Simulink','Analytic');

xlim([0 1]);

%%

figure

plot(time,in(:,1),'-.','linewidth',2)

hold on

plot(time,in(:,2),'r')

xlabel('Time (sec)','fontname','times','fontsize',14);

ylabel('Acceleration (m/s^2)','fontname','times','fontsize',14)

xlim([0 0.08])

legend('Without Impulse','With Impulse');