HELP to correct the codes of the graph of the solution of the differential equation with piecewise constant argument at Matlab

clc; clear; clear all;
a=1.5;  
d0=1; 
v0=1;
nu=sqrt(2.5);
sumxx=[];
k=250;
for p=1:k
    T=linspace(0.25.*(p-1),0.25.*p,100);
    sumx=d0.*cos(nu.*T)+(v0./nu).*sin(nu.*T)+((a.*d0)./nu.^2).*(1-cos(nu.*T));
for n=0:p-2
    K=OMEGAm(a,n,nu,v0,d0).*(1-cos(nu.*(T-(0.25.*(n+1)))));
    sumx=sumx+(a./nu.^2).*K;
end
% sumx=sumx.*x0;
sumxx=[sumxx,sumx];
clear sumx
end
tt=linspace(0,k,k*100);
plot(tt,sumxx)
xlabel('t')
ylabel('x(t)')
grid on
hold on
----------------------------------------------------------------
function w=OMEGAm(a,n,nu,v0,d0)
M=[(1-a./(nu.^2)).*cos(nu.*0.25)+a./(nu.^2) sin(nu.*0.25)./nu;-nu.*(1-a./(nu.^2)).*sin(nu.*0.25) cos(nu.*0.25)];
w=[(1-a./(nu.^2)).*cos(nu.*0.25)+a./(nu.^2)-1 sin(nu.*0.25)./nu]*(M.^n)*[d0;v0];
end