Wrong with matrix dimensions(lsim command)

It gives an error while using the lsim command.

a=[-15000 -10000 4000;-3333.333 -7000 -2666.666;2000 -4000 -8500];
b=[1000 0 0 ;333.333 0 0; 25000 0 0];
c=[1 0 0;0 1 0;0 0 1]; 
d=[0 0 0;0 0 0;0 0 0];
x0=[5.6,-4.82,6.51];  
t=0:0.01:5;
u=[5*t.^2+10;2*exp(t)+5;1];
  [y x]= lsim(a,b,c,d,u,t,x0);
   subplot(331),plot(t,x(:,1)); xlabel('t'),ylabel('I_1(t)'),grid
   subplot(332),plot(t,x(:,2)); xlabel('t'),ylabel('I_2(t)'),grid
   subplot(333),plot(t,x(:,3)); xlabel('t'),ylabel('I_3(t)'),grid
Error using vertcat
Dimensions of arrays being concatenated are not consistent.

Answer 1

[Paresh yeole]

In the input u, the dimensions are not properly assigned.

Try:

u=[5*t.^2+10;2*exp(t)+5;ones(size(t))];

[semih kahraman]

thank you