Help with differential equations in Matlab

Hello, I have two small issues with some matlab code to solve an ODE. If you are experienced it should not take you more than a few minutes 1) I want to solve the ODE below (eqn) syms L R C t Q(t) U = V(t); dQ = diff(Q,t); d2Q = diff(dQ,t); DEQ = L*C*d2Q + L/R*dQ + Q; DEQ = subs(DEQ, {L, R, C}, {1, 1, 1}); eqn = (U == DEQ); I get the appropriate answer by using dsolve if V(t) is a well defined function ie: sin(t), now I want to solve the same ODE for V(t) equal an array of number that I get from a previous calculation. for testing you can take these time and voltage arrays t = 0:1/12:19.99; Vc = [1:3/(7*12-1):4,4:-1/(3*12-1):3,3:3/(7*12-1):6,6:-1/(3*12-1):5]; 2) I can solve the same ODE by using the transfer function, however it looks like the lsim function is not taking my initial condition 0.3 and always starts from zero R = 1; L = 1; C = 1; G = tf([1/(L*C)],[1 1/(R*C) 1/(L*C)]); t = 0:1/12:19.99; Vc = [1:3/(7*12-1):4,4:-1/(3*12-1):3,3:3/(7*12-1):6,6:-1/(3*12-1):5]; x0 = 0.3; %initial condition figure hold on plot(t,Vc) plot(t,lsim( G, Vc, t, 0.3 ))