Integration over elapsed time

I have elapsed time and want to find velocity:(ie time would then be :[0 1 2 3 4 5 6]), any way to do this please, as following code only works when time is specified in increments:

etime = [0 1 1 1 1 1 1]; % elapsed time in sec

a = [0,2,4,7,11,17,24]; %acceleration in m/s^2

v(1)=0;

for k=1:6

    v(k+1) = trapz(etime(k:k+1), a(k:k+1))+ v(k);

end

disp([v'])

Answer 1

[Walter Roberson]

t = cumsum(etime);
v = cumtrapz(t, a);

[Aswas]

Thanks Walter.