function [x, t]=spring(ks,rs,startx,d,m,c,tinc,atol,vtol)

currx=startx;
index=1;
v=vtol+1;
acc=atol+1;
while ( abs(v) > vtol || abs(acc)>atol )
fnet= -ks(0) * (currx- rs(0))+ ks(1)*(d-currx-rs(1)) - c * v;

acc=fnet/m;
v= v + acc* tinc;
currx=currx + v*tinc;
tott=tott+tinc;
x(index)= currx;
t(index)=tott;
end
plot (x,t);


end