Question: Plotting a point plot.......

My problem looks as follows................pts1FIXED comes from dsolved solution......it plots a empty figure...and i checked that l(the data pairs looks fine)..
--------------------------------------
Energy:=array(1..450);

Time:=array(1..450);
for i from 1 to 450 do

Energy[i]:=-1*((32*G*Inertia^2*e^2)/(5*c^2))*pts1FIXED(i);
end do:
l := [[t,Energy[t]] $t=1..450]:
plot(l,style=point,symbol=circle,color=blue);
----------------------------------------------------
what am i doing wrong
Please Wait...