how to save the index during for loop?

How to save the index data and as i am not getting it? i have mention in the loop my question.

thank you

l=30000;
m=1;
n=180;
k=1;
c20=-0.00108263;
GM=398600.44;                             %unit is in km^3/s^2

%%unknown data
i=1.11784815920563;
e=0.00381415453739464;
a_e=26560.4021;                          %semi-major of the earth value is in km
a=26500;                                 % semi major axis of the GPS
n = sqrt(GM/(a*a*a));


%% help me in the loop for plotting ????????????????????????
for a=6838:1:l
 i=deg2rad(55);
 e=0.01;
d_omega_drei(k,:)=(3*n*c20*a_e^(2))/(4*(((1-(e*e))^(2))*a^(2)))*(1-5*cos(i)^(2));
d_Omega_drei(k,:)=(3*n*c20*a_e*a_e)/(2*((1-(e*e))*(1-(e*e)))*a*a)*cos(i);
  


 k=k+1;
end
%case-1
figure();
grid on
xlabel('Omega dot and omega dot')
ylabel('a')

plot(d_omega_drei,a);
hold on
plot(d_Omega_drei,a);
hold off 

Answer 1

[David K.]

A couple different things can fix this, but I would suggest this one just creating the variable a again after your for loop ->

for a = 6838:1:l
    ...
end
a = 6838:1:l;

Also, after doing this if the plot looks weird to you still, I would suggest switching a and d_omega_drei in your plotting.