Could anyone help me to solve the issue for the following code

Code:
Bmax=2000; 
noise=1e-5; 
p_fix=0.05; 
for it=1:2
G =[4.2638    4.2227    4.2658    4.4176    4.6851    5.0623
    2.2943    2.3644    2.4166    2.4525    2.4750    2.4880
    0.0637    0.0599    0.0563    0.0533    0.0509    0.0494
    0.0427    0.0429    0.0431    0.0432    0.0434    0.0435];
C =[4.2638         0         0         0         0    5.0623
     0         0         0         0    2.4750         0
     0         0    0.0563         0         0         0
     0    0.0429         0    0.0432         0         0]
     t=4;
     r=6;
     throughput =((Bmax.*log(1+((p_fix).*C))./ noise))
     overall_throughput = sum(sum(throughput))
     output(t,r)=overall_throughput
     output_it(t,r,it)=output(t,r)
    end
If i run the following code it executes.
But for every iterations the output remains the same value.
Could anyone help me how to get different values of output for every iteration.

[Greg]

Everything in there is a constant. You can move it all out of the loop. The first thing to look for to spot this is not using your loop variable anywhere but an assignment index.

At least one value somewhere needs to change inside the loop, either randomly or based on the loop iteration.

[Greg]

Also, why all the intermediate variables?

overall_throughput = sum(sum(throughput)) 
output(t,r)=overall_throughput
output_it(t,r,it)=output(t,r)

Can be

output_it(t,r,it)=sum(sum(throughput))