MATLAB: Problem with storing for-loop values in array

factorial

Hi!
I know the question of storing for-loop values in an array has been asked before.
I am trying to compare the time it takes to perform factorial calculations with two different methods. I will just post one of the methods since it is the only one I am having trouble with.
My code is this:
 clear all, close all, clc
 n=150;                      %factorial to calculate
 T2=zeros(1,n);              %empty (1 x n)-vector

 B=zeros(1,n);               %empty (1 x n)-vector
 p=n;
    tic;
for i=1:n
    while n>1
    n=n-1;                   %calculates n!                 
    p=p*n;                   %calculates n!   
    B(1,n)=p                 %store values of factorial in (1 x n)-vector
    end;
    T2(i)=toc;               %times the function
end;
plot(T2,B)                   %plots the function
The problem I am having is that, instead of storing each value of p in one of the columns of the vector B and thus being able to track the growth of the factorial, all of the columns of the vector B, except for the last one which is just showing the final value. All of the values of p seem to be accurate.
How can I write this to instead store each value of the factorial in its own column in the vector B?
I hope I made it possible to understand my question!
Thanks in advance.

Best Answer

After the first iteration of the for-loop n has become 1. So for the next iteration, the while-loop is never entered. so T(k) will be almost the same as T(k-1), and B(k) will be zero, for k > 1.
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