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matlab - Change for loop index variable inside the loop

I need to change my loop variable inside the iteration as I have to access array elements in the loop which is changing w.r.t size inside the loop.

Here is my code snippet:

que=[];
que=[2,3,4];
global len;
len=size(que,2)
x=4;
for i=1:len 
    if x<=10
    que(x)= 5;
    len=size(que,2)
    x=x+1;

    end
end
que

Array should print like:

2 3 4 5 5 5 5 5 5 5 

But it is printed like this:

2 3 4 5 5 5

In Visual C++ the array is calculated correctly and whole array of 10 elements is printed, which increases at run time.

How can I accomplish this in Matlab?

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by (71.8m points)

You should use a while loop instead of a for loop to do this:

que = [2 3 4];
x = 4;
while x <= 10
  que(x) = 5;
  x = x+1;
end

Or, you can avoid using loops altogether by vectorizing your code in one of the following ways:

que = [2 3 4];             %# Your initial vector
%# Option #1:
que = [que 5.*ones(1,7)];  %# Append seven fives to the end of que
%# Option #2:
que(4:10) = 5;             %# Expand que using indexing

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