How can I save a vector in a for loop to a pre-allocated cell if my first value of the loop (i) is not 1?

I am trying to save a vector for each iteration into a pre-allocated cell location---> sol = cell(1,10) ;

My for loop does not start at 1. It is:

for i = 20:5:60

Each time I try allocating this vector to the cell in the loop by using: sol{i} = results , it only saves the vector from the last iteration and leaves all the other cells empty.

Does anyone know how I can fix this to save results from each iteration into this cell? Thank you so much

Answer 1

[Ameer Hamza]

Write the for-loop like this

x = 20:5:60;
for i = 1:numel(x)
    % instead of i write x(i)
    sol{i} = results;
end

[ERL]

Thank you for your quick response! I am still having problems because I need i to be 20:5:60 because I am using this to select specific frames of data.... is there another way to do this? Thanks for your help

[Ameer Hamza]

Yes, you can still use 20:5:60. As I mentioned in my answer, you can replace all the 'i' inside for-loop with 'x(i)'. Both are equivalents.

[ERL]

I tried this as well and it is still only saving the last iteration results in one cell...not sure what I am doing wrong at this point.

[Ameer Hamza]

Can you paste your code?

[ERL]

rang = 20:5:60 ;
Sol = cell(10); %changed this to save larger range of data

 for i = 1:numel(rang) 
    filename = strcat(files.folder,files(rang(i)).name);
.
. %I have a lot of other code in the middle that just analyses the image
.
res = regionprops(image,'Area','EquivDiameter');
AreaT = [res.Area] ; 
DIAMETERS = [res.EquivDiameter] ; %returns vector of values
Sol{i,1}= DIAMETERS ;

end

[Ameer Hamza]

Can you add a breakpoint (https://www.mathworks.com/help/matlab/matlab_prog/set-breakpoints.html) at the line

Sol{i,1}= DIAMETERS ;

and see if it runs one time or multiple time and what are the values of i at each iteration.

[ERL]

Not sure why, but it seems to be replacing the Sol{10,1} each time the loop is run

[Ameer Hamza]

Can you see if there is a line overwriting

i = 10

inside the for-loop.

[ERL]

it worked! I just restarted matlab and it worked for some reason. Thank you for all of your help!

[Ameer Hamza]

I am glad to be of help!