How do you append to a matrix within a for loop?

Hi, I am using a for loop to process data (this part works fine). What I need to do is take the matrix (A) and after each loop update A to create one matrix. For instance, in the image below A is produced on the first loop, during loop 2 A "grows" to include the data from loop 1 and the data from loop 2, and so on.

Loop 1 produces a matrix, on the next iteration I need to append to this matrix the results of that loop, and so on until all of the data is processed.

It should be noted that the number of rows on each loop is unknown. However, the number of columns is fixed to 7.

Any ideas would be greatly appreciated please.

Answer 1

[José-Luis]

 your_result = [];

 for ii = whatever
     some_vector = some_function(of_something);
     your_result = [your_result; {some_vector}];
 end

[chels19]

Thanks, this has worked now.

[José-Luis]

My pleasure.

[Pradnya Raut]

Is there any faster way to do this, other than above method?

[ardeshir moeinian]

I find this a very easy and nice method... how can one do this for string arrays though?

[deejt]

Thank you very much @José-Luis!

I was wondering, is there also a possibility to define within the for loop at this section (marked with %here!) that I would like to insert the results in column number xy of my result matrix (here called "your_result")?

for ii = whatever
     some_vector = some_function(of_something);
     your_result = [your_result; {some_vector}];  % here! 
end

[Muhammad Ridwanur Rahim]

this is a beautiful solution. thank you @José-Luis

[Ruijie Zhu]

cheers mate

[Mani]

Nice one.

Answer 2

[Azzi Abdelmalek]

A=[1 2;3 4]
B=[4 5;6 7]
A=[A;B]

[chels19]

Thank you but this just replaces the data within the loop. I need to update A on every iteration so that it grows.

Answer 3

[SRIAKILAN S A]

% make an empty array
% the main command is end+1

N=[];
for i=0:10
    x=i*i;
    N(end+1)=[x]
end

N = 0

N = 1×2

0 1

N = 1×3

0 1 4

N = 1×4

0 1 4 9

N = 1×5

0 1 4 9 16

N = 1×6

0 1 4 9 16 25

N = 1×7

0 1 4 9 16 25 36

N = 1×8

0 1 4 9 16 25 36 49

N = 1×9

0 1 4 9 16 25 36 49 64

N = 1×10

0 1 4 9 16 25 36 49 64 81

N = 1×11

0 1 4 9 16 25 36 49 64 81 100

Answer 4

[Manuela]

I modified the code of the first answer in order to obtain a matrix and not a list of cells:

your_result = [];

for ii = whatever

some_vector = some_function(of_something);

your_result = cat(1,your_result,some_vector);

end