# How to concatenate several matrices into one matrix?

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Negar on 17 Jan 2015
Answered: Negar on 18 Jan 2015
Hello all,
I have 3696 matrices with different number of rows but similar number of columns. Is there a way to concatenate them? I know how to do this with two matrices by C = [A B], but what about these many?
Thank you, Negar

Shoaibur Rahman on 17 Jan 2015
Perhaps, you mistyped. It is C = [A; B] for different number of rows, but similar number of columns. Anyway, how your matrices are named, like do they have a regular pattern? If I assume that they are named as A1, A2, A3..........A3696, then you can use the following technique:
A1 = rand(3,5); % matrix 1
A2 = rand(2,5); % matrix 2
.
.
. % all other matrices in between
.
.
A3696 = rand(1,5); % matrix 3696
B = [];
for k = 1:3696
m = strcat('A',num2str(k));
B = [B; eval(genvarname(m),'=m')];
end
Shoaibur Rahman on 17 Jan 2015
If you have to read matrices from a file, as Image Analyst says below that sounds more reasonable, then it will be easier, but vastly depend on how your data is organized. Very roughly speaking, replace m in this code by the header names (which are supposed to be names of the matrices).

Image Analyst on 17 Jan 2015
It seems doubtful that you'd have 3696 uniquely named variables in your program so I guess you must be planning on retrieving these matrices from files. In that case, use the code in the FAQ: http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

Negar on 18 Jan 2015
Hello, sorry for answering so late, my problem is unfortunately more complex than what I had imagined. I'll try to post it again. Thank you for taking the time. Negar