# how to combine matrix easier

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metumetu on 11 Mar 2020
Commented: BobH on 12 Mar 2020
Hello,
I want. How can i do this (below code block) with a loop?
I have to do this with a loop because, i will be doing this with a lots of a matrices. please help me.
Thank you.
a1=[1,2,3; 4,5,6; 7,8,9]
a2=[10,11,12; 13,14,15; 16,17,18]
a3=[19,20,21; 22,23,24; 25,26,27]
b1=[a1(:,1);a1(:,2);a1(:,3)]
b2=[a2(:,1);a2(:,2);a2(:,3)]
b3=[a3(:,1);a3(:,2);a3(:,3)]
C=[b1,b2,b3]
##### 2 CommentsShowHide 1 older comment
Ameer Hamza on 11 Mar 2020
BobH, the actual problem is that OP wants to do it with lots of matrices, so manually concatenating array will not be practical.

Ameer Hamza on 11 Mar 2020
If the data is stored properly, i.e., in cell array instead of using separate variables, the following one-liner will work
a{1}=[1,2,3; 4,5,6; 7,8,9];
a{2}=[10,11,12; 13,14,15; 16,17,18];
a{3}=[19,20,21; 22,23,24; 25,26,27];
C = cell2mat(cellfun(@(x) x(:)', a, 'UniformOutput', 0)')';
BobH on 12 Mar 2020