add column of data to array in Matlab

Hi my algorithm I have created produces outputs as such:

1 x 45 column vector

How can I then add another 1 x 45 column vector of data to this previous one to make a 2x45, 3x45 etc?

Answer 1

[Cam Salzberger]

Hello Kieran,

In MATLAB, we use row x column notation. So a column vector with 45 elements would be 45 x 1.

Use [], horzcat, or just cat to do the concatenation.

a = rand(45, 1);
b = rand(45, 1);
c = [a b];
c = horzcat(a, b);
c = cat(2, a, b);

Note that if you're building an array through concatenation in a loop, then you're probably doing something inefficiently. You can preallocate the matrix, and then compute one row at a time instead.

-Cam