# Math Help - Is this a way to represent column vectors.......

1. ## Is this a way to represent column vectors.......

Hi,
I came across a representation of matrix i donot clearly understand. Is D[. , t] reprentation of a row of column vector? If not, then can anybody tell me what the dot (.) represents.

Thanks

2. ## Re: Is this a way to represent column vectors.......

Hey ak786.

This operation takes two matrices and augments them column-wise. To use an example from Octave:

>> >> A = [0,1,2;3,4,5;6,7,8]
A =

0 1 2
3 4 5
6 7 8

>> X = [1;2;3]
X =

1
2
3

>> B = [A, X]
B =

0 1 2 1
3 4 5 2
6 7 8 3

Note the requirement with the number of rows for each matrix.

3. ## Re: Is this a way to represent column vectors.......

thanks for the reply, but do u mean that '.' represents augmenting two matrices column-wise??

4. ## Re: Is this a way to represent column vectors.......

I think the dot just refers to a matrix of some sort.