Re: n vectors of m rows from a m*n matrix

[James Sherman Jr.]

On Sun, Feb 10, 2013 at 12:18 PM, robyandfra <address@hidden> wrote:
> Hi
> i have a matrix of m*n dimension (m and n are variable and depend on the
> previous part of the program).
> I need to work on each column of the matrix.
> how can a said to octave that it had to create:
> vector1
> vector2
> vector3
> .
> .
> .
> vectorn
> and keep them in the memory? Remember than n is variable...
> I have to add members on each vector so i need them saparated..
>
> i try in this way: example
>
> t=1:1:8 - time:length(t)=n
>
> A=[1,2,3,4,5,6,7,8;2,3,4,5,6,7,8,9]
>
> for e=1:length(t)
>         b=A(:,e)
> end
>
> but i get only one vector that is the last column of the matrix A.
>
>
> SOS
> bye
>
>
>
>
> --
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Just to clarify, you want to have a variable number of vectors, and
that each vector has a different number of elements in it?

If so, what I think you want to use is a cell array.  Cell arrays work
similar to matrices but they allow different variable types in each
element.  For example:

A = cell(3,1) % create a 3 by 1 cell array
A(1,1) = [1 2 3]; % assign the vector [1 2 3] to element 1,1
A(2,1) = [4 5];
A(3,1) = 'foo';

And if you wanted to access the first element (this is where things
get kinda weird), you have to use curly brackets instead of the usual
parenthesis:

> A{1,1}
ans =

   1   2   3

Hope this helps,

James Sherman