If A is a matrix, A(:) produces the columns in a vector. Is there a parallel function for rows?

A=[1,2,3;4,5,6;7,8,9]. Then A(:) returns [1;2;3;4;5;6;7;8;9]. Is there an operator that will produce [1,2,3,4,5,6,7,8,9]?

Answer 1

[James Tursa]

First, I assume your example result is a typo, since A(:) will return the elements in column order, not row order. E.g.,

>> A=[1,2,3;4,5,6;7,8,9]
A =
     1     2     3
     4     5     6
     7     8     9
>> A(:)
ans =
     1
     4
     7
     2
     5
     8
     3
     6
     9

To get them out in row order, transpose A first. E.g.

>> A=[1,2,3;4,5,6;7,8,9]
A =
     1     2     3
     4     5     6
     7     8     9
>> reshape(A',[],1)
ans =
     1
     2
     3
     4
     5
     6
     7
     8
     9

[Rajmohan]

Both return [1,4,7,2,5,8,3,6,9] instead of [1,2,3,4,5,6,7,8,9]

[James Tursa]

Ummm ... that was a direct copy from my MATLAB command window, and the order is clearly 1,2,3,4,5,6,7,8,9 as shown. If you want the result as a row instead of a column, then simply:

reshape(A',1,[])