How to extract a row from a transpose of a matrix

Hi,

Say I do have a matrix M=[1 2; 3 4; 5 6]

And say that I want to extract the first row from the transpose of the M matrix

Without saving the transpose of M as another matrix like doing like M_trans = M' and k = M_trans(1,:)

How to do it in a one line??

M'(1,:) won't work

Answer 1

[Cedric]

Take the first column of the original matrix.

[Chamira Wickramasinghe]

yeah I did that. But still wanted to know if there's another way. Thank you so much for the tip. :) :)

[Cedric]

My pleasure! Don't forget to accept the answer if it helped.

In MATLAB there is not easy way to index the output of a function, here TRANSPOSE .', or complex conjugate transpose as you write it '.

[Jan]

@Chamira: Cedric is right: You cannot get the transpose on the fly by telling Matlab magically, that you do not want to create the transposed explicitly, to extract a subvector. There are 2 ways only:

1. Create the transposed explicitly: MT = M'; k = MT(1,:)
2. Create your own algorithm, which extract directly, what you need: k = M(:,1).'.

The work must be accomplished anywhere: Either in Matlab by calculating the complete transposed matrix, although only a part is needed, or inside your brain, such that the indirection over the transposition is omitted. But there is no smart way to let Matlab perform the task of thinking.