Change row vector to column vector

Question

How can I change this into a column, at the moment all 750 entries are on one row?

p = normal(1:750)-1;

I have tried:

columns = 1;
p = normal(1:750)-1;
p = p(1:columns);

I have also tried:

rows = 1000;
p = normal(1:750)-1;
p = p(1:rows)';

Solution 1

I would imagine you could just transpose:

p = (normal(1:750)-1)'

Solution 2

It is common practice in MATLAB to use the colon operator : for converting anything into a column vector. Without knowing or caring if normal is a row vector or a column vector, you can force p to be a column vector, like so:

p = p(:);

After this, p is guaranteed to be a column vector.

Solution 3

Setting

p = p(:);

is indeed the best approach, because it will reliably create column vector.

Beware of the use of the ' operator to do transpose. I have seen it fail dramatically many times. The matlab operator for non-conjugate transpose is actually .' so you would do:

p = p.'

if you want to do transpose without taking the complex conjugate.

Comments

[G Gr]

Thanks Dan could not find that anywhere in the documentation! previous question is why I asked.

[Dan]

sure btw this is probably what you were trying in your first attempt: p = p(1:length(p), 1); but using ' to transpose is definitely the correct approach.

[John]

So, a = 1:5 generates a row vector, but b=a(:) is a column vector?

[user327301]

This is my preferred method, since it will not convert a column vector to a row vector if you already in fact had a column vector.

[Eitan T]

@TanWang Because this is how the programmers of MATLAB wanted it to work.

[jvriesem]

If anyone is using complex numbers, note that the ' (or ctranspose()) operator is the complex conjugate transpose. More info in the documentation here: mathworks.com/help/matlab/ref/ctranspose.html. If you want the nonconjugate transpose, use .' (or transpose()) instead.

[Daddy Kropotkin]

Very nice! This is exactly the thing I needed, and I could mirror @raoulcousins