how can i get a horzenital vector?

 X = [2 1 5 1
      5 4 8 1
      1 4 5 7];
if i use X1 = X(:);
 the output is X1=[2
                   5
                   1
                   1
                   4
                   4
                   5 
                   8 
                   5
                   1
                   1
                   7]
but i wante the out put is X1 =[2 1 5 1 5 4 8 1 1 4 5 7];

thank you very much

Answer 1

[Andrei Bobrov]

X1 = reshape(X',1,[])

[Andrei Bobrov]

My typo! Corrected...

Thanks Fangjun!

[Jan]

@Fangjun: Without the transpose, you get X1 = [2,5,1,...], but Amal wants [2,1,5,...] - the data in row order.

Answer 2

[Fangjun Jiang]

X1=X';
X1=X1(:);

Answer 3

[Daniel Shub]

If there is any chance that you matrix will have complex numbers you need to be careful with the difference between ' (ctranspose) and .' (transpose). To be clear I might go with:

X1 = transpose(X(:));

I do not know if there is a performance difference between ctranspose and transpose for real matrices.

[Sean de Wolski]

There is not. Though there was a bug with ctranspose in the original release of R2009b.