First column matrix into ones

Hello! How to extract the first coulmn of the matrix and make it ones?

For exmaple:

X = [1 4; 2 2; 3 6];
y = ones(X(:,1));

but it seems not work.

Thanks advanced for your help!

[Walter Roberson]

Okay, X(:,1) would be [1;2;3] .

Now what do you mean by "make it ones" ? Are you asking for a vector of ones with the same number of entries as there are rows in the table? Are you asking that afterwards X would be

1 4
1 2
1 6

??

[Y LIN]

Hello! Thanks for your reply. I'd like to extract only first column of the matrix, like example 3x2 into 3x1 and then make it all value as 1. How can I do that?

Answer 1

[Torsten]

X = [1 4; 2 2; 3 6];
X(:,1) = 1

or

y = ones(size(X,1),1)

depending on how your question is meant.

[Y LIN]

Hello! Thanks for your reply. I'd like to extract only first column of the matrix. Like example 3x2 extract 3x1 and then make all value as 1. How can I do that?

[Y LIN]

Oh, sorry for late refreshing the page! It works! Thank you so much for your help!