How to select the first i columns of a matrix?

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SSG_newbiecoder
SSG_newbiecoder 2018-3-20
评论： SSG_newbiecoder 2018-3-20
Hello, I have a nxn matrix X. I need to select the first i columns alone of the matrix within a for loop. How can I do this? I'm not able to figure out the indexing for this. This is what I want
X =
-1.5145 -1.5475 -1.5556
-1.4254 -1.4856 -1.5085
-1.3363 -1.4237 -1.4614
first iteration
-1.5145
-1.4254
-1.3363
second iteration
-1.5145 -1.5475
-1.4254 -1.4856
-1.3363 -1.4237
  2 个评论
M
M 2018-3-20
编辑：M 2018-3-20
Maybe you should start by reading how to write for loop and read about indexing matrices in matlab.
Stephen23
Stephen23 2018-3-20
A good place to learn basic (and important!) MATLAB concepts is by doing the introductory tutorials, which are highly recommended for all beginners:
https://www.mathworks.com/help/matlab/getting-started-with-matlab.html
These will teach you many important concepts that you need to know.

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采纳的回答

Birdman
Birdman 2018-3-20
for i=1:size(X,2)
X(:,1:i)
end

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