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Topic: vector/matrix manipulation question
Replies: 3   Last Post: Feb 14, 2013 6:37 PM

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 P Posts: 26 Registered: 8/4/08
vector/matrix manipulation question
Posted: Feb 14, 2013 3:07 PM

Hello,

I'm trying to figure out the simplest Matlab syntax to deal the following 2 scenarios:

1. let a = [1 2 3; 4 5 6]

what's the cleanest syntax to duplicate each row of a by a factor of x? Let say x = 2, I want to final outcome looking like

b = [1 2 3; 1 2 3; 4 5 6; 4 5 6]

if I use repmat(a, 1, 2), I get
b = [1 2 3; 4 5 6; 1 2 3; 4 5 6]

This is not really what I wanted

2. Is it possible to transpose an inner dimension of a multi-dimension matrx? Let say

[2 3 4] = size(a)

I want to transpose the latter 2 dimension of a such that

[2 4 3] = size(b)

Is there a simple command that can do these?

For both problems, I ended up writing for loop to perform the desired matrix transform. I'm curious if I miss a simpler solution somewhere

Thanks!

Date Subject Author
2/14/13 P
2/14/13 Bruno Luong
2/14/13 P
2/14/13 Bruno Luong