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To find values by using position vector

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Suppose matrix A=[1 3 5 7 9]. The position vector is known, which is, say, B=[ 3 4 ]. So the intended answer should be [ 5 7 ] which are elements at the 3rd and 4th places. Is there a function to achieve this? In fact the matrix A is high dimensional and there are many position vectors, and for loops seem not the most effective way...
Thanks in advance.

Accepted Answer

the cyclist
the cyclist on 18 Mar 2015
answer = A(B)
  1 Comment
Xia
Xia on 18 Mar 2015
Thank you so much. I must be too stupid to ignore the basic indexing. Thanks for your help!

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More Answers (1)

Guillaume
Guillaume on 18 Mar 2015
It's very basic matrix indexing:
A=[1 3 5 7 9];
B=[ 3 4 ];
C = A(B)
For N-d matrices, you may have to use sub2ind to go from coordinates to linear indices.
  1 Comment
Xia
Xia on 18 Mar 2015
Thank you Guillaume. You are right it's really basic and I learned from you. Again thanks for your time my friend!

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